Long-Term Evaluation of Kidney Biopsy Outcomes to Guide Continuous Quality Improvement

Long-Term Evaluation of Kidney Biopsy Outcomes to Guide Continuous Quality Improvement | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Long-Term Evaluation of Kidney Biopsy Outcomes to Guide Continuous Quality Improvement Niveditha Girimaji, Muayad Azzam, Mughees Choudhary, Pinal Patel, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9499410/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 10 You are reading this latest preprint version Abstract Background Kidney biopsy is essential for diagnosis and management but carries bleeding risks. Efforts to reduce bleeding may compromise tissue adequacy, highlighting the need to systematically evaluate biopsy performance. Understanding factors that influence both safety and adequacy can guide targeted quality improvement (QI) efforts. Methods We conducted a retrospective single-center study of native kidney biopsies (2014–2023) as part of a QI initiative to improve biopsy safety and adequacy. Multivariable logistic regression identified factors associated with major complications (need for angiography, embolization, or transfusion within seven days of biopsy) and biopsy adequacy (≥ 10 glomeruli for light microscopy and ≥ 1 glomerulus for indirect immunofluorescence and electron microscopy). Results A total of 796 biopsies were analyzed (56.2% female; median age 54.9 years; median BMI 28.9 kg/m²). An 18-gauge needle was used in 98% of biopsies. Major complications occurred in 10.3%, improving from 14.5% in 2014 to 2.8% in 2023 following prior QI interventions. Biopsy adequacy was achieved in 58.4%. Higher hemoglobin (adjusted odds ratio (aOR) 0.73, 95% CI 0.60–0.90) and platelet count (aOR 0.88, 95% CI 0.79-1.00) were associated with lower complications, whereas acute kidney injury (aOR 4.44 (95% CI 1.49–13.24), elevated INR (aOR 2.72 (95% CI 1.03–7.19) increased risk. Biopsy adequacy was higher with Radiologist #6 (aOR 2.59, 95% CI 1.47–4.55) and #4 (aOR 2.24, 95% CI 1.07–4.66), longer biopsy core length (aOR 2.13, 95% CI 1.53–2.98), and lower BMI (aOR 0.97, 95% CI 0.94–0.99). Conclusion This study will inform the design of multidisciplinary QI interventions to improve kidney biopsy adequacy and further reduce the complication rate. Planned interventions include peer discussions led by proceduralists with the best adequacy outcomes and a high-risk biopsy protocol. Though center-specific, these results emphasize the value of local data in improving biopsy safety and establishing benchmarks for future guidelines. Kidney Biopsy Biopsy complications Biopsy adequacy Quality improvement Figures Figure 1 Figure 2 Figure 3 Introduction Kidney biopsies are essential in diagnosing, classifying, and managing renal diseases. 1 Additionally, with advances in molecular pathology and genomics, kidney biopsy is increasingly used in research to identify biomarkers and advance personalized medicine in nephrology. 2 Despite its diagnostic utility, kidney biopsies are invasive with inherent risks, including major bleeding that may require transfusion, diagnostic angiogram, or coil embolization, formation of arteriovenous fistula, and, in rare cases, nephrectomy or death. 3 Major complications are rare and have declined over time. 3 , 4 In addition to careful consideration of procedural risk, a kidney biopsy sample must be “adequate” for accurate diagnosis. Inadequate kidney biopsy risks misclassifying disease, delaying appropriate treatment, and increasing the need for repeat biopsy, thereby increasing healthcare costs and patient burden. In contrast to the declining trend in complications, a recent review of 123,372 native kidney biopsies from years 2005 to 2020 reported rising rates in biopsy inadequacy, attributed to smaller specimen sizes, insufficient cortical tissue, and fewer glomeruli per specimen. 5 At our institution, we observed fluctuating inadequacy and occasional preventable complications suggesting that both local procedural practices and patient-specific factors may influence outcomes. This highlighted the need to closely examine our biopsy workflow to identify modifiable contributors to performance. Accordingly, this study evaluates clinical, laboratory, radiologic, and procedural factors associated with biopsy outcomes to identify actionable targets for an institution-level quality improvement (QI) initiative to simultaneously enhance overall biopsy adequacy rates and improve patient safety by minimizing complications. Methods Study design and patient selection This was a retrospective cohort study that included adults older than 18 years of age who underwent a clinically indicated native kidney biopsy from January 2014 to December 2023 at the University of Kansas Medical Center (KUMC), a tertiary referral center in Kansas. We excluded allograft and renal mass biopsies. Biopsy technique Interventional radiologists (IR) performed biopsies by real-time ultrasound (USG) or computed tomography (CT) guidance, using a spring-loaded biopsy gun. Complete blood count (CBC), international normalized ratio (INR), and basic metabolic panel (BMP) were required within the last 30 days before the biopsy. The acceptable pre-biopsy levels of hemoglobin, platelet count, and INR were ≥8.5 g/dL, ≥100×10 9 /L and ≤1.5, respectively. For elective biopsies, the hospitalist service admitted patients overnight for observation. Patients maintained 6 hours of bed rest and avoided strenuous activity for 24 hours. Hemoglobin was measured 5 hours post-biopsy, CBC and BMP the next morning. Hospitalists or nephrologists ordered post-procedure imaging if bleeding was clinically suspected. Data extraction and Definitions We reviewed electronic medical records to obtain demographic, radiologic, laboratory, histopathological, procedure-related, and clinical data. We defined pre-biopsy serum creatinine, INR, and platelet count as the most recent values obtained within 30 days, pre-biopsy hemoglobin within 7 days, and post-biopsy hemoglobin obtained 4–6 hours afterwards. We recorded estimated glomerular filtration rate (eGFR) only in patients with stable creatinine and Chronic Kidney Disease (CKD) stages 3–5. The laboratory used the Modification of Diet in Renal Disease (MDRD) equation to calculate eGFR before 2021, and the Chronic Kidney Disease Epidemiology Collaboration (2021) equation afterwards. We recorded systolic (SBP) and diastolic blood pressures (DBP) immediately pre-biopsy, and the maximum SBP and DBP within 24 hours after biopsy based on review of all vital signs. We defined post-biopsy hypotension as SBP < 100 mm Hg within 24 hours. Kidney length was based on radiology reports within one year of biopsy, and if radiologic reported size was unavailable, we manually measured length from available images. We manually measured cortical thickness from USG images within one year before or after the biopsy, with no data if images were of poor quality. The investigators obtained procedure details from IR reports and specimen details from histopathology reports. We defined “active anticoagulation” as the use of therapeutic heparin, intravenous heparin bridging (held 4–6 hours pre-biopsy) and subcutaneous low-molecular-weight- heparin (LMWH) bridging (held 24 hours pre-biopsy) for patients on warfarin (held 5 days, INR ≤ 1.5), or direct oral anticoagulants (held for 4–6 doses). We did not consider aspirin, clopidogrel, or prophylactic dosing of pharmacological anticoagulation as part of this definition. We classified biopsies as “elective” if they were preplanned. Outcomes We defined a major complication as the need for angiography, embolization, or transfusion within 7 days of biopsy. Hematoma detected on imaging within 7 days post-biopsy was a minor complication. For adequacy, we utilized 2 different definitions. We defined adequacy as a composite of ≥ 10 glomeruli in light microscopy (LM), and ≥ 1 glomerulus for indirect immunofluorescence (IF), and ≥ 1 glomerulus for electron microscopy (EM). We defined “minimal adequacy” as ≥ 10 total glomeruli (including LM and IF and EM). 6 , 7 (Table 1 ) Table 1 Definitions of Outcomes Major Complication Need for angiography, embolization, or transfusion within 7 days of biopsy Minor Complication Hematoma detected on imaging within 7 days post-biopsy Biopsy Adequacy ≥ 10 glomeruli in light microscopy (LM), and ≥ 1 glomerulus for indirect immunofluorescence (IF), and ≥ 1 glomerulus for electron microscopy (EM) Minimal Adequacy ≥ 10 total glomeruli (including LM and IF and EM) Statistical Analysis We summarized categorical variables using absolute and relative frequencies and continuous variables using the median and interquartile range. We used generalized estimating equations (GEE) with a logistic link function and an independent working correlation structure to account for potential nonindependence of observations from individuals contributing to repeat biopsies. This allowed us to estimate odds ratios of major complication, hematoma, biopsy adequacy, and minimal adequacy (each using a separate model) for covariates selected a priori based on clinical knowledge. To address missing data across all regression models, we used multiple imputation by chained equations with M = 20 imputed datasets, as implemented in the “mice” package, and pooled estimates using Rubin’s rules. We set statistical significance at α = 0.05 and conducted all analyses in R (v4.4.1). We also analyzed trends in complication and adequacy outcomes over time. Ethics and Funding This study was approved by the Institutional Review Board of University of Kansas Medical Center (IRB#STUDY00161445) and conducted in accordance with the Declaration of Helsinki; informed consent was waived due to the retrospective design. The clinical and research activities being reported are consistent with the Principles of the Declaration of Istanbul as outlined in the “Declaration of Istanbul on Organ Trafficking and Transplant Tourism”. All authors declare no conflict of interest. Results Baseline characteristics We included 796 kidney biopsies performed in 763 adult patients. Eleven biopsies in children were excluded. The median age was 54.9 (IQR 37.9–66.0) years, 447 (56.2%) were females, and the median BMI was 28.9 (IQR 24.6–34.3) kg/m 2 . Median pre-biopsy hemoglobin was 10.5 (IQR 9.1–12.6) g/dL, platelet count 231 (IQR 176.0–299.8) ×10 9 /L, and INR 1.0 (IQR 1.0–1.1). Median pre-biopsy serum creatinine was 2.0 (IQR 1.2–3.5) mg/dL. Of 796 biopsies, 95.4% were US-guided, 4.6% were CT-guided, and 432 (54.3%) were elective biopsies. Median length of the kidney was 11.0 (IQR 10.0–12) cm and median cortical thickness was 9.6 (IQR 8.1–10.8) mm. 18-gauge biopsy needles were used in 780 (97.99%) biopsies; 16-gauge biopsy needles were used in 16 (2.01%) biopsies. The median number of passes and cores was 3 each. Patients with acute kidney injury (AKI) or AKI on CKD comprised 18.9% of biopsies. In patients with CKD, eGFR (mL/min/1.73 m 2 ) ranged from ≥ 60 in 24%, 45–59 in 8.2%, 30–44 in 8.2%, 15-29 in 19.2%, and < 15 in 14.5%. The median eGFR (mL/min/1.73 m 2 ) in CKD stage ≥3 was 31.0 (IQR 19.5–43.0). Median pre-biopsy SBP was 132.0 (IQR 119.0–144.0) mm Hg and DBP was 77.0 (IQR 69.0–87.0) mm Hg. Median peak post-biopsy SBP was 146.0 (133.0–159.0) mm Hg and DBP was 85.0 (75.0–95.0) mm Hg. Fifty-two (6.4%) biopsies received active anticoagulation. Seventeen biopsies (2.1%) were repeats for inadequacy and 16 (2.01%) for other clinical indications. Baseline characteristics are described in Table 2. Table 2. Baseline demographic and clinical data. Overall, N =796 Demographics Age at biopsy (years)—median (IQR) 54.9 (37.9–66.0) Sex— n (%) Female 447 (56.2) Male 349 (43.8) Body mass index (kgm −2 )—median (IQR) 28.9 (24.6–34.3) Laboratory measures Preprocedural hemoglobin (g/dL)—median (IQR) 10.5 (9.1–12.6) Preprocedural platelet count (×10 9 /L)—median (IQR) 231.0 (176.0–299.8) Preprocedural INR—median (IQR) 1.0 (1.0–1.1) Preprocedural creatinine (mg/dL)—median (IQR) 2.0 (1.2–3.5) Preprocedural estimated glomerular filtration rate (mL/min/1.73 m 2 )— n (%) ≥60 191/795 (24.0) <60 604/795 (75.1) 45–59 65/795 (8.2) 30–44 121/795 (15.2) 15–29 153/795 (19.2) <15 115/795 (14.5) Preprocedural estimated glomerular filtration rate (mL/min/1.73 m 2 ) in CKD stage ≥3—median (IQR) 31.0 (19.5–43.0) Clinical measures Preprocedural systolic blood pressure (mm Hg)—median (IQR) 132.0 (119.0–144.0) Preprocedural diastolic blood pressure (mm Hg)—median (IQR) 77.0 (69.0–87.0) Peak postprocedural systolic blood pressure (mm Hg)—median (IQR) 146.0 (133.0–159.0) Peak postprocedural diastolic blood pressure (mm Hg)—median (IQR) 85.0 (75.0–95.0) Active Anticoagulation*— n (%) 52 (6.5) Elective biopsy— n (%) 432 (54.3) Acute kidney injury — n (%) 150/795 (18.9) Radiologic measures Length of kidney biopsied (cm)—median (IQR) 11.0 (10.0–12.0) Cortical thickness of kidney (mm)—median (IQR) 9.6 (8.1–10.8) Guidance type— n (%) Ultrasound 759 (95.4) Computed tomography 37 (4.6) Number of passes —median (IQR) 3 Needle Gauge — n (%) 18-gauge 16-gauge 780(97.99%) 16(2.01%) INR, International Normalized Ratio, *active anticoagulation: use of therapeutic heparin drip, intravenous heparin bridge and subcutaneous low molecular weight heparin (LMWH) bridge for patients previously on warfarin, or direct oral anticoagulants. Outcomes Complications: Major complications occurred in 82 biopsies (10.3%). Twenty-three (2.9%) biopsies required angiography alone, and 21 (2.6%)required embolization. Blood transfusion was required in 9.8% of biopsies: 32 (4.0%) within 24 hours and 46 (5.8%) after 24 hours. Hypotension developed in 109 (13.7%)biopsies after procedure. Median change in hemoglobin after biopsy was -0.3 (IQR -0.8–0.2) g/dL. A hemoglobin drop of >1 g/dL was observed in 109 (13.7%)biopsies and hematoma within 7 days post-biopsy was observed in 93 (11.7%) biopsies. (Table 3) Table 3: Outcomes: Complications and Adequacy Complications At least one major complication— n (%) 82/795 (10.3) Embolization— n (%) 23 (2.9) Angiography— n (%) 21 (2.6) Blood transfusion (within 24 hours)— n (%) 32/795 (4.0) Blood transfusion (within 1–7 days)— n (%) 46/795 (5.8) Clinical concern for hypotension (within 24 hours)— n (%) 109/793 (13.7) Hematoma— n (%) 93 (11.7) ≥1 g/dL drop in hemoglobin—n (%) 142/724 (19.6) Specimen adequacy Biopsy adequacy— n (%) * 441/755 (58.4) Minimal adequacy— n (%) # 669 (84.0) Number of cores —median 3 Total glomeruli count—median (IQR) 21.5 (14.0–33.0) Re-biopsy for inadequacy— n (%) 17 (2.1) Light microscopy Glomeruli count—median (IQR) 14.0 (8.0–20.0) Specimen adequacy— n (%) 1 529/786 (67.3) Immunofluorescence Glomeruli count—median (IQR) 6.0 (3.0–10.0) Specimen adequacy— n (%) 2 677/775 (87.4) Electron microscopy Glomeruli count—median (IQR) 2.0 (1.0–3.5) Specimen adequacy— n (%) 3 660/742 (88.9) *Biopsy adequacy defined as ≥ 10 glomeruli in light microscopy (LM), and ≥ 1 glomerulus for indirect immunofluorescence (IF), and ≥ 1 glomerulus for electron microscopy (EM), # Minimal adequacy defined as ≥ 10 total glomeruli (including LM and IF and EM), 1 Specimen adequacy for LM defined as ≥ 10 glomeruli, 2 Specimen adequacy for IF defined as ≥ 1 glomerulus, 3 Specimen adequacy for EM defined as ≥ 1 glomerulus Adequacy : Samples were “adequate” in 441 (58.4%) biopsies, and “minimally adequate” in 669 (84.0%) cases. Adequacy rates for LM, EM, and IF were 67.3%, 87.4%, and 88.9%, respectively. The median number of total glomeruli was 21.5 (IQR 14.0–33.0). The median number of glomeruli in LM, IF, and EM were 14.0 (IQR 8.0–20.0), 6.0 (IQR 3.0–10.0) and 2.0 (IQR 1.0–3.5), respectively. (Table 3) Figure 1 illustrates the trends in complication and adequacy rates over time. Figure 1. Trends in major complication and biopsy adequacy rates over time Figure Legend: Panel a: Major complications over time: horizontal axis describes the year of biopsy; vertical axis describes the biopsy counts; the bar graphs represent the rate and percentage of major complications, Panel b: Biopsy adequacy over time: horizontal axis describes the year of biopsy; vertical axis describes the biopsy counts; the bar graphs represent the rate and percentage of biopsy adequacy Multivariable GEE analysis of factors associated with major complications and hematoma Higher hemoglobin was associated with lower odds of major complication (adjusted OR (aOR) 0.73, 95% CI 0.60–0.90, p = 0.003 ) . Higher platelet count was associated with lower odds of both major complications (aOR 0.88, 95% CI 0.79–1.00, p = 0.045) and hematoma (aOR 0.86, 95% CI 0.76–0.99, p = 0.031). AKI (aOR 4.44 (95% CI 1.49–13.24), p = 0.007) and higher INR (aOR 2.72, 95% CI 1.03–7.19, p=0.043) had higher odds of major complications. CKD stage 5 had an aOR of 3.09, 95% CI 0.98–9.69, p=0.053). Higher cortical thickness had higher odds of major complications (aOR 1.22, 95% CI 1.03–1.44, p=0.019). Biopsies by Radiologist #2 were associated with higher odds of hematoma (aOR 3.12, 95% CI 1.06–9.16, p=0.038). Age, sex, BMI, USG versus CT guidance, 16g versus 18g, number of passes, preprocedural SBP and DBP, length of the kidney, elective versus emergency biopsy, and active anticoagulation