Risk factors analysis of Flexible Ureteroscopic Lithotripsy with UTI and construction of clinical prediction model

Risk factors analysis of Flexible Ureteroscopic Lithotripsy with UTI and construction of clinical prediction model | 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 Risk factors analysis of Flexible Ureteroscopic Lithotripsy with UTI and construction of clinical prediction model Feng Xiong, Pan Zhang, Xiangyi Fan, Hongliang Qiao, Zhongjun Cao, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4183532/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Purpose The flexible ureteroscope offers advantages such as safety, minimally invasive procedures, quick recovery, and a high rate of stone removal. It has become a standard method for treating ureteral stones as well as small and medium-sized kidney stones. UTI is one of the most common postoperative complications that can lead to sepsis, systemic inflammatory response syndrome, urological sepsis, and even septic shock. Our aim is to analyze the risk factors for UTI following ureteroscopic lithotripsy and to develop corresponding clinical prediction models. Methods A retrospective analysis was conducted on patients who underwent FURS surgery for urinary tract stones at our hospital from January 2021 to January 2023. Univariate and multivariate logistic regression analyses were used to identify independent risk factors for postoperative infection and to develop the corresponding Nomogram prediction model. Results In total, 560 patients underwent flexible ureteroscopic lithotripsy (FURL) in our hospital, including 111 patients who developed postoperative UTI, resulting in an incidence rate of 19.8%. Analysis of the multivariate logistic regression data showed that renal dysfunction[OR = 2.103(95%CI:1.134–3.907),P = 0.018],positive preoperative urine culture [OR = 6.070(95%CI:1.800-20.474),P = 0.004], positive urinary nitrate [OR = 3.206 (95%CI: 1.599–6.429),P = 0.001],IL-6 > 5.3pg/ml[OR = 6.876(95%CI:3.734–12.661),P 430 umol /L [OR = 2.024(95%CI:1.088–3.765),P = 0.026], ureteral stricture[OR = 3.174(95%CI:1.660–6.070), P < 0.001] were independent risk factors for UTI in patients after flexible ureteroscopy. The area under the ROC curve of the constructed nomogram prediction model is 0.89 (95% CI: 0.876–0.937). The concordance index reached 0.841. Conclusion Renal dysfunction, positive preoperative urine culture, positive urine nitrite, IL-6 > 5.3 pg/ml, uric acid > 430 umol/L, and ureteral stenosis were identified as risk factors for UTI after flexible ureteroscopic lithotripsy. The nomogram prediction model has high clinical value in the prediction of UTI. Flexible ureteroscope Urinary tract infection Fever Predictive model Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Urinary calculi are common diseases in the urinary tract, with an incidence of up to 59% in Europe and about 15% in Asia [ 1 ] . The treatments for urinary stones include conservative treatment, ureterolithotomy, Extracorporeal Shock Wave Lithotripsy (ESWL), percutaneous nephrolithotomy (PCNL), and ureteroscopic lithotomy (URL). Flexible Ureteroscopic Lithotripsy (FURL) has the advantages of being slender, soft, and flexible, allowing it to leverage its unique benefits in treating specific cases of kidney stones, such as calyceal diverticulum, horseshoe kidney stones, ectopic kidney stones, polycystic kidney stones, isolated kidney stones, and other complex stones. It can ensure a high rate of stone clearance without leading to serious postoperative complications [ 2 ] . Various complications can occur after FURL, and the overall complication rate is about 9% – 25% [ 3 ] . Urinary tract infection (UTI), ureteral injury, hematuria, and postoperative renal colic are common complications of FURL. UTI is one of the most common postoperative complications, causing systemic inflammatory response syndrome (SIRS), urogenic sepsis, and even septic shock [ 4 ] . The postoperative fever rate is about 26%, the probability of sepsis is about 2%~8%, and the mortality rate is about 20%~42%, which seriously harms the economy and life safety of the patient [ 5 , 6 ] .Although the fever rate after FURL and ESWL was significantly lower than after PCNL, infections were still inevitable. Currently, there are numerous and diverse risk factors associated with postoperative febrile urinary tract infections in FURL [ 7 , 8 ] . Ureteroscopy surgery continues to be a hot and challenging topic in the research field. Differences in case numbers, inclusion criteria, statistical methods, and other factors in previous studies have resulted in varying conclusions [ 9 , 10 ] , necessitating additional research and investigation. Materials and methods Patients We retrospectively identified the data of patients with renal stones who received FURL in our hospital, a tertiary hospital with the highest level of referral directly under National Healthy Committee of China, from January 2021 to January 2023. The study was approved by the Institutional Ethics Committee of the First Clinical Medical College of the China Three Gorges University. Inclusion and exclusion criteria Inclusion criteria: (1) There is imaging data confirming the presence of urinary calculi, along with clear indications for surgery; (2) UTI following flexible ureteral lithotripsy; excluding infections from other systems.(3) Hospital stay > 3 days; (4) The clinical data are complete, accurate, and available. Exclusion criteria: (1) Accompanied by heart, liver, spleen, lung, kidney and other important organ failure; (2) Combined with autoimmune system and hematological system diseases; (3)The hospitalization data are incomplete, and the examinations are not perfect; (4) Serious complications or complications during the treatment process require other treatment. Diagnostic Standard Urinary tract infections: patient symptoms (lower urinary tract infection: frequent urination, urgent urination, urination pain, hematuria, and lumbosacral pain; upper urinary tract infections: fever, low back pain, nausea, vomiting, and other systemic symptoms), medical history (urinary surgery, history of diabetes, history of related drug use, etc.), and signs (fever, back pain, rib and ridge horn tenderness or percussion pain, etc.), one or more suggest a urinary tract infection. Having any one of the following three conditions: body temperature > 38.5°C, positive urine culture, and positive blood culture. Additionally, exclude other factors and infections induced by the system. Clinical data collection All patient information is obtained from the inpatient medical record system, imaging system, and surgical anesthesia system. We collected and analyzed the following factors: (1) General information: Age, Gender, BMI, ASA, basic diseases (such as hypertension, diabetes, renal insufficiency), previous history of stone surgery, hydronephrosis, preoperative infection history, preoperative antibiotic use time, and retention time of urinary catheter; (2) Laboratory indicators: blood routine, blood biochemistry, blood uric acid, urine routine (urine protein, urine occult blood, urine nitrite, urine white blood cells), preoperative urine culture, coagulation function, cytokines (IL-6, TNF-α); (3) Surgical information: surgical time, bleeding volume, perfusion volume, ureteral stent placement, nephrostomy tube placement, ureteral stenosis; (4) Imaging data: Abdominal plain film (KUB), color ultrasonography, excretory urography (IVU), non-contrast computed tomography (CT), characteristics of stones (single or multiple, size, location, side), maximum diameter of stones, CT value of stones, stone components (infectious stones, calcium stones, cystine stones, uric acid stones, etc). Surgical methods For patients with positive preoperative urine culture, sensitive antibiotics should be used based on drug sensitivity results, and surgery should be performed after the urine culture results turn negative. All patients received prophylactic use of antibiotics (cephalosporin) at 30 points before surgery. If the patient's urine culture was positive before surgery, they were replaced with sensitive antibiotics. After the induction of general anesthesia in the lithotomy position, F8/9.8 ureteroscope (Wolf, Germany) was inserted into the bladder to explore the ureter on the affected side. A zebra-guide wire was inserted from the ureteral orifice to the renal pelvis. F12/14or F14/16 ureteral access sheath (based on gender and ureteral condition) was inserted into the upper ureter near the junction of the renal pelvis. Subsequently, the guidewire was removed, and the flexible ureteroscope (Olympus, Japan) was advanced through the ureteral access sheath into the renal collecting system. Stones were then located and fragmented using a holmium laser. Finally, an F5/6 ureteral stent was inserted, and the operation was completed. Statistical Analysis SPSS(22.0) and R(4.2.1) software were used for statistical analysis. Normally distributed continuous variables were presented as mean ± standard deviation (x ± s), while non-normally distributed continuous variables were presented as median. The comparison between groups was conducted using t-tests or Mann-Whitney U tests. Categorical variables were analyzed using the χ2 test or Fisher's exact test and presented as numbers (n) and percentages (%). Univariate and multivariate logistic regression models were conducted to ascertain the independent effect of risk factors for postoperative UTI following FURL. Variables showing a P value < 0.05 in univariable analysis were considered as candidates for the multivariable model. Receiver Operating Characteristic curve (ROC), concordance index (c-index), and calibration curves were performed to assess the accuracy of the prediction model. Decision Curve Analysis (DCA) was used to calculate the net benefit threshold for clinical interventions. Results Univariate Analysis Results According to the inclusion and exclusion criteria, a total of 560 patients were enrolled, including 386 males (69%) and 174 females (31%), with an average age (51.03 ± 13.67) years and an average BMI (24.43 ± 3.19) kg/m. 2 Of these, 111 patients developed UTI after FUTL, The postoperative infection rate was 19.8%. The basic characteristics of these patients were summarized in Table 1 . Univariate analysis of the risk factors showed that UTI was associated with renal insufficiency (χ2 = 38.959, P < 0.001), Preoperative UTI (χ2 = 35.797, P < 0.001), Preoperative ureteral stent placement (χ2 = 30.174, P < 0.001), Ureteral stenosis (χ2 = 12.050, P = 0.001), Preoperative antibiotic use duration (Z = 3.637, P = 0.003), IL-6(χ2 = 98.112, P < 0.001), Uric acid (χ2 = 13.643, P < 0.001), Preoperative urine culture (χ2 = 50.578, P < 0.001), Urinary nitrite (χ2 = 70.835, P < 0.001), Urinary leukocytes (χ2 = 7.996, P = 0.005), History of stone surgery(χ2 = 19.207,P < 0.001), Stone diameter (Z=-4.343, P < 0.001), Operative duration (Z=-3.442,P = 0.001), Irrigation volume(Z=-3.567, P < 0.001), Stone composition (χ2 = 81.826, P < 0.001). Table 1 Risk factors for urinary tract infections after FURL Risk factor UTI(n = 111) Non-UTI(n = 449) t/Z/χ2 P value Age (mean ± SD), years 51.97 ± 13.58 50.80 ± 13.69 -0.813 0.417 BMI (mean ± SD), kg/m 2 24.33 ± 2.88 24.45 ± 3.27 0.374 0.709 Gender, n(%) Male female 73(65.77) 38(34.23) 313(69.7) 136(30.3) 0.647 0.421 ASA-PS, n(%) 1 2 3 4 3(2.70) 76(68.47) 30(27.03) 2(1.80) 9(2) 328(73) 108(24.1) 4(0.9) -0.727 0.467 Hypertension, n(%) Yes no 36(32.43) 75(67.57) 125(27.8) 324(72.2) 0.916 0.338 Diabetes, n(%) Yes No 14(12.61) 97(87.39) 59(13.14) 390(86.86) 0.022 0.882 Renal dysfunction, n(%) Yes No 69(62.16) 42(37.84) 136(30.29) 313(69.71) 38.959 <0.001 * Hydronephrosis, n(%) Yes No 70(63.06) 41(36.94) 238(53.01) 211(46.99) 3.637 0.057 Preoperative UTI, n(%) Yes No 30(27.03) 81(72.97) 32(7.13) 417(92.87) 35.797 <0.001 * Preoperative ureteral stenting, n(%) Yes No 26(23.42) 85(76.58) 28(6.24) 421(96.76) 30.174 5.3 33(29.73) 78(70.27) 352(78.40) 97(21.60) 98.112 4.6 65(58.56) 46(41.44) 304(67.71) 145(32.29) 3.314 0.069 creatinine(umol/L), n(%) 133 3(2.70) 81(72.97) 27(24.32) 4(0.89) 368(81.96) 77(17.15) 5.137 0.077 urea nitrogen(mmol/L), n(%) 9.5 9(8.11) 80(72.07) 22(19.82) 27(6.01) 363(80.85) 59(13.14) 4.219 0.121 albumin(g/L), n(%) 430 64(57.66) 47(42.34) 338(75.28) 111(24.72) 13.643 <0.001 * Preoperative urine culture, n(%) Negative Positive 87(78.38) 24(21.62) 436(97.10) 13(2.90) 50.578 <0.001 * urinary protein, n(%) Negative Positive 65(58.56) 