were not associated with major complications or hematoma. (Table 4, Figure 2) Table 4. Multivariable GEE analysis of factors associated with major complications and hematoma Major complication Hematoma aOR (95% CI) p- value aOR (95% CI) p- value Age at biopsy (years) 1.01 (0.99–1.03) 0.47 1.00 (0.99–1.02) 0.93 Male vs Female 1.39 (0.78–2.47) 0.26 0.87 (0.52–1.43) 0.57 Body mass index (kg/m 2 ) 0.99 (0.95–1.03) 0.50 0.99 (0.95–1.02) 0.38 Preprocedural hemoglobin (g/dL) 0.73 (0.60–0.90) 0.003 0.98 (0.85–1.13) 0.75 Preprocedural platelet count (×10 9 /L) 1 0.88 (0.79–1.00) 0.045 0.86 (0.76–0.99) 0.031 Preprocedural INR 2.72 (1.03–7.19) 0.043 1.37 (0.43–4.31) 0.59 Radiologist 2 #2 vs #1 1.80 (0.54–5.99) 0.34 3.12 (1.06–9.16) 0.038 Guidance type Computed tomography vs Ultrasound 1.76 (0.64–4.87) 0.28 1.38 (0.51–3.74) 0.53 Number of passes 0.99 (0.75–1.31) 0.95 1.05 (0.80–1.38) 0.72 Maximum core length (cm) 1.24 (0.86–1.81) 0.25 1.14 (0.80–1.62) 0.46 Needle gauge 18 vs 16 0.50 (0.10–2.50) 0.40 0.29 (0.07–1.14) 0.077 Length of kidney biopsied (cm) 0.90 (0.74–1.08) 0.24 1.02 (0.87–1.20) 0.80 Cortical thickness of kidney (mm) 1.22 (1.03–1.44) 0.019 1.05 (0.92–1.19) 0.47 Es0timated glomerular filtration rate (mL/min/1.73 m 2 ) 45–59 vs ≥60 1.61 (0.33–7.95) 0.56 1.11 (0.39–3.15) 0.85 30–44 vs ≥60 1.43 (0.37–5.50) 0.60 1.59 (0.65–3.88) 0.31 15–29 vs ≥60 1.86 (0.60–5.77) 0.28 1.43 (0.65–3.17) 0.37 <15 vs ≥60 3.09 (0.98–9.69) 0.053 1.67 (0.67–4.18) 0.27 Acute kidney injury 4.44 (1.49–13.24) 0.007 1.51 (0.65–3.53) 0.34 Elective biopsy 0.65 (0.34–1.25) 0.19 0.82 (0.45–1.49) 0.51 Preprocedural systolic blood pressure (mm Hg) 1.00 (0.98–1.02) 0.89 1.00 (0.99–1.02) 0.90 Preprocedural diastolic blood pressure (mm Hg) 1.02 (1.00–1.04) 0.11 1.02 (1.00–1.04) 0.10 Active anticoagulation 3 1.15 (0.43–3.08) 0.78 1.60 (0.71–3.59) 0.26 GEE, generalized estimating equations; Major complications, need for angiography, embolization, or transfusion within seven days of biopsy; aOR, adjusted Odds Ratio; INR, International Normalized Ratio; 1 Platelet count was rescaled so that each unit represents a change of 50×10 9 /L for interpretation of odds ratio, 2 Radiologist #1 used as reference, For major complications: radiologists #3–#9 had aORs 0.91–3.95 (all p > 0.05)., For hematoma: only Radiologist #2 showed a significant association; others not significant., Radiologist #8 was excluded due to insufficient sample size (n=1), 3 active anticoagulation: use of therapeutic heparin drip, intravenous heparin bridge and subcutaneous low molecular weight heparin (LMWH) bridge for patients previously on warfarin, or direct oral anticoagulants. Figure 2: Forest plot of factors associated with major complications Figure Legend: Forest plot displays the adjusted odds ratios (aORs) and 95% confidence intervals for variables included in the multivariable generalized estimating equations (GEE) analysis evaluating major biopsy complications. The vertical dashed line represents the null value (aOR = 1). Point estimates are shown with black circles and horizontal 95% confidence-interval bars; variables with statistically significant associations (p < 0.05) have blue labels. CT, Computed Tomography; USG, Ultrasound; eGFR, estimated glomerular filtration rate; SBP, systolic blood pressure; DBP, diastolic blood pressure; *Radiologist #1 used as reference, radiologists #2, #3, #4, #5, #6, #7, and #9 had aORs 0.98–1.75 (all p > 0.05), Radiologist 8 was excluded due to insufficient sample size (n=1); # active anticoagulation: use of therapeutic heparin drip, intravenous heparin bridge and subcutaneous low molecular weight heparin (LMWH) bridge for patients previously on warfarin, or direct oral anticoagulants. Sensitivity analysis for major complications using dichotomous pre-biopsy hemoglobin, excluding biopsies with INR>1.5 and/or platelet count <100×10 9 /L Hemoglobin <10 g/dL (aOR 2.4, 95% CI 1.17-5.06, p = 0.017) and AKI (aOR 3.73, 95% CI 1.20-11.56, p=0.023) was associated with major complications. Cortical thickness, platelet count, and INR showed no association to major complications. (Table S1) Multivariable GEE analysis of factors associated with biopsy adequacy Biopsies performed by Radiologist #6 (aOR 2.13, 95% CI 1.53–2.98, p<0.001) and longer maximum core length (aOR 2.59, 95% CI 1.47–4.55, p<0.001) were associated with greater biopsy adequacy. Higher BMI was associated with lower biopsy adequacy (aOR 0.97, 95% CI 0.94–0.99, p = 0.003). Biopsies performed by Radiologist #4 (aOR 2.24, 95% CI 1.07–4.66, p=0.031) and #6 (aOR 6.09, 95% CI 2.74–13.53, p=<0.001) were associated with greater “minimal adequacy”. Age, sex, USG versus CT guidance, 16g versus 18g, number of passes, cortical thickness, kidney length, elective versus emergency biopsy, AKI, and CKD stages were not associated with biopsy adequacy or minimal adequacy. (Table 5, Figure 3) Table 5. Multivariable GEE analysis of factors associated with biopsy adequacy Biopsy adequacy Minimal adequacy aOR (95% CI) p- value aOR (95% CI) p- value Age at biopsy (years) 0.99 (0.98–1.00) 0.10 0.99 (0.98–1.00) 0.21 Male 0.79 (0.57–1.09) 0.15 0.79 (0.53–1.19) 0.26 Body mass index (kg/m 2 ) 0.97 (0.94–0.99) 0.003 0.98 (0.95–1.01) 0.22 Radiologist 1 #4 vs #1 1.15 (0.63–2.08) 0.65 2.24 (1.07–4.66) 0.031 #6 vs #1 2.59 (1.47–4.55) <0.001 6.09 (2.74–13.53) <0.001 Guidance type Computed tomography vs Ultrasound 0.83 (0.41–1.68) 0.60 0.44 (0.19–1.02) 0.056 Number of passes 1.21 (0.95–1.55) 0.12 0.94 (0.72–1.21) 0.61 Maximum core length (cm) 2.13 (1.53–2.98) <0.001 1.84 (1.16–2.91) 0.009 Needle gauge 18 vs 16 1.72 (0.44–6.66) 0.43 2.53 (0.77–8.26) 0.12 Length of kidney biopsied (cm) 1.08 (0.96–1.21) 0.22 0.94 (0.81–1.10) 0.45 Cortical thickness of kidney (mm) 0.96 (0.87–1.07) 0.47 0.93 (0.81–1.08) 0.35 Estimated glomerular filtration rate (mL/min/1.73 m 2 ) 45–59 vs ≥60 0.78 (0.41–1.48) 0.44 1.26 (0.51–3.10) 0.62 30–44 vs ≥60 0.86 (0.50–1.47) 0.57 0.87 (0.44–1.71) 0.69 15–29 vs ≥60 0.90 (0.55–1.47) 0.67 0.96 (0.49–1.86) 0.90 <15 vs ≥60 0.84 (0.48–1.47) 0.53 0.69 (0.34–1.39) 0.30 Acute kidney injury 1.12 (0.66–1.89) 0.68 1.13 (0.56–2.29) 0.74 Elective biopsy 1.35 (0.95–1.93) 0.10 0.92 (0.58–1.45) 0.71 GEE, generalized estimating equations; INR, International Normalized Ratio; ¹Radiologist #1 used as reference, For biopsy adequacy: radiologists #2, #3, #5, #7, and #9 had aORs 0.98–1.75 (all p > 0.05), For minimal adequacy: radiologists #2, #3, #5, #7, and #9 had aORs 1.02–1.61 (all p > 0.05), Only radiologists #4 and #6 were significantly associated with biopsy adequacy outcomes, Radiologist #8 was excluded due to insufficient sample size (n=1) Figure 3: Forest plot of factors associated with biopsy adequacy Figure Legend: Forest plot displays the adjusted odds ratios (aORs) and 95% confidence intervals for variables included in the multivariable generalized estimating equations (GEE) analysis evaluating biopsy adequacy. The vertical dashed line represents the null value (aOR = 1). Point estimates are shown with black circles and horizontal 95% confidence-interval bars; variables with statistically significant associations (p < 0.05) have blue labels. CT, Computed Tomography; USG, Ultrasound; eGFR, estimated glomerular filtration rate; SBP, systolic blood pressure; DBP, diastolic blood pressure; *Radiologist #1 used as reference, radiologists #2, #3, #4, #5, #7, and #9 had aORs 0.98–1.75 (all p > 0.05), Radiologist 8 was excluded due to insufficient sample size (n=1) # active anticoagulation: use of therapeutic heparin drip, intravenous heparin bridge and subcutaneous low molecular weight heparin (LMWH) bridge for patients previously on warfarin, or direct oral anticoagulants. Discussion In this large single-center retrospective study of nearly 800 native kidney biopsies for over a decade, we observed an overall major complication rate of 10.3%, primarily associated with lower pre-biopsy hemoglobin and platelet count, elevated INR, and presence of AKI and CKD 5. Only 58.4% of biopsies were adequate, with a striking association between proceduralist identity and adequacy, in addition to longer biopsy cores, and lower BMI. Major complication rates declined over time, likely reflecting the impact of prior QI efforts, whereas biopsy adequacy remained largely unchanged. The major complication and the individual angiography and embolization rates in this cohort were higher than those reported in previous studies 3,4 . Two meta-analyses of native kidney biopsies studies conducted worldwide report blood transfusion rates of 0.9%-1.6%, embolization of 0.3%, and angiography of 0.62%. 3,4 Major complication rate in our study however, declined over the years from 14.5% in 2014 to 2.8% in 2023, approaching the complication rate described in literature. The hematoma rate in biopsies that had post-biopsy imaging was 11.9%, similar to the rate reported in a meta-analysis. 3 This likely reflects our selective imaging approach, in contrast to studies using routine ultrasound—which detect substantially more, often clinically insignificant, hematomas. 9,10 This study found that hemoglobin >10 g/dL was associated with lower odds of major complications. Anemia worsens bleeding due to functional platelet dysfunction and decreased margination with increased laminar platelet flow when hematocrit is low. 11,12 Additionally, anemia may reflect an inflammatory systemic disease or advanced kidney disease, potentially serving as a proxy for other risk factors for bleeding, including uremic platelet dysfunction. Higher hemoglobin also decreases the clinical trigger to transfuse in response to post-biopsy hemoglobin drop. A meta-analysis found that pre-biopsy hemoglobin of ≥12 g/dL was associated with a lower blood transfusion rate (0.5% vs 2.6%, p=0.001). 4 Higher platelet count was protective against complications in our study, consistent with previous studies. 8,13,14 . Elevated INR was also associated with 2.84-fold higher odds of major complications. Complications were especially higher among biopsies with a platelet count 1.5 (23.8%). In the sensitivity analysis that excluded biopsies with platelet count of 1.5, INR and platelet count were not associated with complications, reiterating the safety of these cut-offs. AKI was associated with major biopsy complications in our cohort, and this association is well known. 3,4,8,14–16 In a study of hospitalized acute kidney disease patients undergoing kidney biopsy, 8% required blood transfusion, and 2% required intervention, which is higher than general complication rate. 17 AKI patients are more likely to be critically ill with other systemic illnesses, which may explain the higher risk of bleeding complications. CKD stage 5 had increased odds of major complication in our cohort, although not reaching significance. In a study of kidney biopsy in patients with an eGFR <15 ml/min/m 2 , 28% had complications, including blood transfusion and intervention. 18 This higher bleeding complication can be explained by the acquired platelet dysfunction seen in advanced uremia. 19 Higher blood pressure was not associated with complications in our study. Hypertension, when defined as SBP higher than 160 mm Hg, has been associated with complications, although a meta-analysis failed to show an increased risk with SBP >130 mm Hg. 4,15,20,21 Median blood pressure in our study was well controlled and within protocol threshold (<150/90 mm Hg), reflecting real-world practice. Notably, inpatient blood pressure does not consistently represent true blood pressure and is subject to several confounding physiological and hospital environmental factors. 22 Hematoma was significantly more with biopsies by Radiologist #2, although not associated with major complications. Age, sex, and BMI were not associated with complications unlike some other studies that have shown an association of female sex and advanced age with complications. 8,16,23 , 14 Higher cortical thickness was associated with major complications, which was unexpected; however, the clinical significance of this finding is limited due to measurement error from manually assessing limited or poor-quality USG images. This is also demonstrated by the fact that cortical thickness was not associated with major complications in sensitivity analysis. Biopsy needle gauge (16-gauge vs 18-gauge) was not associated with complications; however, this comparison is not reliable due to the small number of biopsies performed with 16-gauge (2%). Prior studies demonstrate comparable complication risks between the two needle sizes. 24–26 KDIGO and Banff recommend 8–10 glomeruli ≥10 glomeruli with 2 arteries for native and transplant biopsies, respectively. 6,7 However, these guidelines do not specify whether the thresholds apply only to LM or also to IF/EM. We defined adequacy by requiring sufficient glomeruli on LM, along with minimum glomerular counts on IF and EM to ensure each modality could be meaningfully interpreted and contribute to diagnostically adequate tissue across the spectrum of kidney diseases. Only 58.4% of biopsies in this cohort were “adequate,” and 84% were “minimally adequate,” per our defined methods. A retrospective study of 123,372 native kidney biopsies analyzed at Arkana Laboratories from 2005 to 2020 reported an increasing rate of inadequate biopsy samples, rising from 2% in 2005 to 14% in 2020. 5 The adequacy rates in our study remained predominantly similar from 2016 to 2023, with a maximum adequacy of 65.5% achieved in 2020. Longer biopsy core, reflecting greater biopsy depth, was associated with higher adequacy suggesting shallower biopsies contributed to inadequate samples. Higher total core length has been shown to result in a higher glomerular yield. 27 Very deep biopsies, however, predominantly sample the medulla, missing the cortex, whereas superficial biopsies sample the cortex incompletely. The optimal biopsy starts at the outer cortex and has adequate depth in order to obtain sufficient glomeruli, while avoiding complications. Deep medullary biopsies cause more bleeding due to the presence of larger vessels. 27,28 The relationship of biopsy depth and adequacy also depends on biopsy angle, as tangential approach has better adequacy and lower complications compared to perpendicular approach. 29 Calculating optimal depth of biopsy using patient body weight and height improved outcomes in one study. 30 Proceduralist identity significantly influenced adequacy. Radiologist #6 had the highest odds of adequate biopsy, and #4 and #6 had higher odds of obtaining a minimally adequate biopsy. This finding is novel, and it underscores the critical role of the individual proceduralist, as several factors are operator-dependent and unique to individual techniques and experience. While biopsies were traditionally performed by nephrologists and in recent years are more often performed by radiologists, this appears less important than individual proceduralist experience. Some studies have shown nephrologists to have fewer miss rates compared to radiologists, while others have shown similar adequacy rates. 5,31–33 Higher BMI was associated with lower adequacy, consistent with a study that showed lower glomeruli count in obese compared to non-obese patient biopsies. 34 We could not assess the association of needle gauge with adequacy, as very few biopsies were performed with 16-gauge. 16-guage needles provide higher glomeruli count than 18-gauge with greater percentage of adequate biopsy samples. 25 18-guage needle has a diameter of 350 μm, only slightly larger than the average glomerular diameter (250 μm), whereas the 16-gauge needle measures 700 μm, supporting its use for improved glomerular yield. 35 As the gauge size increased from 14 G to 20 G, Nissen et al. observed a decline in glomerular count from 25 ± 0.9/cm to 2 ± 1.0/cm (mean ± SEM). 5 The overarching aim of this study is to implement QI initiatives. Although complication rates improved, this was not paralleled by gains in adequacy rates, possibly due to proceduralists performing shallower biopsies with an 18-gauge needle to minimize complications. Our goal, as part of ongoing QI, will be to optimize adequacy rates to 90% while continuing to minimize complications: we feel the most impactful intervention is targeted training by radiologists with highest adequacy rates that involves learning from their procedural nuances including angle and depth of biopsy. Utilizing real-time bedside scanning microscope to confirm adequate glomerular sampling can be useful. 31,36 Similarly, assessment of biopsies using web-based tools to analyze photographs taken with smartphones and utilizing machine learning algorithms to analyze the cortical percentage can improve adequacy. 37–39 Switching to 16-gauge will best balance complications and adequacy. Complications can be further minimized by implementing a specific protocol for patients at higher risk (AKI, CKD 5), including a stricter pre-biopsy hemoglobin of ³10 g/dL, avoiding biopsies in patients with INR>1.5 and platelet count <100×10 9 /L, and performing eligible tests closer to elective biopsy. Pre-biopsy use of desmopressin 0.3-0.4 mcg/kg in the minutes just prior to biopsy was used in selected patients, based on theoretical and limited clinical evidence of reduced bleeding in advanced CKD. 40,41 The next phase in our QI project will analyze the benefits of desmopressin in a larger patient cohort. The strength of this study is the large sample size and extensive analysis of variables that can affect both biopsy complications and adequacy. Importantly, our findings provide real, center-specific data to guide future QI efforts. The limitations are the inherent flaws of a retrospective study and limited applicability due to single-center design. Kidney length and cortical thickness were manually measured, and subject to interobserver variability and possible inaccuracies due to poor imaging quality. We did not measure the angle of biopsy, and assessing the angle based on available images is challenging, if not impossible. Lastly, although there was missing data, we managed this by multiple imputation methods. In conclusion, in this study of native kidney biopsies over a decade, the overall major complication rate declined with earlier QI initiatives. Biopsy adequacy, however, remained suboptimal, with an inadequacy rate of 40% and no significant improvement over time — emphasizing the need for continued, targeted efforts to optimize adequacy. Based on our finding of higher risk of complications in patients with AKI, CKD stage 5 and low hemoglobin, we plan to implement measures to further improve safety in this high-risk group. Peer-training by specific proceduralists—a key determinant of adequacy—will guide future QI efforts for adequacy. Declarations Ethics approval and consent to participate Study approval statement: This study was approved by the Institutional Review Board of University of Kansas Medical Center (IRB#STUDY00161445) and conducted in accordance with the Declaration of Helsinki Consent to participate statement: Informed consent was waived by the IRB of University of Kansas Medical Center (IRB#STUDY00161445) due to the retrospective design Consent for publication: Not applicable Availability of data and materials: The data that support the findings of this study are openly available in “figshare” at https://doi.org/10.6084/m9.figshare.31222999 Competing interests : The authors declare that they have no competing interests Conflict of Interest Statement: The authors have no conflicts of interest to declare Funding: This study was not supported by any sponsor or funder Authors' contributions NG: Led data extraction, supervised the project, managed project administration, and wrote the original draft of the manuscript. MA: Performed statistical analyses, provided methodological support, prepared figures, and critically reviewed the manuscript. MC: Contributed to data extraction and reviewed the manuscript. PP: Contributed to data extraction and reviewed the manuscript. CS: Contributed to data extraction and reviewed the manuscript. MZ: Contributed to data extraction and reviewed the manuscript. GG: Contributed to data extraction and reviewed the manuscript. JA: Provided statistical expertise and analysis, prepared figures, and reviewed the manuscript. DJ: Conceived and conceptualized the project, provided oversight and methodological support, and critically revised the manuscript. RM: Conceived and oversaw the project, designed the study, managed project administration, provided methodological support, and critically revised the manuscript. Acknowledgements : The authors declare that they have no competing interests References Dhaun N, Bellamy CO, Cattran DC, Kluth DC. Utility of renal biopsy in the clinical management of renal disease. Kidney Int. 2014;85(5):1039–48. 10.1038/ki.2013.512 . de Boer IH, Alpers CE, Azeloglu EU, et al. Rationale and design of the Kidney Precision Medicine Project. Kidney Int. 2021;99(3):498–510. 10.1016/j.kint.2020.08.039 . Poggio ED, McClelland RL, Blank KN, et al. Systematic Review and Meta-Analysis of Native Kidney Biopsy Complications. Clin J Am Soc Nephrol. 2020;15(11):1595. 10.2215/CJN.04710420 . Corapi KM, Chen JLT, Balk EM, Gordon CE. Bleeding complications of native kidney biopsy: a systematic review and meta-analysis. Am J Kidney Dis. 2012;60(1):62–73. 10.1053/j.ajkd.2012.02.330 . Nissen CJ, Moreno V, Davis VG, Walker PD. Increasing Incidence of Inadequate Kidney Biopsy Samples Over Time: A 16-Year Retrospective Analysis From a Large National Renal Biopsy Laboratory. Kidney Int Rep. 2022;7(2):251–8. 10.1016/j.ekir.2021.11.026 . Kidney Disease: Improving Global Outcomes (KDIGO) Glomerular Diseases Work Group. KDIGO 2021 Clinical Practice Guideline for the Management of Glomerular Diseases. Kidney Int. 2021;100(4S):S1–276. 10.1016/j.kint.2021.05.021 . Roufosse C, Naesens M, Haas M, et al. The Banff 2022 Kidney Meeting Work Plan: Data-driven refinement of the Banff Classification for renal allografts. Am J Transpl. 2024;24(3):350–61. 10.1016/j.ajt.2023.10.031 . Monahan H, Gunderson T, Greene E, Schmit G, Atwell T, Schmitz J. Risk factors associated with significant bleeding events after ultrasound-guided percutaneous native renal biopsies: a review of 2204 cases. Abdom Radiol. 2019;44(6):2316–22. 10.1007/s00261-019-01962-z . Palsson R, Short SAP, Kibbelaar ZA, et al. Bleeding Complications After Percutaneous Native Kidney Biopsy: Results From the Boston Kidney Biopsy Cohort. Kidney Int Rep. 2020;5(4):511–8. 10.1016/j.ekir.2020.01.012 . Xu S, Xiong B, Lin S, Li Q, Wang L, Zhao W. Predictors of perirenal haematoma post-percutaneous ultrasound-guided renal biopsy. J Int Med Res. 2021;49(11):03000605211058377. 10.1177/03000605211058377 . Valles J, Santos MT, Aznar J, et al. Erythrocytes metabolically enhance collagen-induced platelet responsiveness via increased thromboxane production, adenosine diphosphate release, and recruitment. Blood. 1991;78(1):154–62. Turitto VT, Weiss HJ. Red blood cells: their dual role in thrombus formation. Science. 1980;207(4430):541–3. 10.1126/science.7352265 . Kajawo S, Ekrikpo U, Moloi MW, et al. A Systematic Review of Complications Associated With Percutaneous Native Kidney Biopsies in Adults in Low- and Middle-Income Countries. Kidney Int Rep. 2021;6(1):78–90. 10.1016/j.ekir.2020.10.019 . Xu Dmin, Chen M, de Zhou F, Zhao Mhui. Risk Factors for Severe Bleeding Complications in Percutaneous Renal Biopsy. Am J Med Sci. 2017;353(3):230–5. 10.1016/j.amjms.2016.12.019 . Korbet SM, Volpini KC, Whittier WL. Percutaneous Renal Biopsy of Native Kidneys: A Single-Center Experience of 1,055 Biopsies. Am J Nephrol. 2014;39(2):153–62. 10.1159/000358334 . Palsson R, Short SAP, Kibbelaar ZA, et al. Bleeding Complications After Percutaneous Native Kidney Biopsy: Results From the Boston Kidney Biopsy Cohort. Kidney Int Rep. 2020;5(4):511–8. 10.1016/j.ekir.2020.01.012 . Moledina DG, Luciano RL, Kukova L, et al. Kidney Biopsy–Related Complications in Hospitalized Patients with Acute Kidney Disease. Clin J Am Soc Nephrol. 2018;13(11):1633–40. 10.2215/CJN.04910418 . Alkadi MM, Abuhelaiqa EA, Thappy SB, et al. Kidney Biopsy in Patients With Markedly Reduced Kidney Function. Kidney Int Rep. 2022;7(11):2505–8. 10.1016/j.ekir.2022.08.004 . Sohal AS, Gangji AS, Crowther MA, Treleaven D. Uremic bleeding: Pathophysiology and clinical risk factors. Thromb Res. 2006;118(3):417–22. 10.1016/j.thromres.2005.03.032 . Shidham GB, Siddiqi N, Beres JA, et al. Clinical risk factors associated with bleeding after native kidney biopsy. Nephrology. 2005;10(3):305–10. 10.1111/j.1440-1797.2005.00394.x . Kriegshauser JS, Patel MD, Young SW, Chen F, Eversman WG, Chang YHH. Risk of Bleeding after Native Renal Biopsy as a Function of Preprocedural Systolic and Diastolic Blood Pressure. J Vasc Interv Radiol. 2015;26(2):206–12. 10.1016/j.jvir.2014.10.020 . Bress AP, Anderson TS, Flack JM, et al. The Management of Elevated Blood Pressure in the Acute Care Setting: A Scientific Statement From the American Heart Association. Hypertension. 2024;81(8):e94–106. 10.1161/HYP.0000000000000238 . Anpalahan A, Malacova E, Hegerty K et al. Bleeding Complications of Percutaneous Kidney Biopsy: Does Gender Matter? Kidney360 . 2021;2(8):1308–1312. 10.34067/KID.0002432021 Mai J, Yong J, Dixson H, et al. Is bigger better? A retrospective analysis of native renal biopsies with 16 Gauge versus 18 Gauge automatic needles. Nephrology. 2013;18(7):525–30. 10.1111/nep.12093 . Xie W, Xu J, Xie Y, et al. Adequacy and complication rates of percutaneous renal biopsy with 18- vs. 16-gauge needles in native kidneys in Chinese individuals. BMC Nephrol. 2020;21(1):337. 10.1186/s12882-020-01987-3 . Roth R, Parikh S, Makey D, et al. When Size Matters: Diagnostic Value of Kidney Biopsy according to the Gauge of the Biopsy Needle. Am J Nephrol. 2013;37(3):249–54. 10.1159/000347219 . Torigoe K, Sakamoto R, Abe S, Muta K, Mukae H, Nishino T. Factors Associated with Glomerular Yield in Percutaneous Kidney Biopsy. J Clin Med. 2023;12(12):3877. 10.3390/jcm12123877 . Beckingham IJ, Nicholson ML, Bell PR. Analysis of factors associated with complications following renal transplant needle core biopsy. Br J Urol. 1994;73(1):13–5. 10.1111/j.1464-410x.1994.tb07449.x . Sawicka K, Hassan N, Dumaine C, et al. Direction of the Biopsy Needle in Ultrasound-Guided Renal Biopsy Impacts Specimen Adequacy and Risk of Bleeding. Can Assoc Radiol J. 2019;70(4):361–6. 10.1016/j.carj.2018.11.006 . Pasquariello A, Innocenti M, Batini V, et al. Theoretical calculation of optimal depth in the percutaneous native kidney biopsy to drastically reduce bleeding complications and sample inadequacy for histopathological diagnosis. Nephrol Dial Transpl. 2007;22(12):3516–20. 10.1093/ndt/gfm272 . Ferrer G, Andeen NK, Lockridge J, et al. Kidney biopsy adequacy: A metric-based study. Am J Surg Pathol. 2019;43(1):84–92. 10.1097/PAS.0000000000001102 . Emelianova D, Prikis M, Morris CS, et al. The evolution of performing a kidney biopsy: a single center experience comparing native and transplant kidney biopsies performed by interventional radiologists and nephrologists. BMC Nephrol. 2022;23(1):226. 10.1186/s12882-022-02860-1 . Pettit C, Kanagaratnam R, Coughlan F, Graf N, Hahn D, Durkan A. Kidney biopsy adequacy and complications in children — does technique matter? Eur J Pediatr. 2022;181(7):2677–84. 10.1007/s00431-022-04464-1 . Qian L, Menez S, Hu D, et al. Safety and Adequacy of Kidney Biopsy Procedure in Patients with Obesity. Kidney360. 2023;4(1):98. 10.34067/KID.0006602022 . Luciano RL, Moeckel GW. Update on the Native Kidney Biopsy: Core Curriculum 2019. Am J Kidney Dis. 2019;73(3):404–15. 10.1053/j.ajkd.2018.10.011 . Wooldridge JT, Davis A, Fischer WG, Khalil MF, Zhang M, Afrouzian M. The Impact of Renal Tissue Procurement at Bedside on Specimen Adequacy and Best Practices. Am J Clin Pathol. 2019;151(2):205–8. 10.1093/ajcp/aqy120 . Ahangaran M, Sun E, Le K, et al. Pilot Study of a Web-Based Tool for Real-Time Adequacy Assessment of Kidney Biopsies. Kidney Int Rep. 2024;9(9):2809–13. 10.1016/j.ekir.2024.06.019 . Eigbire-Molen OJ, Cassol CA, Kenan DJ, et al. Smartphone-based machine learning model for real-time assessment of medical kidney biopsy. J Pathol Inf. 2024;15:100385. 10.1016/j.jpi.2024.100385 . Singh G, Massak M, Czaplicki M, et al. Use of a Smartphone Camera at the Bedside to Assess Adequacy of Kidney Biopsies. J Am Soc Nephrol. 2021;32(12):3024–6. 10.1681/ASN.2021070898 . Leclerc S, Nadeau-Fredette AC, Elftouh N, Lafrance JP, Pichette V, Laurin LP. Use of Desmopressin Prior to Kidney Biopsy in Patients With High Bleeding Risk. Kidney Int Rep. 2020;5(8):1180–7. 10.1016/j.ekir.2020.05.006 . Athavale A, Kulkarni H, Arslan CD, Hart P. Desmopressin and bleeding risk after percutaneous kidney biopsy. BMC Nephrol. 2019;20:413. 10.1186/s12882-019-1595-4 . Additional Declarations No competing interests reported. Supplementary Files Supplementarytable.docx Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 22 May, 2026 Reviews received at journal 19 May, 2026 Reviewers agreed at journal 12 May, 2026 Reviewers agreed at journal 10 May, 2026 Reviewers agreed at journal 07 May, 2026 Reviewers invited by journal 07 May, 2026 Editor invited by journal 25 Apr, 2026 Editor assigned by journal 24 Apr, 2026 Submission checks completed at journal 24 Apr, 2026 First submitted to journal 22 Apr, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9499410","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":641498371,"identity":"9ff812d0-d661-451a-9fb7-367382816254","order_by":0,"name":"Niveditha Girimaji","email":"","orcid":"","institution":"University of Kansas Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Niveditha","middleName":"","lastName":"Girimaji","suffix":""},{"id":641498373,"identity":"d1164789-490c-4a40-8d53-3d37d9799987","order_by":1,"name":"Muayad Azzam","email":"","orcid":"","institution":"University of Kansas Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Muayad","middleName":"","lastName":"Azzam","suffix":""},{"id":641498379,"identity":"0d2669bf-da8d-42b6-93c3-46d8e2b9446d","order_by":2,"name":"Mughees Choudhary","email":"","orcid":"","institution":"University of Kansas School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Mughees","middleName":"","lastName":"Choudhary","suffix":""},{"id":641498380,"identity":"3be7874d-ff90-42cd-afff-b251e01d2de0","order_by":3,"name":"Pinal Patel","email":"","orcid":"","institution":"University of Kansas Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Pinal","middleName":"","lastName":"Patel","suffix":""},{"id":641498381,"identity":"bebadead-ceed-4998-8f3b-ff0885829617","order_by":4,"name":"Chelsea Smith","email":"","orcid":"","institution":"University of Kansas Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Chelsea","middleName":"","lastName":"Smith","suffix":""},{"id":641498386,"identity":"94372eda-f41e-4345-aab8-92cdf5151364","order_by":5,"name":"Mallak Zatreh","email":"","orcid":"","institution":"University of Kansas Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Mallak","middleName":"","lastName":"Zatreh","suffix":""},{"id":641498392,"identity":"aeae4366-c22e-499f-b94b-d79f06a9a372","order_by":6,"name":"Gina Gabrielli","email":"","orcid":"","institution":"University of Kansas Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Gina","middleName":"","lastName":"Gabrielli","suffix":""},{"id":641498394,"identity":"fa7b4c92-2230-45dd-beae-f0edb2b19bcc","order_by":7,"name":"Justin Amarin","email":"","orcid":"","institution":"Vanderbilt University Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Justin","middleName":"","lastName":"Amarin","suffix":""},{"id":641498395,"identity":"99ebb2c3-7345-49b8-a4ff-2fa86e43ceb7","order_by":8,"name":"Duncan Johnstone","email":"","orcid":"","institution":"University of Kansas Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Duncan","middleName":"","lastName":"Johnstone","suffix":""},{"id":641498396,"identity":"2bbe3f0b-cb4d-4b5a-bc93-3903e3979d5d","order_by":9,"name":"Reem Mustafa","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAvElEQVRIiWNgGAWjYPACOQZ+HgiLsYEoDQcYjBkke0jWYnCGWC3m084Yf/5QYyBvfOaM6YYfDDayGw4Q0CJzO8dM4sAxA8NtZ3vMbvYwpBkT1CIhnWPGcIDtD+O28zxmtxkYDicSo8X4w4F/Bvab+8Fa/hOlxUDiYJtB4gbeHpCWA8RoSSuTONtnkDzjzLGymz0GycYzCWtJ3vyh4puBbX9P8rYbPyrsZPsIaUEDBqQpHwWjYBSMglGAAwAAr0FEsqsoDtkAAAAASUVORK5CYII=","orcid":"","institution":"University of Kansas Medical Center","correspondingAuthor":true,"prefix":"","firstName":"Reem","middleName":"","lastName":"Mustafa","suffix":""}],"badges":[],"createdAt":"2026-04-22 17:54:13","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9499410/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9499410/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":109493014,"identity":"b7666be4-e21b-4f23-a6ab-6a5b80d0fa12","added_by":"auto","created_at":"2026-05-18 18:29:36","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":58010,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eTrends in major complication and biopsy adequacy rates over time\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure Legend: \u003c/strong\u003ePanel a:\u003cstrong\u003e \u003c/strong\u003eMajor complications over time: horizontal axis describes the year of biopsy; vertical axis describes the biopsy counts; the bar graphs represent the rate and percentage of major complications, Panel b: Biopsy adequacy over time: horizontal axis describes the year of biopsy; vertical axis describes the biopsy counts; the bar graphs represent the rate and percentage of biopsy adequacy\u003c/p\u003e","description":"","filename":"Onlinefloatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-9499410/v1/09fb5de2a43ceed648aaff9f.png"},{"id":109760640,"identity":"06f369af-2384-428d-9c8e-45e70a2f9cc5","added_by":"auto","created_at":"2026-05-22 07:28:56","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":73501,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eForest plot of factors associated with major complications\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure Legend:\u003c/strong\u003e Forest plot displays the adjusted odds ratios (aORs) and 95% confidence intervals for variables included in the multivariable generalized estimating equations (GEE) analysis evaluating major biopsy complications. The vertical dashed line represents the null value (aOR = 1). Point estimates are shown with black circles and horizontal 95% confidence-interval bars; variables with statistically significant associations (p \u0026lt; 0.05) have blue labels. CT, Computed Tomography; USG, Ultrasound; eGFR, estimated glomerular filtration rate; SBP, systolic blood pressure; DBP, diastolic blood pressure; *Radiologist #1 used as reference, radiologists #2, #3, #4, #5, #6, #7, and #9 had aORs 0.98–1.75 (all p \u0026gt; 0.05), Radiologist 8 was excluded due to insufficient sample size (n=1); \u003csup\u003e#\u003c/sup\u003eactive anticoagulation: use of therapeutic heparin drip, intravenous heparin bridge and subcutaneous low molecular weight heparin (LMWH) bridge for patients previously on warfarin, or direct oral anticoagulants.