46(41.44) 300(66.82) 149(33.18) 2.673 0.102 urinary occult blood, n(%) Negative Positive 36(32.43) 75(67.57) 179(39.87) 270(60.13) 2.079 0.149 Urinary leukocyte, n(%) Negative Positive 49(44.14) 62(55.86) 265(59.02) 184(40.98) 7.996 0.005 * Urinary nitrite, n(%) Negative Positive 64(57.66) 47(42.34) 406(90.42) 43(9.58) 70.835 <0.001 * History of stone surgery, n(%) No Yes 70(63.06) 41(36.94) 369(82.18) 80(17.82) 19.207 <0.001 * Stone location, n(%) Ureter Renal pelvis Multiple stone 38(34.23) 59(53.15) 14(12.61) 191(42.54) 185(41.20) 73(16.26) 5.180 0.075 Number of stones, n(%) Single Multiple 71(63.96) 40(36.04) 327(72.83) 122(27.17) 3.402 0.065 Stone laterality,n(%) Unilateral Bilateral 96(86.49) 15(13.51) 411(91.54) 38(8.46) 2.649 0.104 Stone diameter(mm) 0.9(0.7, 1.0) 0.7(0.6, 0.9) -4.343 <0.001 * CT value (HU) 618(489, 819) 715(516, 876) -1.319 0.187 Operative duration (min) 85(60, 120) 70(55, 95) -3.422 0.001 * Blood loss (ml) 10(5, 20) 5(5, 10) -1.706 0.088 Irrigation volume (ml) 960(690, 1225) 790(655, 1048) -3.567 <0.001 * Catheter placement period (D) 2(1, 3) 2(1, 3) -0.71 0.481 Preoperative antibiotic usage time (D) 1(0, 4) 0(0, 3) -2.948 0.003 * Stone components, n(%) Infectious stones Calcium stones Cysteine stones Uric acid stones 43(38.74) 46(41.44) 3(2.70) 19(17.12) 32(7.13) 372(82.85) 11(2.45) 34(7.57) 81.826 <0.001 * *P<0.05 BMI :body mass index; ASA-PS :American Society of Anesthesiologists physical status classification system; IL-6 :Interleukin-6; TNF-α :Tumor Necrosis Factor-α Univariate and Multivariate Logistic Regression Analysis Results In the univariate analysis, significant differences were observed between groups with UTI and non-UTI in terms of renal dysfunction, preoperative UTI, preoperative ureteral stent placement, positive preoperative urine culture, positive urinary leukocyte, positive urine nitrite, IL-6 > 5.3 pg/ml, uric acid > 430 umol/L, history of stone surgery, irrigation volume, ureteral stenosis, stone diameter, preoperative antibiotic use duration, and operative duration. In the multivariate analysis, renal dysfunction [OR = 2.103 (95% CI: 1.134, 3.907), P = 0.018], preoperative urine culture [OR = 6.070 (95% CI: 1.800, 20.474), P = 0.004], positive urine nitrite [OR = 3.206 (95% CI: 1.599, 6.429), P = 0.001], IL-6 > 5.3 pg/ml [OR = 6.876 (95% CI: 3.734, 12.661), P 430 umol/L [OR = 2.024 (95% CI: 1.088, 3.765), P = 0.026], and Ureteral stenosis [OR = 3.174 (95% CI: 1.660, 6.070), P < 0.001] were independently associated with UTI(Table 2 ). Table 2 Univariate and multivariate logistic regression analysis of risk factors for UTI Risk factor Univariate logistics Multivariate logistics OR(95%CI) P value OR(95%CI) P value Renal dysfunction 3.781(2.452–5.831) <0.001 * 2.103(1.134–3.901) 0.003 * Preoperative UTI 4.826(2.779–8.382) <0.001 * 2.071(0.827–5.185) 0.120 Preoperative ureteral stenting 4.599(2.569–8.235) <0.001 * 1.481(0.585–3.749) 0.407 Positive Preoperative urine culture 9.252(4.535–18.877) <0.001 * 6.070(1.800-20.474) 0.004 * Positive Urinary leukocyte 1.822(1.198–2.771) 0.005 * 0.806(0.438–1.483) 0.488 Posotive Urinary nitrite 6.934(4.246–11.324) 5.3 pg/ml 8.577(5.388–13.654) <0.001 * 6.876(3.734–12.661) 430 umol/L 2.236(1.450–3.449) <0.001 * 2.024(1.088–3.765) 0.026 * History of stone surgery 2.702(1.714–4.258) <0.001 * 1.440(0.740–2.804) 0.283 Irrigation volume 1.001(1.001–1.002) <0.001 * 1.002(0.999–1.004) 0.280 Ureteral stricture 2.183(1.396–3.413) 0.001 * 3.174(1.660–6.070) <0.001 * Stone diameter 3.211(1.581–6.522) 0.001 * 2.336(0.764–7.144) 0.137 Preoperative antibiotic usage time 1.091(1.026–1.161) 0.006 * 0.895(0.799–1.002) 0.054 Operative duration 1.009(1.003–1.014) 0.001 * 0.993(0.972–1.015) 0.545 *P<0.05 CI :confidence interval Establishment and Evaluation of Nomogram model Based on the results of the Multivariate Logistic Regression Analysis, visualize each independent risk factor in the nomogram model(Fig. 1 ). The influence of each independent risk factor on the occurrence of postoperative urinary tract infection is presented in segmented values. The sum of the scores in the nomogram model indicates the likelihood of UTI. The results of ROC curve analysis showed the area under the curve (AUC) for each independent risk factor and the Nomogram prediction model(Fig. 2 ).The AUC of the nomogram prediction model was 0.90 (95% CI: 0.876–0.937). The calibration curve of the prediction model is shown in Fig. 3 . A Validation of the nomogram model was performed using a 1000-bootstrap analysis. the calculated C-index = 0.834, P = 0.301,which showed good fitting of the nomogram model.The DCA curve for the predictive nomogram is presented in Fig. 3 . B , demonstrating significant net benefits of the predictive nomogram. When the event incidence ranges from 1–70%, the application of the prediction model may yield a net benefit in clinical intervention. However, when the incidence exceeds the 70% threshold, the prediction model does not provide significant benefits. Overall, the predictive nomogram model showed a strong correlation with the actual observed values, indicating its relative accuracy and consistency. Comparative analysis of positive pathogenic bacteria in urine cultures In this study, the bacterial distribution of urine cultures in the UTI group and non-UTI group is illustrated in Fig. 4 . Among the 560 patients enrolled, a total of 37 cases had a positive urine culture, resulting in a positive urinary culture rate of 6.6%. Specifically, 24 (21.6%) out of 111 patients in the UTI group and 13 (2.9%) out of 449 patients in the non-UTI group. The positive rate of urine culture in the UTI group was higher than that in the non-UTI group. Most of the pathogenic bacteria in the two groups were gram-negative bacteria, mainly E. coli (54.1%), followed by Klebsiella pneumoniae (10.8%).The main Gram-positive bacteria were Enterococcus faecalis (10.8%). There are research reports indicating that selecting medication based on preoperative urine culture results is sometimes unreliable, as the bacterial findings of preoperative urine culture and stone bacterial culture do not always align. In a single-center retrospective study conducted by Paonessa[ [ 11 ] ], 352 (45.4%) out of 776 cases tested positive for urine culture, and 300 (38.7%) were positive for stone culture.Among patients who tested positive for both cultures, 103 (13.3%) had differences in the pathogens. The cultured bacteria were mainly Staphylococcus, followed by E-coli. 13.7% of the patients with positive stone cultures were Enterococcus faecalis, which is not covered by common cephalosporins and is also resistant to fluoroquinolones commonly used in the urinary system. Inappropriate antimicrobial treatment may delay recovery, leading to worsening of the infection. In an international, multicenter study[ [ 12 ] ], 865 out of 5803 patients who underwent PCNL had positive urine cultures (16.2%), with Escherichia coli being the main pathogen. Compared to other continents, patients in the Americas had the lowest proportion of Escherichia coli in urine cultures (20.9%), with Gram-positive bacteria being the dominant strain. This study's findings are akin to those of Paonessa and our own research. One current limitation is that our hospital has not conducted intraoperative stone culture on patients undergoing stone surgery. Additionally, the sample size of positive urine cultures is too small to verify the consistency between preoperative urine culture and stone culture results. Therefore, establishing a bacterial spectrum through urine culture and stone culture is an important step in prescribing preventive antibiotics and treating urinary tract infections. Discussion Urinary calculi are common diseases of the urinary system, especially upper urinary tract calculi, with an incidence of about 25% [ 13 ] . It can cause urinary tract obstruction, kidney damage, and even renal failure [ 14 , 15 ] . Stones can be treated with open lithotomy, PCNL, ESWL, and URL. Open lithotomy requires the patient's surgical tolerance and body shape. An underweight or overweight body can complicate the surgery, lead to significant surgical trauma, and negatively impact the patient's prognosis. Postoperative bleeding and tissue adhesion in the surgical area can lead to challenges in subsequent stone removal, a procedure that is currently less frequently employed in clinical practice. ESWL is only appropriate for small stones and is not recommended for patients with large stones, infections, or ureteral strictures. PCNL is suitable for kidney stones and stones at the junction of the ureter, but not for middle and lower ureteral stones. As an invasive procedure, surgery is challenging, significantly impacting the patient and carrying a high risk of bleeding. With advancements in medical equipment and laser technology, URS has gradually emerged as the "gold standard" for treating upper ureteral and kidney stones due to its safety and minimally invasive nature [ 16 , 17 ] . A total of 560 patients were enrolled in this study, with 111 in the UTI group and 449 in the non-UTI group. Excluding postoperative infection and other systemic infections, the rate of postoperative urinary tract infection was approximately 19.8%, which is similar to the rate reported by Yamashita (20%). Univariate analysis revealed that the UTI group had larger values than the non-infected group in terms of intraoperative perfusion amount, stone diameter, preoperative antibiotic use time, and operation time (P 5.3 pg/ml, blood uric acid > 430 umol/L, and ureteral stenosis were independent risk factors for UTI after FURL. At present, the predictive value of a positive preoperative urine culture (UC) for UTI after FURL is still controversial. Some studies have considered preoperative urine culture to be of predictive value [ 18 , 19 ] , while others have reported that preoperative urine cultures are not accurate enough to have predictive value due to stone-induced urinary obstruction [ 20 ] . Most stones contain a large amount of colonized bacteria and endotoxins. Preoperative stone entrapment and polyp wrapping can cause partial or complete obstruction of the urinary system, leading to hydronephrosis and ureteral fluid accumulation, which creates an environment favorable for bacterial growth. Urine carrying bacteria cannot flow down to the bladder due to urinary tract obstruction, resulting in negative urine culture results.Therefore, the UC cannot accurately reflect the microbial status of upper urinary tract urine. In addition, a large amount of physiological saline is required for high-pressure infusion during ureteroscopic lithotripsy to maintain a clear field of view during the operation. As the perfusion pressure increases, the perfusion fluid can reflux through various channels such as renal pelvic veins, renal tubules, and lymph nodes. This can cause bacteria and endotoxins in the stones to reflux into the bloodstream, leading to sepsis and even septic shock. In our study, a positive preoperative urine culture not only refers to a positive result from the last preoperative urine culture but also to at least one occurrence of a positive urine culture result among several preoperative urine culture results from the patient's admission to surgery.Urinary tract obstruction and prolonged use of antibiotics can lead to false negative results in preoperative urine culture in patients. The study by Chen, Kreydin, and others also reported that a negative preoperative urine culture is not sufficient to rule out the risk of postoperative urinary tract infections [ 19 , 21 ] . For patients with positive urine culture results, we will choose appropriate antibiotics for treatment according to the sensitivity of the culture results. Surgery will be performed after the urine culture results turn negative. Singh's research suggests that renal pelvis puncture urine culture can better predict Systemic Inflammatory Response Syndrome (SIRS) than standard urine culture [ 22 ] . However, using intraoperative puncture urine culture to predict postoperative infections has limited early predictive value due to the long cultivation time, and it lacks high clinical practicality. Some studies have found a rapid and convenient non-molecular diagnostic method: urinary nitrite. When gram-negative bacteria infect the body, bacteria containing reductase can convert nitrate in urine into nitrite. Positive urine nitrite often indicates a bacterial infection, with high specificity (98%) but low sensitivity (only 23–43%) [ 20 ] . Some bacteria do not contain nitrate reductase, which is a limitation of this method. When infected with this type of bacteria, the urine nitrite test result will be negative. Although there are limitations, urinary nitrite is also widely used as an indirect indicator for diagnosing bacterial urine. According to the nomogram prediction chart model, the scores for a positive urine culture and positive urine nitrite before the operation were 86 and 77 points, respectively. These scores are highly valuable in predicting postoperative urinary tract infections. BMI is a key indicator used in clinics to determine whether patients are obese or not. With the increase in BMI, the prevalence of cardiovascular and cerebrovascular diseases, diabetes, and other risk factors will also increase. As fat accumulates in obese patients, the plasma osmolality increases, disrupting the dynamic balance of the internal environment and leading to a decrease in immune cell function [ 23 ] . A study has found that BMI ≥ 25 or higher is an independent risk factor for systemic inflammatory response syndrome after PCNL [ 4 ] . Another study found that a low BMI was also an important risk factor for UTI after surgeries[ [ 24 ] ]. However, the number of positive samples is only 3, so more studies with larger samples are needed to verify it.Some studies suggest that diabetic patients with poor glycemic control have a higher risk of urinary tract infection (UTI) following surgery [ 25 ] . The long-term high glucose state in diabetic patients can lead to tissue circulation disorders, followed by tissue ischemia and hypoxia, which can increase the risk of tissue necrosis. Additionally, during hyperglycemia, the body's ability for leukocyte movement and phagocytosis decreases, leading to a decline in immune function [ 26 , 27 ] . Our study showed that BMI and diabetes were not independent risk factors for UTI after furs, which may be attributed to regional patient factors.For patients with pre-operative hyperglycemia, we will regulate blood glucose levels to normal before surgery to reduce the postoperative infection rate. For patients with diabetes mellitus, the current consensus both domestically and internationally is that maintaining good preoperative blood glucose control will significantly reduce the likelihood of postoperative infections. Interleukin-6 (IL-6) is a cytokine with multiple biological activities, participating in systemic infections, autoimmune diseases, and the development of malignant tumors through immune regulation [ 28 ] . QI found that compared to procalcitonin (PCT), IL-6 at 2 hours postoperatively is the earliest and most valuable inflammatory marker for diagnosing postoperative urosepsis after percutaneous nephrolithotomy (PCNL) [ 29 ] . Unfortunately, their study did not provide the optimal critical value for IL-6 at 2 hours postoperatively to further guide clinical treatment. Jia [ 30 ] evaluated the diagnostic value of serum concentrations of CRP, PCT, and IL-6, and assessed whether their combined application is superior to individual use in diagnosing postoperative infections. The area under the curve (AUC) for CRP, PCT, and IL-6 in bacterial infections were 0.791, 0.859, and 0.783, respectively. The combination of CRP + PCT + IL-6 significantly improved the diagnostic efficiency of bacterial infections, with an AUC of 0.881. PCT, CRP, or IL-6 as single indicators have limited diagnostic value for predicting postoperative urinary tract infections (UTI) after flexible ureteroscopy (FURS), compared to the combined use of the three indicators. It is worth noting that these inflammatory markers are currently mainly used in the study of systemic inflammatory response syndrome (SIRS) after PCNL, and their effectiveness in early prediction of UTI after FURS needs further validation. Additionally, the critical values for each inflammatory marker vary slightly in different studies, which slightly limits their application in clinical practice. Therefore, future research is still needed to determine the optimal critical values for these inflammatory markers in different settings. In our study, renal dysfunction and ureteral stenosis are independent risk factors for UTI after surgery. When renal dysfunction occurs, the local and systemic defense mechanisms of patients change. The attachment of uropathogenic microorganisms to urothelial cells and the absorption of bacterial toxins into the blood initiate a complex process in the host. The release of various cytokines and mediator molecules, along with the activity of immune regulatory cells, influences the interstitial reaction of the upper and lower urinary tract and kidney. This leads to a decrease in body immunity and an increased risk of bacterial infection. Acute infection can affect the progression of preexisting renal disease. In cases of renal parenchymal damage or anatomical changes in the urinary tract, along with a deficiency in secretory IgA, Tamm-Horsfall glycoprotein, or other defense factors that protect the body's defense mechanism, renal function failure can be further exacerbated [ 31 ] . Ureteral stricture is a frequent complication of ureteral calculi, which can result from laser thermal injury to the mucosal wall, stone entrapment, polyp encasement, and other strictures that may occur during ureteral surgery. Its further development may lead to renal and ureteral obstruction, renal function injury, and even renal failure. Hydronephrosis in the kidney and ureter leads to an increase in intrarenal pressure, causing bacteria attached to the urine and stone surfaces to be absorbed into the blood [ 32 ] . The wrapping of polyps also diminishes the effectiveness of ESWL,FURL, and other procedures. The stones cannot be be broken, the remaining stones are trapped, and the urine containing bacteria cannot be drained smoothly, leading to further exacerbation of the infection. Our study also has some limitations. The main limitations are the single-center, retrospective study and the relatively limited number of patients. The influencing factors of this study mainly involve the general clinical data and intraoperative conditions of patients, while ignoring some different intraoperative iatrogenic factors, such as the anesthesia mode of surgery, operating room temperature, intravenous infusion, and intraoperative infusion fluid absorption leading to the temperature change of patients, and the exposure of general anesthesia intubation. Additionally, the single-center data source of this study also has a certain impact on the reliability of the prediction model, and more validation data need to be obtained from other medical institutions. Therefore, more multicenter, large-sample prospective controlled studies are needed to verify the predictive validity and practicality of nomograms. Conclusion Renal dysfunction, positive preoperative urine culture, positive urine nitrite, IL-6 > 5.3 pg/ml, uric acid > 430 umol/l, and ureteral stenosis were identified as independent risk factors for UTI after FURL. The c-index and AUC of the nomogram prediction model constructed demonstrate that the prediction model exhibits good discrimination and accuracy. DCA shows that when the threshold is below 70%, this prediction model may provide net benefits for clinical intervention. Declarations Acknowledgements The author wish to thank the First Clinical Medical College of Three Gorges University and the Institute of Urology for their valuable assistance in this study Statement of Ethics The study was approved by the Institutional Ethics Committee of the First Clinical Medical College of the China Three Gorges University. all patient information was obtained from the hospitalization system, All participants gave written informed consent before participating. Conflict of Interest Statement The authors declare that they have no competing interests. Funding Sources No funding was received for this study Author Contributions F.X. and X.C: contributed to the research ideas and design for study; F.X and Z.C.: Collected patient data and conducted analysis and organization; F.X, X.F and P.Z: Data analysis and model construction; F.X and H.Q: wrote and revised manuscript; X.C.: supervision or mentorship of manuscripts. References Liu, Y,Chen, Y,Liao, B,Luo, D,Wang, K,Li, H, et al.(2018) Epidemiology of urolithiasis in Asia. Asian J Urol 5 (4), https://doi.org/10.1016/j.ajur.2018.08.007. Wollin, D A,Joyce, A D,Gupta, M,Wong, M Y C,Laguna, P,Gravas, S, et al.(2017) Antibiotic use and the prevention and management of infectious complications in stone disease. World J Urol 35 (9), https://doi.org/10.1007/s00345-017-2005-9. Volkin, D.Shah, O.(2016) Complications of ureteroscopy for stone disease. Minerva Urol Nefrol 68 (6). Chugh, S,Pietropaolo, A,Montanari, E,Sarica, K.Somani, B K, (2020) Predictors of Urinary Infections and Urosepsis After Ureteroscopy for Stone Disease: a Systematic Review from EAU Section of Urolithiasis (EULIS). Curr Urol Rep 21 (4), https:// doi.org/10.1007/s11934-020-0969-2. Peng, C,Li, J,Xu, G,Jin, J,Chen, J.Pan, S. (2021) Significance of preoperative systemic immune-inflammation (SII) in predicting postoperative systemic inflammatory response syndrome after percutaneous nephrolithotomy. Urolithiasis 49 (6), https://doi.org/10.1007/s00240-021-01266-2. Kriplani, A,Pandit, S,Chawla, A,de la Rosette, J,Laguna, P,Jayadeva Reddy, S, et al., (2022) Neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) and lymphocyte-monocyte ratio (LMR) in predicting systemic inflammatory response syndrome (SIRS) and sepsis after percutaneous nephrolithotomy (PNL). Urolithiasis 50 (3), https://doi.org/10.1007/s00240-022-01319-0. Liu, M,Zhu, Z,Cui, Y,Zeng, H,Li, Y,Huang, F, et al.(2022) Correction to: The value of procalcitonin for predicting urosepsis after mini-percutaneous nephrolithotomy or flexible ureteroscopy based on different organisms. World J Urol 40 (2), https://doi.org/10.1007/s00345-021-03869-1. Wang, S,Yuan, P,Peng, E,Xia, D,Xu, H,Wang, S, et al.(2020) Risk Factors for Urosepsis after Minimally Invasive Percutaneous Nephrolithotomy in Patients with Preoperative Urinary Tract Infection. Biomed Res Int 2020 , https:// doi.org/10.1155/2020/1354672. Ma, Y C,Jian, Z Y,Li, H.Wang, K J. (2021) Preoperative urine nitrite versus urine culture for predicting postoperative fever following flexible ureteroscopic lithotripsy: a propensity score matching analysis. World J Urol 39 (3), https://doi.org/10.1007/s00345-020-03240-w. Tan, D,Wu, F.Huo, W. (2022) Clinical Characteristics and Risk Factors of Systemic Inflammatory Response Syndrome after Flexible Ureteroscopic Lithotripsy. Arch Esp Urol 75 (7), https://doi.org/10.56434/j.arch.esp.urol.20227507.89. Paonessa, J E,Gnessin, E,Bhojani, N,Williams, J C, Jr..Lingeman, J E (2016) Preoperative Bladder Urine Culture as a Predictor of Intraoperative Stone Culture Results: Clinical Implications and Relationship to Stone Composition. J Urol 196 (3), https://doi.org/10.1016/j.juro.2016.03.148. Gutierrez, J,Smith, A,Geavlete, P,Shah, H,Kural, A R,de Sio, M, et al.(2013) Urinary tract infections and post-operative fever in percutaneous nephrolithotomy. World J Urol 31 (5), https://doi.org/10.1007/s00345-012-0836-y. Huang, H,Li, M,Fan, H.Bai, R, (2021) Temporal Trend of Urolithiasis Incidence in China: An Age-Period-Cohort Analysis. Int J Gen Med 14 , https://doi.org/10.2147/IJGM.S313395. Ziemba, J B.Matlaga, B R, (2017) Epidemiology and economics of nephrolithiasis. Investig Clin Urol 58 (5), https://doi.org/10.4111/icu.2017.58.5.299. Thongprayoon, C,Krambeck, A E.Rule, A D. (2020) Determining the true burden of kidney stone disease. Nat Rev Nephrol 16 (12), https://doi.org/10.1038/s41581-020-0320-7. Mi, Q,Meng, X,Meng, L,Chen, D.Fang, S.(2020) Risk Factors for Systemic Inflammatory Response Syndrome Induced by Flexible Ureteroscope Combined with Holmium Laser Lithotripsy. Biomed Res Int 2020 , https://doi.org/10.1155/2020/6842479. Friedlander, D F,Brant, A,McClure, T D,Del Pizzo, J,Nowels, M A,Trinh, Q D, et al.(2021) Real-world comparative effectiveness of shockwave lithotripsy versus ureterorenoscopy for the treatment of urinary stones. World J Urol 39 (6), https://doi.org/10.1007/s00345-020-03430-6. Gao, X,Lu, C,Xie, F,Li, L,Liu, M,Fang, Z, et al.(2020) Risk factors for sepsis in patients with struvite stones following percutaneous nephrolithotomy. World J Urol 38 (1), https://doi.org/10.1007/s00345-019-02748-0. Chen, D,Jiang, C,Liang, X,Zhong, F,Huang, J,Lin, Y, et al.(2019) Early and rapid prediction of postoperative infections following percutaneous nephrolithotomy in patients with complex kidney stones. BJU Int 123 (6), https://doi.org/10.1111/bju.14484. Zhu, Z,Cui, Y,Zeng, H,Li, Y,Zeng, F,Li, Y, et al.(2020) The evaluation of early predictive factors for urosepsis in patients with negative preoperative urine culture following mini-percutaneous nephrolithotomy. World J Urol 38 (10), https://doi.org/10.1007/s00345-019-03050-9. Fan, J,Wan, S,Liu, L,Zhao, Z,Mai, Z,Chen, D, et al.(2017) Predictors for uroseptic shock in patients who undergo minimally invasive percutaneous nephrolithotomy. Urolithiasis 45 (6), https://doi.org/10.1007/s00240-017-0963-4. Singh, I,Shah, S,Gupta, S.Singh, N P, (2019) Efficacy of Intraoperative Renal Stone Culture in Predicting Postpercutaneous Nephrolithotomy Urosepsis/Systemic Inflammatory Response Syndrome: A Prospective Analytical Study with Review of Literature. J Endourol 33 (2), https://doi.org/10.1089/end.2018.0842. Del Moral-Trinidad, L E,Romo-Gonzalez, T,Carmona Figueroa, Y P,Barranca Enriquez, A,Palmeros Exsome, C.Campos-Uscanga, Y.(2021) Potential for body mass index as a tool to estimate body fat in young people. Enferm Clin (Engl Ed) 31 (2), https://doi.org/10.1016/j.enfcli.2020.06.080. Morokuma, F,Sadashima, E,Chikamatsu, S,Nakamura, T,Hayakawa, Y.Tokuda, N, (2020) The Risk Factors of Febrile Urinary Tract Infection After Ureterorenoscopic Lithotripsy. Kobe J Med Sci 66 (2). Pauchard, F,Ventimiglia, E,Corrales, M.Traxer, O, (2022) A Practical Guide for Intra-Renal Temperature and Pressure Management during Rirs: What Is the Evidence Telling Us. J Clin Med 11 (12), https://doi.org/10.3390/jcm11123429. Jia, Y,Zhao, Y,Li, C.Shao, R (2016) The Expression of Programmed Death-1 on CD4+ and CD8+ T Lymphocytes in Patients with Type 2 Diabetes and Severe Sepsis. PLoS One 11 (7), https://doi.org/10.1371/journal.pone.0159383. Dmitriyeva, M,Kozhakhmetova, Z,Urazova, S,Kozhakhmetov, S,Turebayev, D.Toleubayev, M, (2022) Inflammatory Biomarkers as Predictors of Infected Diabetic Foot Ulcer. Curr Diabetes Rev 18 (6), https://doi.org/10.2174/1573399817666210928144706. Aliyu, M,Zohora, F T,Anka, A U,Ali, K,Maleknia, S,Saffarioun, M, et al.(2022) Interleukin-6 cytokine: An overview of the immune regulation, immune dysregulation, and therapeutic approach. Int Immunopharmacol 111 , https://doi.org/10.1016/j.intimp.2022.109130. Qi, T,Lai, C,Li, Y,Chen, X.Jin, X, (2021) The predictive and diagnostic ability of IL-6 for postoperative urosepsis in patients undergoing percutaneous nephrolithotomy. Urolithiasis 49 (4), https://doi.org/10.1007/s00240-020-01237-z. Jia, W,Dou, W,Zeng, H,Wang, Q,Shi, P,Liu, J, et al.(2024) Diagnostic value of serum CRP, PCT and IL-6 in children with nephrotic syndrome complicated by infection: a single center retrospective study. Pediatr Res 95 (3), https://doi.org/10.1038/s41390-023-02830-9. Kazan, H O,Cakici, M C,Efiloglu, O,Cicek, M,Yildirim, A.Atis, R G, (2020) Clinical characteristics of postoperative febrile urinary tract infections after ureteroscopic lithotripsy in diabetics: Impact of glycemic control. Arch Esp Urol 73 (7). Baboudjian, M,Gondran-Tellier, B,Abdallah, R,Tadrist, A,Sichez, P C,Akiki, A, et al.(2021) Single use and reusable flexible ureteroscopies for the treatment of urinary stones: A comparative study of perioperative complications. Prog Urol 31 (6), https://doi.org/10.1016/j.purol.2020.11.014. Additional Declarations No competing interests reported. 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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-4183532","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":285633277,"identity":"8997e402-42ef-4311-9df0-2231f79a21f1","order_by":0,"name":"Feng Xiong","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAyUlEQVRIie3PMQrCMBTG8ZRCXB7WMQHBK8RFHAIexOWJkKlOrh3iHryLNwgWdNE9UgdFcNWxbioubkk3wfzn94P3ERKL/WBZ73Y+YS0ha+lAwnWeirNRXW5sIBE2p/xE11I4DP3M7i1DsCAOl5UjhRx7RbJYosDhEXil5kOyUTPtI2lKBCJcoV3lA5bo0k8ofc1BWgI57AIJAPT1m3QcBBLG6JRMjAJuXlswZMvIpdtHXctR1ipX7l5IP/lOMGxy/iFNRSwWi/1HT94gQLgewB5uAAAAAElFTkSuQmCC","orcid":"","institution":"The First Clinical Medical College of Three Gorges University, Three Gorges University","correspondingAuthor":true,"prefix":"","firstName":"Feng","middleName":"","lastName":"Xiong","suffix":""},{"id":285633278,"identity":"7bc5e283-b49d-471d-980d-7c9855c41bfc","order_by":1,"name":"Pan Zhang","email":"","orcid":"","institution":"The First Clinical Medical College of Three Gorges University, Three Gorges University","correspondingAuthor":false,"prefix":"","firstName":"Pan","middleName":"","lastName":"Zhang","suffix":""},{"id":285633279,"identity":"ba2e3d83-4724-4820-85f9-42d57df8703c","order_by":2,"name":"Xiangyi Fan","email":"","orcid":"","institution":"The First Clinical Medical College of Three Gorges University, Three Gorges University","correspondingAuthor":false,"prefix":"","firstName":"Xiangyi","middleName":"","lastName":"Fan","suffix":""},{"id":285633280,"identity":"029c7c6f-20ba-48bf-827a-9808f7f7fdef","order_by":3,"name":"Hongliang Qiao","email":"","orcid":"","institution":"The First Clinical Medical College of Three Gorges University, Three Gorges University","correspondingAuthor":false,"prefix":"","firstName":"Hongliang","middleName":"","lastName":"Qiao","suffix":""},{"id":285633281,"identity":"84261ab5-17f1-41c3-a8cc-034b8c5976ed","order_by":4,"name":"Zhongjun Cao","email":"","orcid":"","institution":"The First Clinical Medical College of Three Gorges University, Three Gorges University","correspondingAuthor":false,"prefix":"","firstName":"Zhongjun","middleName":"","lastName":"Cao","suffix":""},{"id":285633282,"identity":"f1c45b40-f1e1-4a35-859d-422563f65972","order_by":5,"name":"Xiaobo Chen","email":"","orcid":"","institution":"The First Clinical Medical College of Three Gorges University, Three Gorges University","correspondingAuthor":false,"prefix":"","firstName":"Xiaobo","middleName":"","lastName":"Chen","suffix":""}],"badges":[],"createdAt":"2024-03-28 16:16:37","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4183532/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4183532/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":54044887,"identity":"b3a45b44-5b24-45d2-96e1-7b40d04b501e","added_by":"auto","created_at":"2024-04-03 18:53:06","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":63426,"visible":true,"origin":"","legend":"\u003cp\u003eNomogram of UTI risk prediction model.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-4183532/v1/f8ff4fda578032180f4fb338.png"},{"id":54044454,"identity":"fe92814f-8850-48de-918d-8424564cb5d3","added_by":"auto","created_at":"2024-04-03 18:45:07","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":86673,"visible":true,"origin":"","legend":"\u003cp\u003eROC curve of UTI risk prediction model.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-4183532/v1/6156d98fcc41119e8e821544.png"},{"id":54044450,"identity":"441b2e1b-bcfc-4f89-8e41-7b3212c04021","added_by":"auto","created_at":"2024-04-03 18:45:06","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":46816,"visible":true,"origin":"","legend":"\u003cp\u003eCalibration curve of nomogram\u003cstrong\u003e \u003c/strong\u003eprediction model(\u003cstrong\u003eA\u003c/strong\u003e), Decision curve analysis (DCA) of nomogram prediction model(\u003cstrong\u003eB\u003c/strong\u003e)\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-4183532/v1/94d8722926e484df4c50277d.png"},{"id":54044452,"identity":"68d76cbb-cc45-433f-9c96-cd20c240a38b","added_by":"auto","created_at":"2024-04-03 18:45:06","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":201525,"visible":true,"origin":"","legend":"\u003cp\u003eAnalysis of pathogenic bacteria in urine culture\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-4183532/v1/e7c912e4e47b5ccb747a0c49.png"},{"id":54045283,"identity":"51ec7edf-5eb1-4bd5-b7ef-f7f39f58e22e","added_by":"auto","created_at":"2024-04-03 19:01:11","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":734882,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4183532/v1/3da518db-5ec3-4926-a08c-4ad9d48c9481.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Risk factors analysis of Flexible Ureteroscopic Lithotripsy with UTI and construction of clinical prediction model","fulltext":[{"header":"Introduction","content":"\u003cp\u003eUrinary calculi are common diseases in the urinary tract, with an incidence of up to 59% in Europe and about 15% in Asia\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e. The treatments for urinary stones include conservative treatment, ureterolithotomy, Extracorporeal Shock Wave Lithotripsy (ESWL), percutaneous nephrolithotomy (PCNL), and ureteroscopic lithotomy (URL). Flexible Ureteroscopic Lithotripsy (FURL) has the advantages of being slender, soft, and flexible, allowing it to leverage its unique benefits in treating specific cases of kidney stones, such as calyceal diverticulum, horseshoe kidney stones, ectopic kidney stones, polycystic kidney stones, isolated kidney stones, and other complex stones. It can ensure a high rate of stone clearance without leading to serious postoperative complications\u003csup\u003e[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]\u003c/sup\u003e. Various complications can occur after FURL, and the overall complication rate is about 9% \u0026ndash; 25%\u003csup\u003e[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]\u003c/sup\u003e. Urinary tract infection (UTI), ureteral injury, hematuria, and postoperative renal colic are common complications of FURL. UTI is one of the most common postoperative complications, causing systemic inflammatory response syndrome (SIRS), urogenic sepsis, and even septic shock\u003csup\u003e[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]\u003c/sup\u003e. The postoperative fever rate is about 26%, the probability of sepsis is about 2%~8%, and the mortality rate is about 20%~42%, which seriously harms the economy and life safety of the patient\u003csup\u003e[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]\u003c/sup\u003e.Although the fever rate after FURL and ESWL was significantly lower than after PCNL, infections were still inevitable.\u003c/p\u003e \u003cp\u003eCurrently, there are numerous and diverse risk factors associated with postoperative febrile urinary tract infections in FURL\u003csup\u003e[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]\u003c/sup\u003e. Ureteroscopy surgery continues to be a hot and challenging topic in the research field. Differences in case numbers, inclusion criteria, statistical methods, and other factors in previous studies have resulted in varying conclusions\u003csup\u003e[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]\u003c/sup\u003e, necessitating additional research and investigation.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePatients\u003c/h2\u003e \u003cp\u003eWe retrospectively identified the data of patients with renal stones who received FURL in our hospital, a tertiary hospital with the highest level of referral directly under National Healthy Committee of China, from January 2021 to January 2023. The study was approved by the Institutional Ethics Committee of the First Clinical Medical College of the China Three Gorges University.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eInclusion and exclusion criteria\u003c/h2\u003e \u003cp\u003eInclusion criteria: (1) There is imaging data confirming the presence of urinary calculi, along with clear indications for surgery; (2) UTI following flexible ureteral lithotripsy; excluding infections from other systems.(3) Hospital stay\u0026thinsp;\u0026gt;\u0026thinsp;3 days; (4) The clinical data are complete, accurate, and available.\u003c/p\u003e \u003cp\u003eExclusion criteria: (1) Accompanied by heart, liver, spleen, lung, kidney and other important organ failure; (2) Combined with autoimmune system and hematological system diseases; (3)The hospitalization data are incomplete, and the examinations are not perfect; (4) Serious complications or complications during the treatment process require other treatment.