\u003c/p\u003e","description":"","filename":"Onlinefloatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-9499410/v1/be401574bbb3909bada3d740.png"},{"id":109759993,"identity":"429d7d05-f073-413e-b67e-a2f46e7e0e98","added_by":"auto","created_at":"2026-05-22 07:28:02","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":66817,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eForest plot of factors associated with biopsy adequacy\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure Legend:\u003c/strong\u003e Forest plot displays the adjusted odds ratios (aORs) and 95% confidence intervals for variables included in the multivariable generalized estimating equations (GEE) analysis evaluating biopsy adequacy. The vertical dashed line represents the null value (aOR = 1). Point estimates are shown with black circles and horizontal 95% confidence-interval bars; variables with statistically significant associations (p \u0026lt; 0.05) have blue labels. CT, Computed Tomography; USG, Ultrasound; eGFR, estimated glomerular filtration rate; SBP, systolic blood pressure; DBP, diastolic blood pressure; *Radiologist #1 used as reference, radiologists #2, #3, #4, #5, #7, and #9 had aORs 0.98–1.75 (all p \u0026gt; 0.05), Radiologist 8 was excluded due to insufficient sample size (n=1) \u003csup\u003e# \u003c/sup\u003eactive anticoagulation: use of therapeutic heparin drip, intravenous heparin bridge and subcutaneous low molecular weight heparin (LMWH) bridge for patients previously on warfarin, or direct oral anticoagulants.\u003c/p\u003e","description":"","filename":"Onlinefloatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-9499410/v1/a8cc9bd5b339d9dde2334af1.png"},{"id":109763972,"identity":"1671a5c6-101e-4355-82e0-d74b7e82dbc9","added_by":"auto","created_at":"2026-05-22 07:36:18","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":754128,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9499410/v1/aeed7a20-03d9-4caf-82d4-aca917bf007b.pdf"},{"id":109759994,"identity":"7d2d6882-f52c-44d9-8ece-07d3358bb6d3","added_by":"auto","created_at":"2026-05-22 07:28:02","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":23500,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementarytable.docx","url":"https://assets-eu.researchsquare.com/files/rs-9499410/v1/4789ca35f65b076b8f750169.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eLong-Term Evaluation of Kidney Biopsy Outcomes to Guide Continuous Quality Improvement\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eKidney biopsies are essential in diagnosing, classifying, and managing renal diseases.\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e Additionally, with advances in molecular pathology and genomics, kidney biopsy is increasingly used in research to identify biomarkers and advance personalized medicine in nephrology.\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eDespite its diagnostic utility, kidney biopsies are invasive with inherent risks, including major bleeding that may require transfusion, diagnostic angiogram, or coil embolization, formation of arteriovenous fistula, and, in rare cases, nephrectomy or death.\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e Major complications are rare and have declined over time.\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e,\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e In addition to careful consideration of procedural risk, a kidney biopsy sample must be \u0026ldquo;adequate\u0026rdquo; for accurate diagnosis. Inadequate kidney biopsy risks misclassifying disease, delaying appropriate treatment, and increasing the need for repeat biopsy, thereby increasing healthcare costs and patient burden. In contrast to the declining trend in complications, a recent review of 123,372 native kidney biopsies from years 2005 to 2020 reported rising rates in biopsy inadequacy, attributed to smaller specimen sizes, insufficient cortical tissue, and fewer glomeruli per specimen.\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eAt our institution, we observed fluctuating inadequacy and occasional preventable complications suggesting that both local procedural practices and patient-specific factors may influence outcomes. This highlighted the need to closely examine our biopsy workflow to identify modifiable contributors to performance. Accordingly, this study evaluates clinical, laboratory, radiologic, and procedural factors associated with biopsy outcomes to identify actionable targets for an institution-level quality improvement (QI) initiative to simultaneously enhance overall biopsy adequacy rates and improve patient safety by minimizing complications.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy design and patient selection\u003c/h2\u003e \u003cp\u003eThis was a retrospective cohort study that included adults older than 18 years of age who underwent a clinically indicated native kidney biopsy from January 2014 to December 2023 at the University of Kansas Medical Center (KUMC), a tertiary referral center in Kansas. We excluded allograft and renal mass biopsies.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eBiopsy technique\u003c/h3\u003e\n\u003cp\u003eInterventional radiologists (IR) performed biopsies by real-time ultrasound (USG) or computed tomography (CT) guidance, using a spring-loaded biopsy gun. Complete blood count (CBC), international normalized ratio (INR), and basic metabolic panel (BMP) were required within the last 30 days before the biopsy. The acceptable pre-biopsy levels of hemoglobin, platelet count, and INR were \u0026ge;8.5 g/dL, \u0026ge;100\u0026times;10\u003csup\u003e9\u003c/sup\u003e/L and \u0026le;1.5, respectively. For elective biopsies, the hospitalist service admitted patients overnight for observation. Patients maintained 6 hours of bed rest and avoided strenuous activity for 24 hours. Hemoglobin was measured 5 hours post-biopsy, CBC and BMP the next morning. Hospitalists or nephrologists ordered post-procedure imaging if bleeding was clinically suspected.\u003c/p\u003e\n\u003ch3\u003eData extraction and Definitions\u003c/h3\u003e\n\u003cp\u003eWe reviewed electronic medical records to obtain demographic, radiologic, laboratory, histopathological, procedure-related, and clinical data. We defined pre-biopsy serum creatinine, INR, and platelet count as the most recent values obtained within 30 days, pre-biopsy hemoglobin within 7 days, and post-biopsy hemoglobin obtained 4\u0026ndash;6 hours afterwards. We recorded estimated glomerular filtration rate (eGFR) only in patients with stable creatinine and Chronic Kidney Disease (CKD) stages 3\u0026ndash;5. The laboratory used the Modification of Diet in Renal Disease (MDRD) equation to calculate eGFR before 2021, and the Chronic Kidney Disease Epidemiology Collaboration (2021) equation afterwards. We recorded systolic (SBP) and diastolic blood pressures (DBP) immediately pre-biopsy, and the maximum SBP and DBP within 24 hours after biopsy based on review of all vital signs. We defined post-biopsy hypotension as SBP\u0026thinsp;\u0026lt;\u0026thinsp;100 mm Hg within 24 hours. Kidney length was based on radiology reports within one year of biopsy, and if radiologic reported size was unavailable, we manually measured length from available images. We manually measured cortical thickness from USG images within one year before or after the biopsy, with no data if images were of poor quality. The investigators obtained procedure details from IR reports and specimen details from histopathology reports. We defined \u0026ldquo;active anticoagulation\u0026rdquo; as the use of therapeutic heparin, intravenous heparin bridging (held 4\u0026ndash;6 hours pre-biopsy) and subcutaneous low-molecular-weight- heparin (LMWH) bridging (held 24 hours pre-biopsy) for patients on warfarin (held 5 days, INR\u0026thinsp;\u0026le;\u0026thinsp;1.5), or direct oral anticoagulants (held for 4\u0026ndash;6 doses). We did not consider aspirin, clopidogrel, or prophylactic dosing of pharmacological anticoagulation as part of this definition. We classified biopsies as \u0026ldquo;elective\u0026rdquo; if they were preplanned.\u003c/p\u003e\n\u003ch3\u003eOutcomes\u003c/h3\u003e\n\u003cp\u003eWe defined a major complication as the need for angiography, embolization, or transfusion within 7 days of biopsy. Hematoma detected on imaging within 7 days post-biopsy was a minor complication. For adequacy, we utilized 2 different definitions. We defined adequacy as a composite of \u0026ge; 10 glomeruli in light microscopy (LM), \u003cem\u003eand\u003c/em\u003e \u0026ge; 1 glomerulus for indirect immunofluorescence (IF), \u003cem\u003eand\u003c/em\u003e \u0026ge; 1 glomerulus for electron microscopy (EM). We defined \u0026ldquo;minimal adequacy\u0026rdquo; as \u0026ge; 10 total glomeruli (including LM and IF and EM).\u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e,\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDefinitions of Outcomes\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMajor Complication\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNeed for angiography, embolization, \u003cem\u003eor\u003c/em\u003e transfusion within 7 days of biopsy\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMinor Complication\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHematoma detected on imaging within 7 days post-biopsy\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBiopsy Adequacy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;10 glomeruli in light microscopy (LM), \u003cem\u003eand\u003c/em\u003e \u0026ge;\u0026thinsp;1 glomerulus for indirect immunofluorescence (IF), \u003cem\u003eand\u003c/em\u003e \u0026ge;\u0026thinsp;1 glomerulus for electron microscopy (EM)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMinimal Adequacy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;10 total glomeruli (including LM and IF and EM)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eWe summarized categorical variables using absolute and relative frequencies and continuous variables using the median and interquartile range. We used generalized estimating equations (GEE) with a logistic link function and an independent working correlation structure to account for potential nonindependence of observations from individuals contributing to repeat biopsies. This allowed us to estimate odds ratios of major complication, hematoma, biopsy adequacy, and minimal adequacy (each using a separate model) for covariates selected a priori based on clinical knowledge. To address missing data across all regression models, we used multiple imputation by chained equations with M\u0026thinsp;=\u0026thinsp;20 imputed datasets, as implemented in the \u0026ldquo;mice\u0026rdquo; package, and pooled estimates using Rubin\u0026rsquo;s rules. We set statistical significance at α\u0026thinsp;=\u0026thinsp;0.05 and conducted all analyses in R (v4.4.1). We also analyzed trends in complication and adequacy outcomes over time.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eEthics and Funding\u003c/h2\u003e \u003cp\u003eThis study was approved by the Institutional Review Board of University of Kansas Medical Center (IRB#STUDY00161445) and conducted in accordance with the Declaration of Helsinki; informed consent was waived due to the retrospective design. The clinical and research activities being reported are consistent with the Principles of the Declaration of Istanbul as outlined in the \u0026ldquo;Declaration of Istanbul on Organ Trafficking and Transplant Tourism\u0026rdquo;. All authors declare no conflict of interest.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eBaseline characteristics \u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe included 796 kidney biopsies performed in 763 adult patients. Eleven biopsies in children were excluded. The median age was 54.9 (IQR 37.9\u0026ndash;66.0) years, 447 (56.2%) were females, and the median BMI was 28.9 (IQR 24.6\u0026ndash;34.3) kg/m\u003csup\u003e2\u003c/sup\u003e. Median pre-biopsy hemoglobin was 10.5 (IQR 9.1\u0026ndash;12.6) g/dL, platelet count 231 (IQR 176.0\u0026ndash;299.8) \u0026times;10\u003csup\u003e9\u003c/sup\u003e/L, and INR 1.0 (IQR 1.0\u0026ndash;1.1). Median pre-biopsy serum creatinine was 2.0 (IQR 1.2\u0026ndash;3.5) mg/dL. Of 796 biopsies, 95.4% were US-guided, 4.6% were CT-guided, and 432 (54.3%) were elective biopsies. Median length of the kidney was 11.0 (IQR 10.0\u0026ndash;12) cm and median cortical thickness was 9.6 (IQR 8.1\u0026ndash;10.8) mm. 18-gauge biopsy needles were used in 780 (97.99%) biopsies; 16-gauge biopsy needles were used in 16 (2.01%) biopsies. The median number of passes and cores was 3 each. Patients with acute kidney injury (AKI) or AKI on CKD comprised 18.9% of biopsies. In patients with CKD, eGFR (mL/min/1.73 m\u003csup\u003e2\u003c/sup\u003e) ranged from \u0026ge; 60 in 24%, 45\u0026ndash;59 in 8.2%, 30\u0026ndash;44 in 8.2%, 15-29 in 19.2%, and \u0026lt; 15 in 14.5%. The median eGFR (mL/min/1.73 m\u003csup\u003e2\u003c/sup\u003e) in CKD stage \u0026ge;3 was 31.0 (IQR 19.5\u0026ndash;43.0). Median pre-biopsy SBP was 132.0 (IQR 119.0\u0026ndash;144.0)\u0026nbsp;mm Hg and DBP was 77.0 (IQR 69.0\u0026ndash;87.0) mm Hg. Median peak post-biopsy SBP was 146.0 (133.0\u0026ndash;159.0) mm Hg and DBP was 85.0 (75.0\u0026ndash;95.0) mm Hg. Fifty-two (6.4%) biopsies received active anticoagulation. Seventeen biopsies (2.1%) were repeats for inadequacy and 16 (2.01%) for other clinical indications.\u003c/p\u003e\n\u003cp\u003eBaseline characteristics are described in Table 2.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2.\u003c/strong\u003e Baseline demographic and clinical data.\u003c/p\u003e\n\u003ctable width=\"624\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e\u003cstrong\u003eOverall, \u003cem\u003eN\u003c/em\u003e=796\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003e\u003cstrong\u003eDemographics\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003eAge at biopsy (years)\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e54.9 (37.9\u0026ndash;66.0)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003eSex\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003eFemale\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e447 (56.2)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003eMale\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e349 (43.8)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003eBody mass index (kgm\u003csup\u003e\u0026minus;2\u003c/sup\u003e)\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e28.9 (24.6\u0026ndash;34.3)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003e\u003cstrong\u003eLaboratory measures\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003ePreprocedural hemoglobin (g/dL)\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e10.5 (9.1\u0026ndash;12.6)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003ePreprocedural platelet count (\u0026times;10\u003csup\u003e9\u003c/sup\u003e/L)\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e231.0 (176.0\u0026ndash;299.8)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003ePreprocedural INR\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e1.0 (1.0\u0026ndash;1.1)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003ePreprocedural creatinine (mg/dL)\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e2.0 (1.2\u0026ndash;3.5)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003ePreprocedural estimated glomerular filtration rate (mL/min/1.73 m\u003csup\u003e2\u003c/sup\u003e)\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003e\u0026ge;60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e191/795 (24.0)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003e\u0026lt;60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e604/795 (75.1)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003e45\u0026ndash;59\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e65/795 (8.2)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003e30\u0026ndash;44\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e121/795 (15.2)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003e15\u0026ndash;29\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e153/795 (19.2)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003e\u0026lt;15\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e115/795 (14.5)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003ePreprocedural estimated glomerular