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eDiagnostic Standard\u003c/h2\u003e \u003cp\u003eUrinary tract infections: patient symptoms (lower urinary tract infection: frequent urination, urgent urination, urination pain, hematuria, and lumbosacral pain; upper urinary tract infections: fever, low back pain, nausea, vomiting, and other systemic symptoms), medical history (urinary surgery, history of diabetes, history of related drug use, etc.), and signs (fever, back pain, rib and ridge horn tenderness or percussion pain, etc.), one or more suggest a urinary tract infection. Having any one of the following three conditions: body temperature\u0026thinsp;\u0026gt;\u0026thinsp;38.5\u0026deg;C, positive urine culture, and positive blood culture. Additionally, exclude other factors and infections induced by the system.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eClinical data collection\u003c/h2\u003e \u003cp\u003eAll patient information is obtained from the inpatient medical record system, imaging system, and surgical anesthesia system. We collected and analyzed the following factors: (1) General information: Age, Gender, BMI, ASA, basic diseases (such as hypertension, diabetes, renal insufficiency), previous history of stone surgery, hydronephrosis, preoperative infection history, preoperative antibiotic use time, and retention time of urinary catheter; (2) Laboratory indicators: blood routine, blood biochemistry, blood uric acid, urine routine (urine protein, urine occult blood, urine nitrite, urine white blood cells), preoperative urine culture, coagulation function, cytokines (IL-6, TNF-α); (3) Surgical information: surgical time, bleeding volume, perfusion volume, ureteral stent placement, nephrostomy tube placement, ureteral stenosis; (4) Imaging data: Abdominal plain film (KUB), color ultrasonography, excretory urography (IVU), non-contrast computed tomography (CT), characteristics of stones (single or multiple, size, location, side), maximum diameter of stones, CT value of stones, stone components (infectious stones, calcium stones, cystine stones, uric acid stones, etc).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eSurgical methods\u003c/h2\u003e \u003cp\u003eFor patients with positive preoperative urine culture, sensitive antibiotics should be used based on drug sensitivity results, and surgery should be performed after the urine culture results turn negative. All patients received prophylactic use of antibiotics (cephalosporin) at 30 points before surgery. If the patient's urine culture was positive before surgery, they were replaced with sensitive antibiotics.\u003c/p\u003e \u003cp\u003eAfter the induction of general anesthesia in the lithotomy position, F8/9.8 ureteroscope (Wolf, Germany) was inserted into the bladder to explore the ureter on the affected side. A zebra-guide wire was inserted from the ureteral orifice to the renal pelvis. F12/14or F14/16 ureteral access sheath (based on gender and ureteral condition) was inserted into the upper ureter near the junction of the renal pelvis. Subsequently, the guidewire was removed, and the flexible ureteroscope (Olympus, Japan) was advanced through the ureteral access sheath into the renal collecting system. Stones were then located and fragmented using a holmium laser. Finally, an F5/6 ureteral stent was inserted, and the operation was completed.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eSPSS(22.0) and R(4.2.1) software were used for statistical analysis. Normally distributed continuous variables were presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (x\u0026thinsp;\u0026plusmn;\u0026thinsp;s), while non-normally distributed continuous variables were presented as median. The comparison between groups was conducted using t-tests or Mann-Whitney U tests. Categorical variables were analyzed using the χ2 test or Fisher's exact test and presented as numbers (n) and percentages (%). Univariate and multivariate logistic regression models were conducted to ascertain the independent effect of risk factors for postoperative UTI following FURL. Variables showing a P value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 in univariable analysis were considered as candidates for the multivariable model. Receiver Operating Characteristic curve (ROC), concordance index (c-index), and calibration curves were performed to assess the accuracy of the prediction model. Decision Curve Analysis (DCA) was used to calculate the net benefit threshold for clinical interventions.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e\n\u003ch2\u003eUnivariate Analysis Results\u003c/h2\u003e\n\u003cp\u003eAccording to the inclusion and exclusion criteria, a total of 560 patients were enrolled, including 386 males (69%) and 174 females (31%), with an average age (51.03\u0026thinsp;\u0026plusmn;\u0026thinsp;13.67) years and an average BMI (24.43\u0026thinsp;\u0026plusmn;\u0026thinsp;3.19) kg/m.\u003csup\u003e2\u003c/sup\u003e Of these, 111 patients developed UTI after FUTL, The postoperative infection rate was 19.8%. The basic characteristics of these patients were summarized in Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e. Univariate analysis of the risk factors showed that UTI was associated with renal insufficiency (\u0026chi;2\u0026thinsp;=\u0026thinsp;38.959, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), Preoperative UTI (\u0026chi;2\u0026thinsp;=\u0026thinsp;35.797, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), Preoperative ureteral stent placement (\u0026chi;2\u0026thinsp;=\u0026thinsp;30.174, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), Ureteral stenosis (\u0026chi;2\u0026thinsp;=\u0026thinsp;12.050, P\u0026thinsp;=\u0026thinsp;0.001), Preoperative antibiotic use duration (Z\u0026thinsp;=\u0026thinsp;3.637, P\u0026thinsp;=\u0026thinsp;0.003), IL-6(\u0026chi;2\u0026thinsp;=\u0026thinsp;98.112, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), Uric acid (\u0026chi;2\u0026thinsp;=\u0026thinsp;13.643, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), Preoperative urine culture (\u0026chi;2\u0026thinsp;=\u0026thinsp;50.578, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), Urinary nitrite (\u0026chi;2\u0026thinsp;=\u0026thinsp;70.835, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), Urinary leukocytes (\u0026chi;2\u0026thinsp;=\u0026thinsp;7.996, P\u0026thinsp;=\u0026thinsp;0.005), History of stone surgery(\u0026chi;2\u0026thinsp;=\u0026thinsp;19.207,P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), Stone diameter (Z=-4.343, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001), Operative duration (Z=-3.442,P\u0026thinsp;=\u0026thinsp;0.001), Irrigation volume(Z=-3.567, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), Stone composition (\u0026chi;2\u0026thinsp;=\u0026thinsp;81.826, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n\u003ctable id=\"Tab1\" border=\"1\"\u003e\u003ccaption\u003e\n\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n\u003cdiv class=\"CaptionContent\"\u003e\n\u003cp\u003eRisk factors for urinary tract infections after FURL\u003c/p\u003e\n\u003c/div\u003e\n\u003c/caption\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eRisk factor\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eUTI(n\u0026thinsp;=\u0026thinsp;111)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eNon-UTI(n\u0026thinsp;=\u0026thinsp;449)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003et/Z/\u0026chi;2\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e\n\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eAge (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD), years\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e51.97\u0026thinsp;\u0026plusmn;\u0026thinsp;13.58\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e50.80\u0026thinsp;\u0026plusmn;\u0026thinsp;13.69\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e-0.813\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.417\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eBMI (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD), kg/m\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e24.33\u0026thinsp;\u0026plusmn;\u0026thinsp;2.88\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e24.45\u0026thinsp;\u0026plusmn;\u0026thinsp;3.27\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.374\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.709\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eGender, n(%)\u003c/p\u003e\n\u003cp\u003eMale\u003c/p\u003e\n\u003cp\u003efemale\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e73(65.77)\u003c/p\u003e\n\u003cp\u003e38(34.23)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e313(69.7)\u003c/p\u003e\n\u003cp\u003e136(30.3)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.647\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.421\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eASA-PS, n(%)\u003c/p\u003e\n\u003cp\u003e1\u003c/p\u003e\n\u003cp\u003e2\u003c/p\u003e\n\u003cp\u003e3\u003c/p\u003e\n\u003cp\u003e4\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3(2.70)\u003c/p\u003e\n\u003cp\u003e76(68.47)\u003c/p\u003e\n\u003cp\u003e30(27.03)\u003c/p\u003e\n\u003cp\u003e2(1.80)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e9(2)\u003c/p\u003e\n\u003cp\u003e328(73)\u003c/p\u003e\n\u003cp\u003e108(24.1)\u003c/p\u003e\n\u003cp\u003e4(0.9)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e-0.727\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.467\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eHypertension, n(%)\u003c/p\u003e\n\u003cp\u003eYes\u003c/p\u003e\n\u003cp\u003eno\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e36(32.43)\u003c/p\u003e\n\u003cp\u003e75(67.57)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e125(27.8)\u003c/p\u003e\n\u003cp\u003e324(72.2)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.916\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.338\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eDiabetes, n(%)\u003c/p\u003e\n\u003cp\u003eYes\u003c/p\u003e\n\u003cp\u003eNo\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e14(12.61)\u003c/p\u003e\n\u003cp\u003e97(87.39)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e59(13.14)\u003c/p\u003e\n\u003cp\u003e390(86.86)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.022\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.882\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eRenal dysfunction, n(%)\u003c/p\u003e\n\u003cp\u003eYes\u003c/p\u003e\n\u003cp\u003eNo\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e69(62.16)\u003c/p\u003e\n\u003cp\u003e42(37.84)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e136(30.29)\u003c/p\u003e\n\u003cp\u003e313(69.71)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e38.959\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eHydronephrosis, n(%)\u003c/p\u003e\n\u003cp\u003eYes\u003c/p\u003e\n\u003cp\u003eNo\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e70(63.06)\u003c/p\u003e\n\u003cp\u003e41(36.94)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e238(53.01)\u003c/p\u003e\n\u003cp\u003e211(46.99)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e3.637\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.057\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePreoperative UTI, n(%)\u003c/p\u003e\n\u003cp\u003eYes\u003c/p\u003e\n\u003cp\u003eNo\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e30(27.03)\u003c/p\u003e\n\u003cp\u003e81(72.97)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e32(7.13)\u003c/p\u003e\n\u003cp\u003e417(92.87)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e35.797\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePreoperative ureteral stenting, n(%)\u003c/p\u003e\n\u003cp\u003eYes\u003c/p\u003e\n\u003cp\u003eNo\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e26(23.42)\u003c/p\u003e\n\u003cp\u003e85(76.58)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e28(6.24)\u003c/p\u003e\n\u003cp\u003e421(96.76)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e30.174\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003enephrostomy, n(%)\u003c/p\u003e\n\u003cp\u003eYes\u003c/p\u003e\n\u003cp\u003eNo\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e10(9.01)\u003c/p\u003e\n\u003cp\u003e101(90.99)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e21(4.68)\u003c/p\u003e\n\u003cp\u003e428(95.32)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e3.194\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.074\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eUreteral stricture, n(%)\u003c/p\u003e\n\u003cp\u003eYes\u003c/p\u003e\n\u003cp\u003eNo\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e41(36.94)\u003c/p\u003e\n\u003cp\u003e70(63.06)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e95(21.16)\u003c/p\u003e\n\u003cp\u003e354(78.84)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e12.050\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eIL-6(pg/ml), n(%)\u003c/p\u003e\n\u003cp\u003e\u0026le;5.3\u003c/p\u003e\n\u003cp\u003e\u0026gt;5.3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e33(29.73)\u003c/p\u003e\n\u003cp\u003e78(70.27)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e352(78.40)\u003c/p\u003e\n\u003cp\u003e97(21.60)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e98.112\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eTNF-\u0026alpha;(pg/ml), n(%)\u003c/p\u003e\n\u003cp\u003e\u0026le;4.6\u003c/p\u003e\n\u003cp\u003e\u0026gt;4.6\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e65(58.56)\u003c/p\u003e\n\u003cp\u003e46(41.44)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e304(67.71)\u003c/p\u003e\n\u003cp\u003e145(32.29)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e3.314\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.069\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ecreatinine(umol/L), n(%)\u003c/p\u003e\n\u003cp\u003e\u0026lt;44\u003c/p\u003e\n\u003cp\u003e44\u0026ndash;133\u003c/p\u003e\n\u003cp\u003e\u0026gt;133\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3(2.70)\u003c/p\u003e\n\u003cp\u003e81(72.97)\u003c/p\u003e\n\u003cp\u003e27(24.32)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4(0.89)\u003c/p\u003e\n\u003cp\u003e368(81.96)\u003c/p\u003e\n\u003cp\u003e77(17.15)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e5.137\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.077\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eurea nitrogen(mmol/L), n(%)\u003c/p\u003e\n\u003cp\u003e\u0026lt;3.6\u003c/p\u003e\n\u003cp\u003e3.6\u0026ndash;9.5\u003c/p\u003e\n\u003cp\u003e\u0026gt;9.5\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e9(8.11)\u003c/p\u003e\n\u003cp\u003e80(72.07)\u003c/p\u003e\n\u003cp\u003e22(19.82)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e27(6.01)\u003c/p\u003e\n\u003cp\u003e363(80.85)\u003c/p\u003e\n\u003cp\u003e59(13.14)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e4.219\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.121\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ealbumin(g/L), n(%)\u003c/p\u003e\n\u003cp\u003e\u0026lt;35\u003c/p\u003e\n\u003cp\u003e\u0026ge;\u0026thinsp;35\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e26(23.42)\u003c/p\u003e\n\u003cp\u003e85(76.58)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e73(16.26)\u003c/p\u003e\n\u003cp\u003e376(83.74)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e3.140\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.076\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003euric acid(umol/L), n(%)\u003c/p\u003e\n\u003cp\u003e\u0026le;\u0026thinsp;430\u003c/p\u003e\n\u003cp\u003e\u0026gt;430\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e64(57.66)\u003c/p\u003e\n\u003cp\u003e47(42.34)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e338(75.28)\u003c/p\u003e\n\u003cp\u003e111(24.72)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e13.643\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePreoperative urine culture, n(%)\u003c/p\u003e\n\u003cp\u003eNegative\u003c/p\u003e\n\u003cp\u003ePositive\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e87(78.38)\u003c/p\u003e\n\u003cp\u003e24(21.62)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e436(97.10)\u003c/p\u003e\n\u003cp\u003e13(2.90)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e50.578\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eurinary protein, n(%)\u003c/p\u003e\n\u003cp\u003eNegative\u003c/p\u003e\n\u003cp\u003ePositive\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e65(58.56)\u003c/p\u003e\n\u003cp\u003e46(41.44)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e300(66.82)\u003c/p\u003e\n\u003cp\u003e149(33.18)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e2.673\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.102\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eurinary occult blood, n(%)\u003c/p\u003e\n\u003cp\u003eNegative\u003c/p\u003e\n\u003cp\u003ePositive\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e36(32.43)\u003c/p\u003e\n\u003cp\u003e75(67.57)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e179(39.87)\u003c/p\u003e\n\u003cp\u003e270(60.13)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e2.079\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.149\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eUrinary leukocyte, n(%)\u003c/p\u003e\n\u003cp\u003eNegative\u003c/p\u003e\n\u003cp\u003ePositive\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e49(44.14)\u003c/p\u003e\n\u003cp\u003e62(55.86)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e265(59.02)\u003c/p\u003e\n\u003cp\u003e184(40.98)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e7.996\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.005\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eUrinary nitrite, n(%)\u003c/p\u003e\n\u003cp\u003eNegative\u003c/p\u003e\n\u003cp\u003ePositive\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e64(57.66)\u003c/p\u003e\n\u003cp\u003e47(42.34)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e406(90.42)\u003c/p\u003e\n\u003cp\u003e43(9.58)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e70.835\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eHistory of stone surgery, n(%)\u003c/p\u003e\n\u003cp\u003eNo\u003c/p\u003e\n\u003cp\u003eYes\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e70(63.06)\u003c/p\u003e\n\u003cp\u003e41(36.94)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e369(82.18)\u003c/p\u003e\n\u003cp\u003e80(17.82)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e19.207\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eStone location, n(%)\u003c/p\u003e\n\u003cp\u003eUreter\u003c/p\u003e\n\u003cp\u003eRenal pelvis\u003c/p\u003e\n\u003cp\u003eMultiple stone\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e38(34.23)\u003c/p\u003e\n\u003cp\u003e59(53.15)\u003c/p\u003e\n\u003cp\u003e14(12.61)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e191(42.54)\u003c/p\u003e\n\u003cp\u003e185(41.20)\u003c/p\u003e\n\u003cp\u003e73(16.26)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e5.180\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.075\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eNumber of stones, n(%)\u003c/p\u003e\n\u003cp\u003eSingle\u003c/p\u003e\n\u003cp\u003eMultiple\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e71(63.96)\u003c/p\u003e\n\u003cp\u003e40(36.04)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e327(72.83)\u003c/p\u003e\n\u003cp\u003e122(27.17)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e3.402\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.065\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eStone laterality,n(%)\u003c/p\u003e\n\u003cp\u003eUnilateral\u003c/p\u003e\n\u003cp\u003eBilateral\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e96(86.49)\u003c/p\u003e\n\u003cp\u003e15(13.51)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e411(91.54)\u003c/p\u003e\n\u003cp\u003e38(8.46)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e2.649\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.104\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eStone diameter(mm)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.9(0.7, 1.0)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.7(0.6, 0.9)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e-4.343\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eCT value (HU)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e618(489, 819)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e715(516, 876)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e-1.319\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.187\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eOperative duration (min)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e85(60, 120)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e70(55, 95)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e-3.422\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eBlood loss (ml)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e10(5, 20)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e5(5, 10)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e-1.706\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.088\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eIrrigation volume (ml)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e960(690, 1225)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e790(655, 1048)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e-3.567\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eCatheter placement period (D)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e2(1, 3)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e2(1, 3)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e-0.71\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.481\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePreoperative antibiotic usage time (D)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e1(0, 4)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0(0, 3)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e-2.948\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.003\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eStone components, n(%)\u003c/p\u003e\n\u003cp\u003eInfectious stones\u003c/p\u003e\n\u003cp\u003eCalcium stones\u003c/p\u003e\n\u003cp\u003eCysteine stones\u003c/p\u003e\n\u003cp\u003eUric acid stones\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e43(38.74)\u003c/p\u003e\n\u003cp\u003e46(41.44)\u003c/p\u003e\n\u003cp\u003e3(2.70)\u003c/p\u003e\n\u003cp\u003e19(17.12)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e32(7.13)\u003c/p\u003e\n\u003cp\u003e372(82.85)\u003c/p\u003e\n\u003cp\u003e11(2.45)\u003c/p\u003e\n\u003cp\u003e34(7.57)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e81.826\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003ctfoot\u003e\n\u003ctr\u003e\n\u003ctd colspan=\"5\"\u003e\u003cstrong\u003e*P\u0026lt;0.05 BMI\u003c/strong\u003e:body mass index; \u003cstrong\u003eASA-PS\u003c/strong\u003e:American Society of Anesthesiologists physical status classification system; \u003cstrong\u003eIL-6\u003c/strong\u003e:Interleukin-6; \u003cstrong\u003eTNF-\u0026alpha;\u003c/strong\u003e:Tumor Necrosis Factor-\u0026alpha;\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tfoot\u003e\n\u003c/table\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\n\u003ch2\u003eUnivariate and Multivariate Logistic Regression Analysis Results\u003c/h2\u003e\n\u003cp\u003eIn the univariate analysis, significant differences were observed between groups with UTI and non-UTI in terms of renal dysfunction, preoperative UTI, preoperative ureteral stent placement, positive preoperative urine culture, positive urinary leukocyte, positive urine nitrite, IL-6\u0026thinsp;\u0026gt;\u0026thinsp;5.3 pg/ml, uric acid\u0026thinsp;\u0026gt;\u0026thinsp;430 umol/L, history of stone surgery, irrigation volume, ureteral stenosis, stone diameter, preoperative antibiotic use duration, and operative duration. In the multivariate analysis, renal dysfunction [OR\u0026thinsp;=\u0026thinsp;2.103 (95% CI: 1.134, 3.907), P\u0026thinsp;=\u0026thinsp;0.018], preoperative urine culture [OR\u0026thinsp;=\u0026thinsp;6.070 (95% CI: 1.800, 20.474), P\u0026thinsp;=\u0026thinsp;0.004], positive urine nitrite [OR\u0026thinsp;=\u0026thinsp;3.206 (95% CI: 1.599, 6.429), P\u0026thinsp;=\u0026thinsp;0.001], IL-6\u0026thinsp;\u0026gt;\u0026thinsp;5.3 pg/ml [OR\u0026thinsp;=\u0026thinsp;6.876 (95% CI: 3.734, 12.661), P\u0026thinsp;\u0026lt;\u0026thinsp;0.001], Uric acid\u0026thinsp;\u0026gt;\u0026thinsp;430 umol/L [OR\u0026thinsp;=\u0026thinsp;2.024 (95% CI: 1.088, 3.765), P\u0026thinsp;=\u0026thinsp;0.026], and Ureteral stenosis [OR\u0026thinsp;=\u0026thinsp;3.174 (95% CI: 1.660, 6.070), P\u0026thinsp;\u0026lt;\u0026thinsp;0.001] were independently associated with UTI(Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n\u003ctable id=\"Tab2\" border=\"1\"\u003e\u003ccaption\u003e\n\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n\u003cdiv class=\"CaptionContent\"\u003e\n\u003cp\u003eUnivariate and multivariate logistic regression analysis of risk factors for UTI\u003c/p\u003e\n\u003c/div\u003e\n\u003c/caption\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth rowspan=\"2\" align=\"left\"\u003e\n\u003cp\u003eRisk factor\u003c/p\u003e\n\u003c/th\u003e\n\u003cth colspan=\"2\" align=\"left\"\u003e\n\u003cp\u003eUnivariate logistics\u003c/p\u003e\n\u003c/th\u003e\n\u003cth colspan=\"2\" align=\"left\"\u003e\n\u003cp\u003eMultivariate logistics\u003c/p\u003e\n\u003c/th\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eOR(95%CI)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eOR(95%CI)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e\n\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eRenal dysfunction\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e3.781(2.452\u0026ndash;5.831)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e2.103(1.134\u0026ndash;3.901)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.003\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePreoperative UTI\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e4.826(2.779\u0026ndash;8.382)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e2.071(0.827\u0026ndash;5.185)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.120\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePreoperative ureteral stenting\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e4.599(2.569\u0026ndash;8.235)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.481(0.585\u0026ndash;3.749)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.407\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePositive Preoperative urine culture\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e9.252(4.535\u0026ndash;18.877)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e6.070(1.800-20.474)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.004\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePositive Urinary leukocyte\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.822(1.198\u0026ndash;2.771)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.005\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.806(0.438\u0026ndash;1.483)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.488\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePosotive Urinary nitrite\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e6.934(4.246\u0026ndash;11.324)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e3.206(1.599\u0026ndash;6.429)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eIL6\u0026gt;5.3 pg/ml\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e8.577(5.388\u0026ndash;13.654)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e6.876(3.734\u0026ndash;12.661)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003euric acid\u0026gt;430 umol/L\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e2.236(1.450\u0026ndash;3.449)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e2.024(1.088\u0026ndash;3.765)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.026\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eHistory of stone surgery\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e2.702(1.714\u0026ndash;4.258)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.440(0.740\u0026ndash;2.804)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.283\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eIrrigation volume\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.001(1.001\u0026ndash;1.002)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.002(0.999\u0026ndash;1.004)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.280\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eUreteral stricture\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e2.183(1.396\u0026ndash;3.413)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e3.174(1.660\u0026ndash;6.070)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eStone diameter\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e3.211(1.581\u0026ndash;6.522)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e2.336(0.764\u0026ndash;7.144)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.137\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePreoperative antibiotic usage time\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.091(1.026\u0026ndash;1.161)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.006\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.895(0.799\u0026ndash;1.002)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.054\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eOperative duration\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.009(1.003\u0026ndash;1.014)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.001\u003cstrong\u003e*\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.993(0.972\u0026ndash;1.015)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.545\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003ctfoot\u003e\n\u003ctr\u003e\n\u003ctd colspan=\"5\"\u003e\u003cstrong\u003e*P\u0026lt;0.05 CI\u003c/strong\u003e:confidence interval\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tfoot\u003e\n\u003c/table\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\n\u003ch2\u003eEstablishment and Evaluation of Nomogram model\u003c/h2\u003e\n\u003cp\u003eBased on the results of the Multivariate Logistic Regression Analysis, visualize each independent risk factor in the nomogram model(Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e). The influence of each independent risk factor on the occurrence of postoperative urinary tract infection is presented in segmented values. The sum of the scores in the nomogram model indicates the likelihood of UTI. The results of ROC curve analysis showed the area under the curve (AUC) for each independent risk factor and the Nomogram prediction model(Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e).The AUC of the nomogram prediction model was 0.90 (95% CI: 0.876\u0026ndash;0.937). The calibration curve of the prediction model is shown in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003cstrong\u003eA\u003c/strong\u003e Validation of the nomogram model was performed using a 1000-bootstrap analysis. the calculated C-index\u0026thinsp;=\u0026thinsp;0.834, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.301,which showed good fitting of the nomogram model.The DCA curve for the predictive nomogram is presented in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003cstrong\u003eB\u003c/strong\u003e, demonstrating significant net benefits of the predictive nomogram. When the event incidence ranges from 1\u0026ndash;70%, the application of the prediction model may yield a net benefit in clinical intervention. However, when the incidence exceeds the 70% threshold, the prediction model does not provide significant benefits. Overall, the predictive nomogram model showed a strong correlation with the actual observed values, indicating its relative accuracy and consistency.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\n\u003ch2\u003eComparative analysis of positive pathogenic bacteria in urine cultures\u003c/h2\u003e\n\u003cp\u003eIn this study, the bacterial distribution of urine cultures in the UTI group and non-UTI group is illustrated in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e. Among the 560 patients enrolled, a total of 37 cases had a positive urine culture, resulting in a positive urinary culture rate of 6.6%. Specifically, 24 (21.6%) out of 111 patients in the UTI group and 13 (2.9%) out of 449 patients in the non-UTI group. The positive rate of urine culture in the UTI group was higher than that in the non-UTI group. Most of the pathogenic bacteria in the two groups were gram-negative bacteria, mainly E. coli (54.1%), followed by Klebsiella pneumoniae (10.8%).The main Gram-positive bacteria were Enterococcus faecalis (10.8%).\u003c/p\u003e\n\u003cp\u003eThere are research reports indicating that selecting medication based on preoperative urine culture results is sometimes unreliable, as the bacterial findings of preoperative urine culture and stone bacterial culture do not always align. In a single-center retrospective study conducted by Paonessa[\u003csup\u003e[\u003cspan class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/sup\u003e], 352 (45.4%) out of 776 cases tested positive for urine culture, and 300 (38.7%) were positive for stone culture.Among patients who tested positive for both cultures, 103 (13.3%) had differences in the pathogens. The cultured bacteria were mainly Staphylococcus, followed by E-coli. 13.7% of the patients with positive stone cultures were Enterococcus faecalis, which is not covered by common cephalosporins and is also resistant to fluoroquinolones commonly used in the urinary system. Inappropriate antimicrobial treatment may delay recovery, leading to worsening of the infection.\u003c/p\u003e\n\u003cp\u003eIn an international, multicenter study[\u003csup\u003e[\u003cspan class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/sup\u003e], 865 out of 5803 patients who underwent PCNL had positive urine cultures (16.2%), with Escherichia coli being the main pathogen. Compared to other continents, patients in the Americas had the lowest proportion of Escherichia coli in urine cultures (20.9%), with Gram-positive bacteria being the dominant strain. This study's findings are akin to those of Paonessa and our own research. One current limitation is that our hospital has not conducted intraoperative stone culture on patients undergoing stone surgery. Additionally, the sample size of positive urine cultures is too small to verify the consistency between preoperative urine culture and stone culture results. Therefore, establishing a bacterial spectrum through urine culture and stone culture is an important step in prescribing preventive antibiotics and treating urinary tract infections.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eUrinary calculi are common diseases of the urinary system, especially upper urinary tract calculi, with an incidence of about 25%\u003csup\u003e[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/sup\u003e. It can cause urinary tract obstruction, kidney damage, and even renal failure\u003csup\u003e[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]\u003c/sup\u003e. Stones can be treated with open lithotomy, PCNL, ESWL, and URL. Open lithotomy requires the patient's surgical tolerance and body shape. An underweight or overweight body can complicate the surgery, lead to significant surgical trauma, and negatively impact the patient's prognosis. Postoperative bleeding and tissue adhesion in the surgical area can lead to challenges in subsequent stone removal, a procedure that is currently less frequently employed in clinical practice. ESWL is only appropriate for small stones and is not recommended for patients with large stones, infections, or ureteral strictures. PCNL is suitable for kidney stones and stones at the junction of the ureter, but not for middle and lower ureteral stones. As an invasive procedure, surgery is challenging, significantly impacting the patient and carrying a high risk of bleeding. With advancements in medical equipment and laser technology, URS has gradually emerged as the \"gold standard\" for treating upper ureteral and kidney stones due to its safety and minimally invasive nature\u003csup\u003e[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]\u003c/sup\u003e. A total of 560 patients were enrolled in this study, with 111 in the UTI group and 449 in the non-UTI group. Excluding postoperative infection and other systemic infections, the rate of postoperative urinary tract infection was approximately 19.8%, which is similar to the rate reported by Yamashita (20%). Univariate analysis revealed that the UTI group had larger values than the non-infected group in terms of intraoperative perfusion amount, stone diameter, preoperative antibiotic use time, and operation time (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Multivariate logistic regression analysis indicated that renal dysfunction, positive preoperative urine culture, positive urinary nitrite, IL-6\u0026thinsp;\u0026gt;\u0026thinsp;5.3 pg/ml, blood uric acid\u0026thinsp;\u0026gt;\u0026thinsp;430 umol/L, and ureteral stenosis were independent risk factors for UTI after FURL.