filtration rate (mL/min/1.73 m\u003csup\u003e2\u003c/sup\u003e) in CKD stage \u0026ge;3\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e31.0 (19.5\u0026ndash;43.0)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003e\u003cstrong\u003eClinical measures\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003ePreprocedural systolic blood pressure (mm Hg)\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e132.0 (119.0\u0026ndash;144.0)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003ePreprocedural diastolic blood pressure (mm Hg)\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e77.0 (69.0\u0026ndash;87.0)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003ePeak postprocedural systolic blood pressure (mm Hg)\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e146.0 (133.0\u0026ndash;159.0)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003ePeak postprocedural diastolic blood pressure (mm Hg)\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e85.0 (75.0\u0026ndash;95.0)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003eActive Anticoagulation*\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e52 (6.5)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003eElective biopsy\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e432 (54.3)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003eAcute kidney injury \u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e150/795 (18.9)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003e\u003cstrong\u003eRadiologic measures\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003eLength of kidney biopsied (cm)\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e11.0 (10.0\u0026ndash;12.0)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003eCortical thickness of kidney (mm)\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e9.6 (8.1\u0026ndash;10.8)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003eGuidance type\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003eUltrasound\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e759 (95.4)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003eComputed tomography\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e37 (4.6)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003eNumber of passes \u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e3\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"479\"\u003e\n\u003cp\u003eNeedle Gauge \u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\n\u003cp\u003e18-gauge\u003c/p\u003e\n\u003cp\u003e16-gauge\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e780(97.99%)\u003c/p\u003e\n\u003cp\u003e16(2.01%)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eINR, International Normalized Ratio, *active anticoagulation: use of therapeutic heparin drip, intravenous heparin bridge and subcutaneous low molecular weight heparin (LMWH) bridge for patients previously on warfarin, or direct oral anticoagulants.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eOutcomes \u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eComplications:\u003c/strong\u003e Major complications occurred in 82 biopsies (10.3%). Twenty-three (2.9%) biopsies required angiography alone, and 21 (2.6%)required embolization. Blood transfusion was required in 9.8% of biopsies: 32 (4.0%) within 24 hours and 46 (5.8%) after 24 hours. Hypotension developed in 109 (13.7%)biopsies after procedure. Median change in hemoglobin after biopsy was -0.3 (IQR -0.8\u0026ndash;0.2) g/dL. A hemoglobin drop of \u0026gt;1 g/dL was observed in 109 (13.7%)biopsies and hematoma within 7 days post-biopsy was observed in 93 (11.7%) biopsies. (Table 3)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3: \u003c/strong\u003eOutcomes: Complications and Adequacy\u003c/p\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003e\u003cstrong\u003eComplications\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eAt least one major complication\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e82/795 (10.3)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eEmbolization\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e23 (2.9)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eAngiography\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e21 (2.6)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eBlood transfusion (within 24 hours)\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e32/795 (4.0)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eBlood transfusion (within 1\u0026ndash;7 days)\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e46/795 (5.8)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eClinical concern for hypotension (within 24 hours)\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e109/793 (13.7)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eHematoma\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e93 (11.7)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003e\u0026ge;1 g/dL drop in hemoglobin\u0026mdash;n (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e142/724 (19.6)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003e\u003cstrong\u003eSpecimen adequacy\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eBiopsy adequacy\u0026mdash;\u003cem\u003en\u003c/em\u003e (%) *\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e441/755 (58.4)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eMinimal adequacy\u0026mdash;\u003cem\u003en\u003c/em\u003e (%) #\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e669 (84.0)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eNumber of cores \u0026mdash;median\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e3\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eTotal glomeruli count\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e21.5 (14.0\u0026ndash;33.0)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eRe-biopsy for inadequacy\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e17 (2.1)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003e\u003cem\u003eLight microscopy\u003c/em\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eGlomeruli count\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e14.0 (8.0\u0026ndash;20.0)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eSpecimen adequacy\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003csup\u003e1\u003c/sup\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e529/786 (67.3)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003e\u003cem\u003eImmunofluorescence\u003c/em\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eGlomeruli count\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e6.0 (3.0\u0026ndash;10.0)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eSpecimen adequacy\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e677/775 (87.4)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003e\u003cem\u003eElectron microscopy\u003c/em\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eGlomeruli count\u0026mdash;median (IQR)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e2.0 (1.0\u0026ndash;3.5)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"477\"\u003e\n\u003cp\u003eSpecimen adequacy\u0026mdash;\u003cem\u003en\u003c/em\u003e (%)\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"145\"\u003e\n\u003cp\u003e660/742 (88.9)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e*Biopsy adequacy defined as \u0026ge; 10 glomeruli in light microscopy (LM), \u003cem\u003eand\u003c/em\u003e \u0026ge; 1 glomerulus for indirect immunofluorescence (IF), \u003cem\u003eand \u003c/em\u003e\u0026ge; 1 glomerulus for electron microscopy (EM), \u003csup\u003e#\u003c/sup\u003eMinimal adequacy defined as \u0026ge; 10 total glomeruli (including LM and IF and EM), \u003csup\u003e1\u003c/sup\u003eSpecimen adequacy for LM defined as \u0026ge; 10 glomeruli, \u003csup\u003e2\u003c/sup\u003eSpecimen adequacy for IF defined as \u0026ge; 1 glomerulus, \u003csup\u003e3\u003c/sup\u003eSpecimen adequacy for EM defined as \u0026ge; 1 glomerulus\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAdequacy\u003c/strong\u003e: Samples were \u0026ldquo;adequate\u0026rdquo; in 441 (58.4%) biopsies, and \u0026ldquo;minimally adequate\u0026rdquo; in 669 (84.0%) cases. Adequacy rates for LM, EM, and IF were 67.3%,\u0026nbsp;87.4%, and 88.9%, respectively. The median number of total glomeruli was 21.5 (IQR 14.0\u0026ndash;33.0). The median number of glomeruli in LM, IF, and EM were 14.0 (IQR 8.0\u0026ndash;20.0), 6.0 (IQR 3.0\u0026ndash;10.0)\u0026nbsp;and 2.0 (IQR 1.0\u0026ndash;3.5), respectively. (Table 3)\u003c/p\u003e\n\u003cp\u003eFigure 1 illustrates the trends in complication and adequacy rates over time.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure 1.\u003c/strong\u003e\u003cstrong\u003eTrends in major complication and biopsy adequacy rates over time \u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure Legend: \u003c/strong\u003ePanel a: Major complications over time: horizontal axis describes the year of biopsy; vertical axis describes the biopsy counts; the bar graphs represent the rate and percentage of major complications, Panel b: Biopsy adequacy over time: horizontal axis describes the year of biopsy; vertical axis describes the biopsy counts; the bar graphs represent the rate and percentage of biopsy adequacy\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMultivariable GEE analysis of factors associated with major complications and hematoma\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHigher hemoglobin was associated with lower odds of major complication (adjusted OR (aOR) 0.73, 95% CI 0.60\u0026ndash;0.90, p\u003cstrong\u003e=\u003c/strong\u003e0.003\u003cstrong\u003e)\u003c/strong\u003e. Higher platelet count was associated with lower odds of both major complications (aOR 0.88, 95% CI 0.79\u0026ndash;1.00, p\u003cstrong\u003e=\u003c/strong\u003e0.045) and hematoma (aOR 0.86, 95% CI 0.76\u0026ndash;0.99, p\u003cstrong\u003e=\u003c/strong\u003e0.031). AKI (aOR 4.44 (95% CI 1.49\u0026ndash;13.24), p\u003cstrong\u003e=\u003c/strong\u003e0.007) and higher INR (aOR 2.72, 95% CI 1.03\u0026ndash;7.19, p=0.043) had higher odds of major complications. CKD stage 5 had an aOR of 3.09, 95% CI 0.98\u0026ndash;9.69, p=0.053). Higher cortical thickness had higher odds of major complications (aOR 1.22, 95% CI 1.03\u0026ndash;1.44, p=0.019). Biopsies by Radiologist #2 were associated with higher odds of hematoma (aOR 3.12, 95% CI 1.06\u0026ndash;9.16, p=0.038). Age, sex, BMI, USG versus CT guidance, 16g versus 18g, number of passes, preprocedural SBP and DBP, length of the kidney, elective versus emergency biopsy, and active anticoagulation were not associated with major complications or hematoma. (Table 4, Figure 2)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4.\u003c/strong\u003e Multivariable GEE analysis of factors associated with major complications and hematoma\u003c/p\u003e\n\u003ctable width=\"100%\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd rowspan=\"2\" width=\"417\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd colspan=\"2\" width=\"301\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;Major complication\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd colspan=\"2\" width=\"239\"\u003e\n\u003cp\u003e\u003cstrong\u003eHematoma\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003ep-\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003evalue\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003ep-\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003evalue\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003eAge at biopsy (years)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e1.01 (0.99\u0026ndash;1.03)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.47\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e1.00 (0.99\u0026ndash;1.02)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.93\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003eMale vs Female\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e1.39 (0.78\u0026ndash;2.47)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.26\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e0.87 (0.52\u0026ndash;1.43)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.57\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003eBody mass index (kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e0.99 (0.95\u0026ndash;1.03)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.50\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e0.99 (0.95\u0026ndash;1.02)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.38\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003ePreprocedural hemoglobin (g/dL)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e0.73 (0.60\u0026ndash;0.90)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e\u003cstrong\u003e0.003\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e0.98 (0.85\u0026ndash;1.13)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.75\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003ePreprocedural platelet count (\u0026times;10\u003csup\u003e9\u003c/sup\u003e/L)\u003csup\u003e1\u003c/sup\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e0.88 (0.79\u0026ndash;1.00)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e\u003cstrong\u003e0.045\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e0.86 (0.76\u0026ndash;0.99)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e\u003cstrong\u003e0.031\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003ePreprocedural INR\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e2.72 (1.03\u0026ndash;7.19)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e\u003cstrong\u003e0.043\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e1.37 (0.43\u0026ndash;4.31)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.59\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003eRadiologist\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003e#2 vs #1\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e1.80 (0.54\u0026ndash;5.99)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.34\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e3.12 (1.06\u0026ndash;9.16)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e\u003cstrong\u003e0.038\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003eGuidance type\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003eComputed tomography vs Ultrasound\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e1.76 (0.64\u0026ndash;4.87)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.28\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e1.38 (0.51\u0026ndash;3.74)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.53\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003eNumber of passes\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e0.99 (0.75\u0026ndash;1.31)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.95\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e1.05 (0.80\u0026ndash;1.38)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.72\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003eMaximum core length (cm)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e1.24 (0.86\u0026ndash;1.81)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.25\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e1.14 (0.80\u0026ndash;1.62)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.46\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003eNeedle gauge\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003e18 vs 16\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e0.50 (0.10\u0026ndash;2.50)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.40\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e0.29 (0.07\u0026ndash;1.14)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.077\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003eLength of kidney biopsied (cm)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e0.90 (0.74\u0026ndash;1.08)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.24\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e1.02 (0.87\u0026ndash;1.20)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.80\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003eCortical thickness of kidney (mm)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e1.22 (1.03\u0026ndash;1.44)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e\u003cstrong\u003e0.019\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e1.05 (0.92\u0026ndash;1.19)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.47\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003eEs0timated glomerular filtration rate (mL/min/1.73 m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003e45\u0026ndash;59 vs \u0026ge;60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e1.61 (0.33\u0026ndash;7.95)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.56\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e1.11 (0.39\u0026ndash;3.15)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.85\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003e30\u0026ndash;44 vs \u0026ge;60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e1.43 (0.37\u0026ndash;5.50)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e1.59 (0.65\u0026ndash;3.88)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.31\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003e15\u0026ndash;29 vs \u0026ge;60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e1.86 (0.60\u0026ndash;5.77)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.28\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e1.43 (0.65\u0026ndash;3.17)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.37\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003e\u0026lt;15 vs \u0026ge;60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e3.09 (0.98\u0026ndash;9.69)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.053\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e1.67 (0.67\u0026ndash;4.18)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.27\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003eAcute kidney injury\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e4.44 (1.49\u0026ndash;13.24)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e\u003cstrong\u003e0.007\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e1.51 (0.65\u0026ndash;3.53)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.34\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003eElective biopsy\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e0.65 (0.34\u0026ndash;1.25)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.19\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e0.82 (0.45\u0026ndash;1.49)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.51\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003ePreprocedural systolic blood pressure (mm Hg)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e1.00 (0.98\u0026ndash;1.02)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.89\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e1.00 (0.99\u0026ndash;1.02)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.90\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003ePreprocedural diastolic blood pressure (mm Hg)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e1.02 (1.00\u0026ndash;1.04)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.11\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e1.02 (1.00\u0026ndash;1.04)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.10\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"417\"\u003e\n\u003cp\u003eActive anticoagulation\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"179\"\u003e\n\u003cp\u003e1.15 (0.43\u0026ndash;3.08)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"122\"\u003e\n\u003cp\u003e0.78\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"149\"\u003e\n\u003cp\u003e1.60 (0.71\u0026ndash;3.59)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"90\"\u003e\n\u003cp\u003e0.26\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eGEE, generalized estimating equations; Major complications, need for angiography, embolization, or transfusion within seven days of biopsy; aOR, adjusted Odds Ratio; INR, International Normalized Ratio; \u003csup\u003e1\u003c/sup\u003ePlatelet count was rescaled so that each unit represents a change of 50\u0026times;10\u003csup\u003e9\u003c/sup\u003e/L for interpretation of odds ratio, \u003csup\u003e2\u003c/sup\u003eRadiologist #1 used as reference, For major complications: radiologists #3\u0026ndash;#9 had aORs 0.91\u0026ndash;3.95 (all p \u0026gt; 0.05)., For hematoma: only Radiologist #2 showed a significant association; others not significant., Radiologist #8 was excluded due to insufficient sample size (n=1), \u003csup\u003e3\u003c/sup\u003eactive anticoagulation: use of therapeutic heparin drip, intravenous heparin bridge and subcutaneous low molecular weight heparin (LMWH) bridge for patients previously on warfarin, or direct oral anticoagulants.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure 2: Forest plot of factors associated with major complications \u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure Legend:\u003c/strong\u003e Forest plot displays the adjusted odds ratios (aORs) and 95% confidence intervals for variables included in the multivariable generalized estimating equations (GEE) analysis evaluating major biopsy complications. The vertical dashed line represents the null value (aOR = 1). Point estimates are shown with black circles and horizontal 95% confidence-interval bars; variables with statistically significant associations (p \u0026lt; 0.05) have blue labels. CT, Computed Tomography; USG, Ultrasound; eGFR, estimated glomerular filtration rate; SBP, systolic blood pressure; DBP, diastolic blood pressure; *Radiologist #1 used as reference, radiologists #2, #3, #4, #5, #6, #7, and #9 had aORs 0.98\u0026ndash;1.75 (all p \u0026gt; 0.05), Radiologist 8 was excluded due to insufficient sample size (n=1); \u003csup\u003e#\u003c/sup\u003eactive anticoagulation: use of therapeutic heparin drip, intravenous heparin bridge and subcutaneous low molecular weight heparin (LMWH) bridge for patients previously on warfarin, or direct oral anticoagulants.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSensitivity analysis for major complications using dichotomous pre-biopsy hemoglobin, excluding biopsies with INR\u0026gt;1.5 and/or platelet count \u0026lt;100\u0026times;10\u003csup\u003e9\u003c/sup\u003e/L\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHemoglobin \u0026lt;10 g/dL (aOR 2.4, 95% CI 1.17-5.06, p\u003cstrong\u003e=\u003c/strong\u003e0.017) and AKI (aOR 3.73, 95% CI 1.20-11.56, p=0.023) was associated with major complications. Cortical thickness, platelet count, and INR showed no association to major complications. (Table S1)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMultivariable GEE analysis of factors associated with biopsy adequacy\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eBiopsies performed by Radiologist #6 (aOR 2.13, 95% CI 1.53\u0026ndash;2.98, p\u0026lt;0.001) and longer maximum core length (aOR 2.59, 95% CI 1.47\u0026ndash;4.55, p\u0026lt;0.001) were associated with greater biopsy adequacy. Higher BMI was associated with lower biopsy adequacy (aOR 0.97, 95% CI 0.94\u0026ndash;0.99, p\u003cstrong\u003e=\u003c/strong\u003e0.003). Biopsies performed by Radiologist #4 (aOR 2.24, 95% CI 1.07\u0026ndash;4.66, p=0.031) and #6 (aOR 6.09, 95% CI 2.74\u0026ndash;13.53, p=\u0026lt;0.001) were associated with greater \u0026ldquo;minimal adequacy\u0026rdquo;. Age, sex, USG versus CT guidance, 16g versus 18g, number of passes, cortical thickness, kidney length, elective versus emergency biopsy, AKI, and CKD stages were not associated with biopsy adequacy or minimal adequacy. (Table 5, Figure 3)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 5.\u003c/strong\u003e Multivariable GEE analysis of factors associated with biopsy adequacy\u003c/p\u003e\n\u003ctable width=\"678\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd rowspan=\"2\" width=\"223\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd colspan=\"2\" width=\"207\"\u003e\n\u003cp\u003e\u003cstrong\u003eBiopsy adequacy\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd colspan=\"2\" width=\"249\"\u003e\n\u003cp\u003e\u003cstrong\u003eMinimal adequacy\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003ep-\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003evalue\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003ep-\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003evalue\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003eAge at biopsy (years)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e0.99 (0.98\u0026ndash;1.00)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e0.10\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e0.99 (0.98\u0026ndash;1.00)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e0.21\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003eMale\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e0.79 (0.57\u0026ndash;1.09)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e0.15\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e0.79 (0.53\u0026ndash;1.19)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e0.26\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003eBody mass index (kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e0.97 (0.94\u0026ndash;0.99)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e\u003cstrong\u003e0.003\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e0.98 (0.95\u0026ndash;1.01)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e0.22\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003eRadiologist\u003csup\u003e1\u003c/sup\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003e#4 vs #1\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e1.15 (0.63\u0026ndash;2.08)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e0.65\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e2.24 (1.07\u0026ndash;4.66)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e\u003cstrong\u003e0.031\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003e#6 vs #1\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e2.59 (1.47\u0026ndash;4.55)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026lt;0.001\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e6.09 (2.74\u0026ndash;13.53)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026lt;0.001\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003eGuidance type\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003eComputed tomography vs Ultrasound\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e0.83 (0.41\u0026ndash;1.68)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e0.60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e0.44 (0.19\u0026ndash;1.02)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e0.056\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003eNumber of passes\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e1.21 (0.95\u0026ndash;1.55)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e0.12\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e0.94 (0.72\u0026ndash;1.21)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e0.61\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003eMaximum core length (cm)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e2.13 (1.53\u0026ndash;2.98)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026lt;0.001\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e1.84 (1.16\u0026ndash;2.91)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e\u003cstrong\u003e0.009\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003eNeedle gauge\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003e18 vs 16\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e1.72 (0.44\u0026ndash;6.66)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e0.43\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e2.53 (0.77\u0026ndash;8.26)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e0.12\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003eLength of kidney biopsied (cm)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e1.08 (0.96\u0026ndash;1.21)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e0.22\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e0.94 (0.81\u0026ndash;1.10)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e0.45\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003eCortical thickness of kidney (mm)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e0.96 (0.87\u0026ndash;1.07)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e0.47\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e0.93 (0.81\u0026ndash;1.08)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e0.35\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003eEstimated glomerular filtration rate (mL/min/1.73 m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003e45\u0026ndash;59 vs \u0026ge;60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e0.78 (0.41\u0026ndash;1.48)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e0.44\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e1.26 (0.51\u0026ndash;3.10)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e0.62\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003e30\u0026ndash;44 vs \u0026ge;60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e0.86 (0.50\u0026ndash;1.47)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e0.57\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e0.87 (0.44\u0026ndash;1.71)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e0.69\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003e15\u0026ndash;29 vs \u0026ge;60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e0.90 (0.55\u0026ndash;1.47)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e0.67\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e0.96 (0.49\u0026ndash;1.86)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e0.90\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003e\u0026lt;15 vs \u0026ge;60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e0.84 (0.48\u0026ndash;1.47)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e0.53\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e0.69 (0.34\u0026ndash;1.39)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e0.30\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003eAcute kidney injury\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e1.12 (0.66\u0026ndash;1.89)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e0.68\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e1.13 (0.56\u0026ndash;2.29)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e0.74\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"223\"\u003e\n\u003cp\u003eElective biopsy\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"127\"\u003e\n\u003cp\u003e1.35 (0.95\u0026ndash;1.93)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"80\"\u003e\n\u003cp\u003e0.10\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e0.92 (0.58\u0026ndash;1.45)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"124\"\u003e\n\u003cp\u003e0.71\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eGEE, generalized estimating equations; INR, International Normalized Ratio; \u0026sup1;Radiologist #1 used as reference, For biopsy adequacy: radiologists #2, #3, #5, #7, and #9 had aORs 0.98\u0026ndash;1.75 (all p \u0026gt; 0.05), For minimal adequacy: radiologists #2, #3, #5, #7, and #9 had aORs 1.02\u0026ndash;1.61 (all p \u0026gt; 0.05), Only radiologists #4 and #6 were significantly associated with biopsy adequacy outcomes, Radiologist #8 was excluded due to insufficient sample size (n=1)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure 3: Forest plot of factors associated with biopsy adequacy\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure Legend:\u003c/strong\u003e Forest plot displays the adjusted odds ratios (aORs) and 95% confidence intervals for variables included in the multivariable generalized estimating equations (GEE) analysis evaluating biopsy adequacy. The vertical dashed line represents the null value (aOR = 1). Point estimates are shown with black circles and horizontal 95% confidence-interval bars; variables with statistically significant associations (p \u0026lt; 0.05) have blue labels. CT, Computed Tomography; USG, Ultrasound; eGFR, estimated glomerular filtration rate; SBP, systolic blood pressure; DBP, diastolic blood pressure; *Radiologist #1 used as reference, radiologists #2, #3, #4, #5, #7, and #9 had aORs 0.98\u0026ndash;1.75 (all p \u0026gt; 0.05), Radiologist 8 was excluded due to insufficient sample size (n=1) \u003csup\u003e# \u003c/sup\u003eactive anticoagulation: use of therapeutic heparin drip, intravenous heparin bridge and subcutaneous low molecular weight heparin (LMWH) bridge for patients previously on warfarin, or direct oral anticoagulants.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this large single-center retrospective study of nearly 800 native kidney biopsies for over a decade, we observed an overall major complication rate of 10.3%, primarily associated with lower pre-biopsy hemoglobin and platelet count, elevated INR, and presence of AKI and CKD 5. Only 58.4% of biopsies were adequate, with a striking association between proceduralist identity and adequacy, in addition to longer biopsy cores, and lower BMI. Major complication rates declined over time, likely reflecting the impact of prior QI efforts, whereas biopsy adequacy remained largely unchanged.\u003c/p\u003e\n\u003cp\u003eThe major complication and the individual angiography and embolization rates in this cohort were higher than those reported in previous studies\u003csup\u003e3,4\u003c/sup\u003e. Two meta-analyses of native kidney biopsies studies conducted worldwide report blood transfusion rates of 0.9%-1.6%, embolization of 0.3%, and angiography of 0.62%.\u003csup\u003e3,4\u003c/sup\u003e Major complication rate in our study however, declined over the years from 14.5% in 2014 to 2.8% in 2023, approaching the complication rate described in literature. The hematoma rate in biopsies that had post-biopsy imaging was 11.9%, similar to the rate reported in a meta-analysis.\u003csup\u003e3\u003c/sup\u003e This likely reflects our selective imaging approach, in contrast to studies using routine ultrasound—which detect substantially more, often clinically insignificant, hematomas.\u003csup\u003e9,10\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003eThis study found that hemoglobin \u0026gt;10 g/dL was associated with lower odds of major complications. Anemia worsens bleeding due to functional platelet dysfunction and decreased margination with increased laminar platelet flow when hematocrit is low.\u003csup\u003e11,12\u003c/sup\u003eAdditionally, anemia may reflect an inflammatory systemic disease or advanced kidney disease, potentially serving as a proxy for other risk factors for bleeding, including uremic platelet dysfunction. Higher hemoglobin also decreases the clinical trigger to transfuse in response to post-biopsy hemoglobin drop. A meta-analysis found that pre-biopsy hemoglobin of ≥12 g/dL was associated with a lower blood transfusion rate (0.5% vs 2.6%, p=0.001).\u003csup\u003e4\u003c/sup\u003e Higher platelet count was protective against complications in our study, consistent with previous studies.\u003csup\u003e8,13,14\u003c/sup\u003e. Elevated INR was also associated with 2.84-fold higher odds of major complications. Complications were especially higher among biopsies with a platelet count \u0026lt;100×10\u003csup\u003e9\u003c/sup\u003e/L (19.35%) and INR of \u0026gt;1.5 (23.8%). \u0026nbsp;In the sensitivity analysis that excluded biopsies with platelet count of \u0026lt;100 ×10\u003csup\u003e9\u003c/sup\u003e/L and INR \u0026gt;1.5, INR and platelet count were not associated with complications, reiterating the safety of these cut-offs.\u003c/p\u003e\n\u003cp\u003eAKI was associated with major biopsy complications in our cohort, and this association is well known.\u003csup\u003e3,4,8,14–16\u003c/sup\u003e In a study of hospitalized acute kidney disease patients undergoing kidney biopsy, 8% required blood transfusion, and 2% required intervention, which is higher than general complication rate.\u003csup\u003e17\u003c/sup\u003e AKI patients are more likely to be critically ill with other systemic illnesses, which may explain the higher risk of bleeding complications. CKD stage 5 had increased odds of major complication in our cohort, although not reaching significance. In a study of kidney biopsy in patients with an eGFR \u0026lt;15 ml/min/m\u003csup\u003e2\u003c/sup\u003e, 28% had complications, including blood transfusion and intervention.\u003csup\u003e18\u003c/sup\u003e This higher bleeding complication can be explained by the acquired platelet dysfunction seen in advanced uremia.\u003csup\u003e19\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003eHigher blood pressure was not associated with complications in our study. Hypertension, when defined as SBP higher than 160 mm Hg, has been associated with complications, although a meta-analysis failed to show an increased risk with SBP \u0026gt;130 mm Hg.\u003csup\u003e4,15,20,21\u003c/sup\u003e Median blood pressure in our study was well controlled and within protocol threshold (\u0026lt;150/90 mm Hg), reflecting real-world practice. Notably, inpatient blood pressure does not consistently represent true blood pressure and is subject to several confounding physiological and hospital environmental factors.\u003csup\u003e22\u003c/sup\u003e Hematoma was significantly more with biopsies by Radiologist #2, although not associated with major complications. Age, sex, and BMI were not associated with complications unlike some other studies that have shown an association of female sex and advanced age with complications.\u003csup\u003e8,16,23\u003c/sup\u003e,\u003csup\u003e14\u003c/sup\u003e Higher cortical thickness was associated with major complications, which was unexpected; however, the clinical significance of this finding is limited due to measurement error from manually assessing limited or poor-quality USG images. This is also demonstrated by the fact that cortical thickness was not associated with major complications in sensitivity analysis. Biopsy needle gauge (16-gauge vs 18-gauge) \u0026nbsp;was not associated with complications; however, this comparison is not reliable due to the small number of biopsies performed with 16-gauge (2%). Prior studies demonstrate comparable complication risks between the two needle sizes.\u003csup\u003e24–26\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003eKDIGO and Banff recommend 8–10 glomeruli ≥10 glomeruli with 2 arteries for native and transplant biopsies, respectively.\u003csup\u003e6,7\u003c/sup\u003e However, these guidelines do not specify whether the thresholds apply only to LM or also to IF/EM. We defined adequacy by requiring sufficient glomeruli on LM, along with minimum glomerular counts on IF and EM to ensure each modality could be meaningfully interpreted and contribute to diagnostically adequate tissue across the spectrum of kidney diseases. Only 58.4% of biopsies in this cohort were “adequate,” and 84% were “minimally adequate,” per our defined methods. A retrospective study of 123,372 native kidney biopsies analyzed at Arkana Laboratories from 2005 to 2020 reported an increasing rate of inadequate biopsy samples, rising from 2% in 2005 to 14% in 2020.\u003csup\u003e5\u003c/sup\u003e The adequacy rates in our study remained predominantly similar from 2016 to 2023, with a maximum adequacy of 65.5% achieved in 2020. Longer biopsy core, reflecting greater biopsy depth, was associated with higher adequacy suggesting shallower biopsies contributed to inadequate samples. Higher total core length has been shown to result in a higher glomerular yield.\u003csup\u003e27\u003c/sup\u003e Very deep biopsies, however, predominantly sample the medulla, missing the cortex, whereas superficial biopsies sample the cortex incompletely. The optimal biopsy starts at the outer cortex and has adequate depth in order to obtain sufficient glomeruli, while avoiding complications. Deep medullary biopsies cause more bleeding due to the presence of larger vessels.\u003csup\u003e27,28\u003c/sup\u003e The relationship of biopsy depth and adequacy also depends on biopsy angle, \u0026nbsp;as tangential approach has better adequacy and lower complications compared to perpendicular approach.\u003csup\u003e29\u003c/sup\u003e Calculating optimal depth of biopsy using patient body weight and height improved outcomes in one study.\u003csup\u003e30\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003eProceduralist identity significantly influenced adequacy. Radiologist #6 had the highest odds of adequate biopsy, and #4 and #6 had higher odds of obtaining a minimally adequate biopsy. This finding is novel, and it underscores the critical role of the individual proceduralist, as several factors are operator-dependent and unique to individual techniques and experience. While biopsies were traditionally performed by nephrologists and in recent years are more often performed by radiologists, this appears less important than individual proceduralist experience. Some studies have shown nephrologists to have fewer miss rates compared to radiologists, while others have shown similar adequacy rates.\u003csup\u003e5,31–33\u003c/sup\u003e Higher BMI was associated with lower adequacy, consistent with a study that showed lower glomeruli count in obese compared to non-obese patient biopsies.\u003csup\u003e34\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003eWe could not assess the association of needle gauge with adequacy, as very few biopsies were performed with 16-gauge. 16-guage needles provide higher glomeruli count than 18-gauge with greater percentage of adequate biopsy samples.\u003csup\u003e25\u003c/sup\u003e 18-guage needle has a diameter of 350 μm, only slightly larger than the average glomerular diameter (250 μm), whereas the 16-gauge needle measures 700 μm, supporting its use for improved glomerular yield.\u003csup\u003e35\u003c/sup\u003e As the gauge size increased from 14 G to 20 G, Nissen et al. observed a decline in glomerular count from 25 ± 0.9/cm to 2 ± 1.0/cm (mean ± SEM).\u003csup\u003e5\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003eThe overarching aim of this study is to implement QI initiatives. Although complication rates improved, this was not paralleled by gains in adequacy rates, possibly due to proceduralists performing shallower biopsies with an 18-gauge needle to minimize complications. Our goal, as part of ongoing QI, will be to optimize adequacy rates to 90% while continuing to minimize complications: we feel the most impactful intervention is targeted training by radiologists with highest adequacy rates that involves learning from their procedural nuances including angle and depth of biopsy. Utilizing real-time bedside scanning microscope to confirm adequate glomerular sampling can be useful.\u003csup\u003e31,36\u003c/sup\u003e Similarly, assessment of biopsies using web-based tools to analyze photographs taken with smartphones and utilizing machine learning algorithms to analyze the cortical percentage can improve adequacy.\u003csup\u003e37–39\u003c/sup\u003e Switching to 16-gauge will best balance complications and adequacy. Complications can be further minimized by implementing a specific protocol for patients at higher risk (AKI, CKD 5), including a stricter pre-biopsy hemoglobin of\u0026nbsp;³10 g/dL, avoiding biopsies in patients with INR\u0026gt;1.5 and platelet count \u0026lt;100×10\u003csup\u003e9\u003c/sup\u003e/L, and performing eligible tests closer to elective biopsy. Pre-biopsy use of desmopressin 0.3-0.4 mcg/kg in the minutes just prior to biopsy was used in selected patients, based on theoretical and limited clinical evidence of reduced bleeding in advanced CKD.\u003csup\u003e40,41\u003c/sup\u003e\u0026nbsp; The next phase in our QI project will analyze the benefits of desmopressin in a larger patient cohort.\u003c/p\u003e\n\u003cp\u003eThe strength of this study is the large sample size and extensive analysis of variables that can affect both biopsy complications and adequacy.\u0026nbsp;Importantly, our findings provide real, center-specific data to guide future QI efforts. The limitations are the inherent flaws of a retrospective study and limited applicability due to single-center design. Kidney length and cortical thickness were manually measured, and subject to interobserver variability and possible inaccuracies due to poor imaging quality. We did not measure the angle of biopsy, and assessing the angle based on available images is challenging, if not impossible. Lastly, although there was missing data, we managed this by multiple imputation methods.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn conclusion, in this study of native kidney biopsies over a decade, the overall major complication rate declined with earlier QI initiatives. Biopsy adequacy, however, remained suboptimal, with an inadequacy rate of 40% and no significant improvement over time\u0026nbsp;— emphasizing the need for continued, targeted efforts to optimize adequacy. Based on our finding of higher risk of complications in patients with AKI, CKD stage 5 and low hemoglobin, we plan to implement measures to further improve safety in this high-risk group. Peer-training by specific proceduralists—a key determinant of adequacy—will guide future QI efforts for adequacy.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003col\u003e\n \u003cli\u003eStudy approval statement: This study was approved by the Institutional Review Board of University of Kansas Medical Center (IRB#STUDY00161445) and conducted in accordance with the Declaration of Helsinki\u003c/li\u003e\n \u003cli\u003eConsent to participate statement: Informed consent was waived by the IRB of University of Kansas Medical Center (IRB#STUDY00161445) due to the retrospective design\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication:\u0026nbsp;\u003c/strong\u003eNot applicable\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials:\u0026nbsp;\u003c/strong\u003eThe data that support the findings of this study are openly available in \u0026ldquo;figshare\u0026rdquo; at https://doi.org/10.6084/m9.figshare.31222999\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e: The authors declare that they have no competing interests\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of Interest Statement:\u0026nbsp;\u003c/strong\u003eThe authors have no conflicts of interest to declare\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e This study was not supported by any sponsor or funder\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNG: Led data extraction, supervised the project, managed project administration, and wrote the original draft of the manuscript.\u003c/p\u003e\n\u003cp\u003eMA: Performed statistical analyses, provided methodological support, prepared figures, and critically reviewed the manuscript.\u003c/p\u003e\n\u003cp\u003eMC: Contributed to data extraction and reviewed the manuscript.\u003c/p\u003e\n\u003cp\u003ePP: Contributed to data extraction and reviewed the manuscript.\u003c/p\u003e\n\u003cp\u003eCS: Contributed to data extraction and reviewed the manuscript.\u003c/p\u003e\n\u003cp\u003eMZ: Contributed to data extraction and reviewed the manuscript.\u003c/p\u003e\n\u003cp\u003eGG: Contributed to data extraction and reviewed the manuscript.\u003c/p\u003e\n\u003cp\u003eJA: Provided statistical expertise and analysis, prepared figures, and reviewed the manuscript.\u003c/p\u003e\n\u003cp\u003eDJ: Conceived and conceptualized the project, provided oversight and methodological support, and critically revised the manuscript.\u003c/p\u003e\n\u003cp\u003eRM: Conceived and oversaw the project, designed the study, managed project administration, provided methodological support, and critically revised the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e: The authors declare that they have no competing interests\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eDhaun N, Bellamy CO, Cattran DC, Kluth DC. Utility of renal biopsy in the clinical management of renal disease. Kidney Int. 2014;85(5):1039\u0026ndash;48. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1038/ki.2013.512\u003c/span\u003e\u003cspan address=\"10.1038/ki.2013.512\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ede Boer IH, Alpers CE, Azeloglu EU, et al. Rationale and design of the Kidney Precision Medicine Project. Kidney Int. 2021;99(3):498\u0026ndash;510. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.kint.2020.08.039\u003c/span\u003e\u003cspan address=\"10.1016/j.kint.2020.08.039\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePoggio ED, McClelland RL, Blank KN, et al. Systematic Review and Meta-Analysis of Native Kidney Biopsy Complications. Clin J Am Soc Nephrol. 2020;15(11):1595. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.2215/CJN.04710420\u003c/span\u003e\u003cspan address=\"10.2215/CJN.04710420\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCorapi KM, Chen JLT, Balk EM, Gordon CE. Bleeding complications of native kidney biopsy: a systematic review and meta-analysis. Am J Kidney Dis. 2012;60(1):62\u0026ndash;73. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1053/j.ajkd.2012.02.330\u003c/span\u003e\u003cspan address=\"10.1053/j.ajkd.2012.02.330\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNissen CJ, Moreno V, Davis VG, Walker PD. Increasing Incidence of Inadequate Kidney Biopsy Samples Over Time: A 16-Year Retrospective Analysis From a Large National Renal Biopsy Laboratory. Kidney Int Rep. 2022;7(2):251\u0026ndash;8. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.ekir.2021.11.026\u003c/span\u003e\u003cspan address=\"10.1016/j.ekir.2021.11.026\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKidney Disease: Improving Global Outcomes (KDIGO) Glomerular Diseases Work Group. KDIGO 2021 Clinical Practice Guideline for the Management of Glomerular Diseases. Kidney Int. 2021;100(4S):S1\u0026ndash;276. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.kint.2021.05.021\u003c/span\u003e\u003cspan address=\"10.1016/j.kint.2021.05.021\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRoufosse C, Naesens M, Haas M, et al. The Banff 2022 Kidney Meeting Work Plan: Data-driven refinement of the Banff Classification for renal allografts. Am J Transpl. 2024;24(3):350\u0026ndash;61. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.ajt.2023.10.031\u003c/span\u003e\u003cspan address=\"10.1016/j.ajt.2023.10.031\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMonahan H, Gunderson T, Greene E, Schmit G, Atwell T, Schmitz J. Risk factors associated with significant bleeding events after ultrasound-guided percutaneous native renal biopsies: a review of 2204 cases. Abdom Radiol. 2019;44(6):2316\u0026ndash;22. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s00261-019-01962-z\u003c/span\u003e\u003cspan address=\"10.1007/s00261-019-01962-z\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePalsson R, Short SAP, Kibbelaar ZA, et al. Bleeding Complications After Percutaneous Native Kidney Biopsy: Results From the Boston Kidney Biopsy Cohort. Kidney Int Rep. 2020;5(4):511\u0026ndash;8. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.ekir.2020.01.012\u003c/span\u003e\u003cspan address=\"10.1016/j.ekir.2020.01.012\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eXu S, Xiong B, Lin S, Li Q, Wang L, Zhao W. Predictors of perirenal haematoma post-percutaneous ultrasound-guided renal biopsy. J Int Med Res. 2021;49(11):03000605211058377. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1177/03000605211058377\u003c/span\u003e\u003cspan address=\"10.1177/03000605211058377\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eValles J, Santos MT, Aznar J, et al. Erythrocytes metabolically enhance collagen-induced platelet responsiveness via increased thromboxane production, adenosine diphosphate release, and recruitment. Blood. 1991;78(1):154\u0026ndash;62.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTuritto VT, Weiss HJ. Red blood cells: their dual role in thrombus formation. Science. 1980;207(4430):541\u0026ndash;3. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1126/science.7352265\u003c/span\u003e\u003cspan address=\"10.1126/science.7352265\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKajawo S, Ekrikpo U, Moloi MW, et al. A Systematic Review of Complications Associated With Percutaneous Native Kidney Biopsies in Adults in Low- and Middle-Income Countries. Kidney Int Rep. 2021;6(1):78\u0026ndash;90. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.ekir.2020.10.019\u003c/span\u003e\u003cspan address=\"10.1016/j.ekir.2020.10.019\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eXu Dmin, Chen M, de Zhou F, Zhao Mhui. Risk Factors for Severe Bleeding Complications in Percutaneous Renal Biopsy. Am J Med Sci. 2017;353(3):230\u0026ndash;5. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.amjms.2016.12.019\u003c/span\u003e\u003cspan address=\"10.1016/j.amjms.2016.12.019\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKorbet SM, Volpini KC, Whittier WL. Percutaneous Renal Biopsy of Native Kidneys: A Single-Center Experience of 1,055 Biopsies. Am J Nephrol. 2014;39(2):153\u0026ndash;62. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1159/000358334\u003c/span\u003e\u003cspan address=\"10.1159/000358334\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePalsson R, Short SAP, Kibbelaar ZA, et al. Bleeding Complications After Percutaneous Native Kidney Biopsy: Results From the Boston Kidney Biopsy Cohort. Kidney Int Rep. 2020;5(4):511\u0026ndash;8. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.ekir.2020.01.012\u003c/span\u003e\u003cspan address=\"10.1016/j.ekir.2020.01.012\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMoledina DG, Luciano RL, Kukova L, et al. Kidney Biopsy\u0026ndash;Related Complications in Hospitalized Patients with Acute Kidney Disease. Clin J Am Soc Nephrol. 2018;13(11):1633\u0026ndash;40. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.2215/CJN.04910418\u003c/span\u003e\u003cspan address=\"10.2215/CJN.04910418\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAlkadi MM, Abuhelaiqa EA, Thappy SB, et al. Kidney Biopsy in Patients With Markedly Reduced Kidney Function. Kidney Int Rep. 2022;7(11):2505\u0026ndash;8. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.ekir.2022.08.004\u003c/span\u003e\u003cspan address=\"10.1016/j.ekir.2022.08.004\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSohal AS, Gangji AS, Crowther MA, Treleaven D. Uremic bleeding: Pathophysiology and clinical risk factors. Thromb Res. 2006;118(3):417\u0026ndash;22. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.thromres.2005.03.032\u003c/span\u003e\u003cspan address=\"10.1016/j.thromres.2005.03.032\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eShidham GB, Siddiqi N, Beres JA, et al. Clinical risk factors associated with bleeding after native kidney biopsy. Nephrology. 2005;10(3):305\u0026ndash;10. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1111/j.1440-1797.2005.00394.x\u003c/span\u003e\u003cspan address=\"10.1111/j.1440-1797.2005.00394.x\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKriegshauser JS, Patel MD, Young SW, Chen F, Eversman WG, Chang YHH. Risk of Bleeding after Native Renal Biopsy as a Function of Preprocedural Systolic and Diastolic Blood Pressure. J Vasc Interv Radiol. 2015;26(2):206\u0026ndash;12. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.jvir.2014.10.020\u003c/span\u003e\u003cspan address=\"10.1016/j.jvir.2014.10.020\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBress AP, Anderson TS, Flack JM, et al. The Management of Elevated Blood Pressure in the Acute Care Setting: A Scientific Statement From the American Heart Association. Hypertension. 2024;81(8):e94\u0026ndash;106. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1161/HYP.0000000000000238\u003c/span\u003e\u003cspan address=\"10.1161/HYP.0000000000000238\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAnpalahan A, Malacova E, Hegerty K et al. Bleeding Complications of Percutaneous Kidney Biopsy: Does Gender Matter? \u003cem\u003eKidney360\u003c/em\u003e. 2021;2(8):1308\u0026ndash;1312. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.34067/KID.0002432021\u003c/span\u003e\u003cspan address=\"10.34067/KID.0002432021\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMai J, Yong J, Dixson H, et al. Is bigger better? A retrospective analysis of native renal biopsies with 16 Gauge versus 18 Gauge automatic needles. Nephrology. 2013;18(7):525\u0026ndash;30. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1111/nep.12093\u003c/span\u003e\u003cspan address=\"10.1111/nep.12093\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eXie W, Xu J, Xie Y, et al. Adequacy and complication rates of percutaneous renal biopsy with 18- vs. 16-gauge needles in native kidneys in Chinese individuals. BMC Nephrol. 2020;21(1):337. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1186/s12882-020-01987-3\u003c/span\u003e\u003cspan address=\"10.1186/s12882-020-01987-3\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRoth R, Parikh S, Makey D, et al. When Size Matters: Diagnostic Value of Kidney Biopsy according to the Gauge of the Biopsy Needle. Am J Nephrol. 2013;37(3):249\u0026ndash;54. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1159/000347219\u003c/span\u003e\u003cspan address=\"10.1159/000347219\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTorigoe K, Sakamoto R, Abe S, Muta K, Mukae H, Nishino T. Factors Associated with Glomerular Yield in Percutaneous Kidney Biopsy. J Clin Med. 2023;12(12):3877. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3390/jcm12123877\u003c/span\u003e\u003cspan address=\"10.3390/jcm12123877\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBeckingham IJ, Nicholson ML, Bell PR. Analysis of factors associated with complications following renal transplant needle core biopsy. Br J Urol. 1994;73(1):13\u0026ndash;5. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1111/j.1464-410x.1994.tb07449.x\u003c/span\u003e\u003cspan address=\"10.1111/j.1464-410x.1994.tb07449.x\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSawicka K, Hassan N, Dumaine C, et al. Direction of the Biopsy Needle in Ultrasound-Guided Renal Biopsy Impacts Specimen Adequacy and Risk of Bleeding. Can Assoc Radiol J. 2019;70(4):361\u0026ndash;6. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.carj.2018.11.006\u003c/span\u003e\u003cspan address=\"10.1016/j.carj.2018.11.006\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePasquariello A, Innocenti M, Batini V, et al. Theoretical calculation of optimal depth in the percutaneous native kidney biopsy to drastically reduce bleeding complications and sample inadequacy for histopathological diagnosis. Nephrol Dial Transpl. 2007;22(12):3516\u0026ndash;20. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1093/ndt/gfm272\u003c/span\u003e\u003cspan address=\"10.1093/ndt/gfm272\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFerrer G, Andeen NK, Lockridge J, et al. Kidney biopsy adequacy: A metric-based study. Am J Surg Pathol. 2019;43(1):84\u0026ndash;92. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/PAS.0000000000001102\u003c/span\u003e\u003cspan address=\"10.1097/PAS.0000000000001102\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEmelianova D, Prikis M, Morris CS, et al. The evolution of performing a kidney biopsy: a single center experience comparing native and transplant kidney biopsies performed by interventional radiologists and nephrologists. BMC Nephrol. 2022;23(1):226. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1186/s12882-022-02860-1\u003c/span\u003e\u003cspan address=\"10.1186/s12882-022-02860-1\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePettit C, Kanagaratnam R, Coughlan F, Graf N, Hahn D, Durkan A. Kidney biopsy adequacy and complications in children \u0026mdash; does technique matter? Eur J Pediatr. 2022;181(7):2677\u0026ndash;84. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s00431-022-04464-1\u003c/span\u003e\u003cspan address=\"10.1007/s00431-022-04464-1\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eQian L, Menez S, Hu D, et al. Safety and Adequacy of Kidney Biopsy Procedure in Patients with Obesity. Kidney360. 2023;4(1):98. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.34067/KID.0006602022\u003c/span\u003e\u003cspan address=\"10.34067/KID.0006602022\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLuciano RL, Moeckel GW. Update on the Native Kidney Biopsy: Core Curriculum 2019. Am J Kidney Dis. 2019;73(3):404\u0026ndash;15. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1053/j.ajkd.2018.10.011\u003c/span\u003e\u003cspan address=\"10.1053/j.ajkd.2018.10.011\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWooldridge JT, Davis A, Fischer WG, Khalil MF, Zhang M, Afrouzian M. The Impact of Renal Tissue Procurement at Bedside on Specimen Adequacy and Best Practices. Am J Clin Pathol. 2019;151(2):205\u0026ndash;8. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1093/ajcp/aqy120\u003c/span\u003e\u003cspan address=\"10.1093/ajcp/aqy120\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAhangaran M, Sun E, Le K, et al. Pilot Study of a Web-Based Tool for Real-Time Adequacy Assessment of Kidney Biopsies. Kidney Int Rep. 2024;9(9):2809\u0026ndash;13. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.ekir.2024.06.019\u003c/span\u003e\u003cspan address=\"10.1016/j.ekir.2024.06.019\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEigbire-Molen OJ, Cassol CA, Kenan DJ, et al. Smartphone-based machine learning model for real-time assessment of medical kidney biopsy. J Pathol Inf. 2024;15:100385. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.jpi.2024.100385\u003c/span\u003e\u003cspan address=\"10.1016/j.jpi.2024.100385\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSingh G, Massak M, Czaplicki M, et al. Use of a Smartphone Camera at the Bedside to Assess Adequacy of Kidney Biopsies. J Am Soc Nephrol. 2021;32(12):3024\u0026ndash;6. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1681/ASN.2021070898\u003c/span\u003e\u003cspan address=\"10.1681/ASN.2021070898\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLeclerc S, Nadeau-Fredette AC, Elftouh N, Lafrance JP, Pichette V, Laurin LP. Use of Desmopressin Prior to Kidney Biopsy in Patients With High Bleeding Risk. Kidney Int Rep. 2020;5(8):1180\u0026ndash;7. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.ekir.2020.05.006\u003c/span\u003e\u003cspan address=\"10.1016/j.ekir.2020.05.006\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAthavale A, Kulkarni H, Arslan CD, Hart P. Desmopressin and bleeding risk after percutaneous kidney biopsy. BMC Nephrol. 2019;20:413. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1186/s12882-019-1595-4\u003c/span\u003e\u003cspan address=\"10.1186/s12882-019-1595-4\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-nephrology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bnep","sideBox":"Learn more about [BMC Nephrology](http://bmcnephrol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bnep/default.aspx","title":"BMC Nephrology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Kidney Biopsy, Biopsy complications, Biopsy adequacy, Quality improvement","lastPublishedDoi":"10.21203/rs.3.rs-9499410/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9499410/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eKidney biopsy is essential for diagnosis and management but carries bleeding risks. Efforts to reduce bleeding may compromise tissue adequacy, highlighting the need to systematically evaluate biopsy performance. Understanding factors that influence both safety and adequacy can guide targeted quality improvement (QI) efforts.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eWe conducted a retrospective single-center study of native kidney biopsies (2014\u0026ndash;2023) as part of a QI initiative to improve biopsy safety and adequacy. Multivariable logistic regression identified factors associated with major complications (need for angiography, embolization, or transfusion within seven days of biopsy) and biopsy adequacy (\u0026ge;\u0026thinsp;10 glomeruli for light microscopy and \u0026ge;\u0026thinsp;1 glomerulus for indirect immunofluorescence and electron microscopy).\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eA total of 796 biopsies were analyzed (56.2% female; median age 54.9 years; median BMI 28.9 kg/m\u0026sup2;). An 18-gauge needle was used in 98% of biopsies. Major complications occurred in 10.3%, improving from 14.5% in 2014 to 2.8% in 2023 following prior QI interventions. Biopsy adequacy was achieved in 58.4%. Higher hemoglobin (adjusted odds ratio (aOR) 0.73, 95% CI 0.60\u0026ndash;0.90) and platelet count (aOR 0.88, 95% CI 0.79-1.00) were associated with lower complications, whereas acute kidney injury (aOR 4.44 (95% CI 1.49\u0026ndash;13.24), elevated INR (aOR 2.72 (95% CI 1.03\u0026ndash;7.19) increased risk. Biopsy adequacy was higher with Radiologist #6 (aOR 2.59, 95% CI 1.47\u0026ndash;4.55) and #4 (aOR 2.24, 95% CI 1.07\u0026ndash;4.66), longer biopsy core length (aOR 2.13, 95% CI 1.53\u0026ndash;2.98), and lower BMI (aOR 0.97, 95% CI 0.94\u0026ndash;0.99).\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eThis study will inform the design of multidisciplinary QI interventions to improve kidney biopsy adequacy and further reduce the complication rate. Planned interventions include peer discussions led by proceduralists with the best adequacy outcomes and a high-risk biopsy protocol. Though center-specific, these results emphasize the value of local data in improving biopsy safety and establishing benchmarks for future guidelines.\u003c/p\u003e","manuscriptTitle":"Long-Term Evaluation of Kidney Biopsy Outcomes to Guide Continuous Quality Improvement","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-05-18 18:29:32","doi":"10.21203/rs.3.rs-9499410/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"74837092976426988333935300220365106424","date":"2026-05-22T16:33:33+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-19T16:21:34+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"242916689020991049736147635577239447111","date":"2026-05-12T21:37:47+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"88430552091753161167953043863850704084","date":"2026-05-10T16:42:20+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"51181963581874486764758715261961490912","date":"2026-05-07T11:45:46+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-05-07T10:50:26+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-04-25T06:01:54+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-04-24T08:13:20+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-04-24T08:12:28+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Nephrology","date":"2026-04-22T17:45:23+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-nephrology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bnep","sideBox":"Learn more about [BMC Nephrology](http://bmcnephrol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bnep/default.aspx","title":"BMC Nephrology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"62916881-b38e-4526-af45-59199a146989","owner":[],"postedDate":"May 18th, 2026","published":true,"recentEditorialEvents":[{"type":"reviewerAgreed","content":"74837092976426988333935300220365106424","date":"2026-05-22T16:33:33+00:00","index":124,"fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-19T16:21:34+00:00","index":82,"fulltext":""},{"type":"reviewerAgreed","content":"242916689020991049736147635577239447111","date":"2026-05-12T21:37:47+00:00","index":81,"fulltext":""},{"type":"reviewerAgreed","content":"88430552091753161167953043863850704084","date":"2026-05-10T16:42:20+00:00","index":77,"fulltext":""},{"type":"reviewerAgreed","content":"51181963581874486764758715261961490912","date":"2026-05-07T11:45:46+00:00","index":69,"fulltext":""},{"type":"reviewersInvited","content":"83","date":"2026-05-07T10:50:26+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-18T18:29:32+00:00","versionOfRecord":[],"versionCreatedAt":"2026-05-18 18:29:32","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9499410","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9499410","identity":"rs-9499410","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}