\u003c/p\u003e \u003cp\u003eAt present, the predictive value of a positive preoperative urine culture (UC) for UTI after FURL is still controversial. Some studies have considered preoperative urine culture to be of predictive value\u003csup\u003e[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]\u003c/sup\u003e, while others have reported that preoperative urine cultures are not accurate enough to have predictive value due to stone-induced urinary obstruction\u003csup\u003e[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]\u003c/sup\u003e. Most stones contain a large amount of colonized bacteria and endotoxins. Preoperative stone entrapment and polyp wrapping can cause partial or complete obstruction of the urinary system, leading to hydronephrosis and ureteral fluid accumulation, which creates an environment favorable for bacterial growth. Urine carrying bacteria cannot flow down to the bladder due to urinary tract obstruction, resulting in negative urine culture results.Therefore, the UC cannot accurately reflect the microbial status of upper urinary tract urine. In addition, a large amount of physiological saline is required for high-pressure infusion during ureteroscopic lithotripsy to maintain a clear field of view during the operation. As the perfusion pressure increases, the perfusion fluid can reflux through various channels such as renal pelvic veins, renal tubules, and lymph nodes. This can cause bacteria and endotoxins in the stones to reflux into the bloodstream, leading to sepsis and even septic shock. In our study, a positive preoperative urine culture not only refers to a positive result from the last preoperative urine culture but also to at least one occurrence of a positive urine culture result among several preoperative urine culture results from the patient's admission to surgery.Urinary tract obstruction and prolonged use of antibiotics can lead to false negative results in preoperative urine culture in patients. The study by Chen, Kreydin, and others also reported that a negative preoperative urine culture is not sufficient to rule out the risk of postoperative urinary tract infections\u003csup\u003e[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]\u003c/sup\u003e. For patients with positive urine culture results, we will choose appropriate antibiotics for treatment according to the sensitivity of the culture results. Surgery will be performed after the urine culture results turn negative. Singh's research suggests that renal pelvis puncture urine culture can better predict Systemic Inflammatory Response Syndrome (SIRS) than standard urine culture\u003csup\u003e[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]\u003c/sup\u003e. However, using intraoperative puncture urine culture to predict postoperative infections has limited early predictive value due to the long cultivation time, and it lacks high clinical practicality.\u003c/p\u003e \u003cp\u003eSome studies have found a rapid and convenient non-molecular diagnostic method: urinary nitrite. When gram-negative bacteria infect the body, bacteria containing reductase can convert nitrate in urine into nitrite. Positive urine nitrite often indicates a bacterial infection, with high specificity (98%) but low sensitivity (only 23\u0026ndash;43%)\u003csup\u003e[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]\u003c/sup\u003e. Some bacteria do not contain nitrate reductase, which is a limitation of this method. When infected with this type of bacteria, the urine nitrite test result will be negative. Although there are limitations, urinary nitrite is also widely used as an indirect indicator for diagnosing bacterial urine. According to the nomogram prediction chart model, the scores for a positive urine culture and positive urine nitrite before the operation were 86 and 77 points, respectively. These scores are highly valuable in predicting postoperative urinary tract infections.\u003c/p\u003e \u003cp\u003eBMI is a key indicator used in clinics to determine whether patients are obese or not. With the increase in BMI, the prevalence of cardiovascular and cerebrovascular diseases, diabetes, and other risk factors will also increase. As fat accumulates in obese patients, the plasma osmolality increases, disrupting the dynamic balance of the internal environment and leading to a decrease in immune cell function\u003csup\u003e[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]\u003c/sup\u003e. A study has found that BMI\u0026thinsp;\u0026ge;\u0026thinsp;25 or higher is an independent risk factor for systemic inflammatory response syndrome after PCNL\u003csup\u003e[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]\u003c/sup\u003e. Another study found that a low BMI was also an important risk factor for UTI after surgeries[\u003csup\u003e[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]\u003c/sup\u003e]. However, the number of positive samples is only 3, so more studies with larger samples are needed to verify it.Some studies suggest that diabetic patients with poor glycemic control have a higher risk of urinary tract infection (UTI) following surgery\u003csup\u003e[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]\u003c/sup\u003e. The long-term high glucose state in diabetic patients can lead to tissue circulation disorders, followed by tissue ischemia and hypoxia, which can increase the risk of tissue necrosis. Additionally, during hyperglycemia, the body's ability for leukocyte movement and phagocytosis decreases, leading to a decline in immune function\u003csup\u003e[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]\u003c/sup\u003e. Our study showed that BMI and diabetes were not independent risk factors for UTI after furs, which may be attributed to regional patient factors.For patients with pre-operative hyperglycemia, we will regulate blood glucose levels to normal before surgery to reduce the postoperative infection rate. For patients with diabetes mellitus, the current consensus both domestically and internationally is that maintaining good preoperative blood glucose control will significantly reduce the likelihood of postoperative infections.\u003c/p\u003e \u003cp\u003eInterleukin-6 (IL-6) is a cytokine with multiple biological activities, participating in systemic infections, autoimmune diseases, and the development of malignant tumors through immune regulation\u003csup\u003e[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]\u003c/sup\u003e. QI found that compared to procalcitonin (PCT), IL-6 at 2 hours postoperatively is the earliest and most valuable inflammatory marker for diagnosing postoperative urosepsis after percutaneous nephrolithotomy (PCNL)\u003csup\u003e[\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]\u003c/sup\u003e. Unfortunately, their study did not provide the optimal critical value for IL-6 at 2 hours postoperatively to further guide clinical treatment. Jia\u003csup\u003e[\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]\u003c/sup\u003eevaluated the diagnostic value of serum concentrations of CRP, PCT, and IL-6, and assessed whether their combined application is superior to individual use in diagnosing postoperative infections. The area under the curve (AUC) for CRP, PCT, and IL-6 in bacterial infections were 0.791, 0.859, and 0.783, respectively. The combination of CRP\u0026thinsp;+\u0026thinsp;PCT\u0026thinsp;+\u0026thinsp;IL-6 significantly improved the diagnostic efficiency of bacterial infections, with an AUC of 0.881. PCT, CRP, or IL-6 as single indicators have limited diagnostic value for predicting postoperative urinary tract infections (UTI) after flexible ureteroscopy (FURS), compared to the combined use of the three indicators. It is worth noting that these inflammatory markers are currently mainly used in the study of systemic inflammatory response syndrome (SIRS) after PCNL, and their effectiveness in early prediction of UTI after FURS needs further validation. Additionally, the critical values for each inflammatory marker vary slightly in different studies, which slightly limits their application in clinical practice. Therefore, future research is still needed to determine the optimal critical values for these inflammatory markers in different settings.\u003c/p\u003e \u003cp\u003eIn our study, renal dysfunction and ureteral stenosis are independent risk factors for UTI after surgery. When renal dysfunction occurs, the local and systemic defense mechanisms of patients change. The attachment of uropathogenic microorganisms to urothelial cells and the absorption of bacterial toxins into the blood initiate a complex process in the host. The release of various cytokines and mediator molecules, along with the activity of immune regulatory cells, influences the interstitial reaction of the upper and lower urinary tract and kidney. This leads to a decrease in body immunity and an increased risk of bacterial infection. Acute infection can affect the progression of preexisting renal disease. In cases of renal parenchymal damage or anatomical changes in the urinary tract, along with a deficiency in secretory IgA, Tamm-Horsfall glycoprotein, or other defense factors that protect the body's defense mechanism, renal function failure can be further exacerbated\u003csup\u003e[\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]\u003c/sup\u003e. Ureteral stricture is a frequent complication of ureteral calculi, which can result from laser thermal injury to the mucosal wall, stone entrapment, polyp encasement, and other strictures that may occur during ureteral surgery. Its further development may lead to renal and ureteral obstruction, renal function injury, and even renal failure. Hydronephrosis in the kidney and ureter leads to an increase in intrarenal pressure, causing bacteria attached to the urine and stone surfaces to be absorbed into the blood\u003csup\u003e[\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]\u003c/sup\u003e. The wrapping of polyps also diminishes the effectiveness of ESWL,FURL, and other procedures. The stones cannot be be broken, the remaining stones are trapped, and the urine containing bacteria cannot be drained smoothly, leading to further exacerbation of the infection.\u003c/p\u003e \u003cp\u003eOur study also has some limitations. The main limitations are the single-center, retrospective study and the relatively limited number of patients. The influencing factors of this study mainly involve the general clinical data and intraoperative conditions of patients, while ignoring some different intraoperative iatrogenic factors, such as the anesthesia mode of surgery, operating room temperature, intravenous infusion, and intraoperative infusion fluid absorption leading to the temperature change of patients, and the exposure of general anesthesia intubation. Additionally, the single-center data source of this study also has a certain impact on the reliability of the prediction model, and more validation data need to be obtained from other medical institutions. Therefore, more multicenter, large-sample prospective controlled studies are needed to verify the predictive validity and practicality of nomograms.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eRenal dysfunction, positive preoperative urine culture, positive urine nitrite, IL-6\u0026thinsp;\u0026gt;\u0026thinsp;5.3 pg/ml, uric acid\u0026thinsp;\u0026gt;\u0026thinsp;430 umol/l, and ureteral stenosis were identified as independent risk factors for UTI after FURL. The c-index and AUC of the nomogram prediction model constructed demonstrate that the prediction model exhibits good discrimination and accuracy. DCA shows that when the threshold is below 70%, this prediction model may provide net benefits for clinical intervention.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe author wish to thank the First Clinical Medical College of Three Gorges University and the Institute of Urology for their valuable assistance in this study\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatement of Ethics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study was approved by the Institutional Ethics Committee of the First Clinical Medical College of the China Three Gorges University. all patient information was obtained from the hospitalization system, All participants gave written informed consent before participating.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of Interest Statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding Sources\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo funding was received for this study\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eF.X. and X.C: contributed to the research ideas and design for study; F.X and Z.C.: Collected patient data and conducted analysis and organization; F.X, X.F and P.Z: Data analysis and model construction; F.X and H.Q: wrote and revised manuscript; X.C.: supervision or mentorship of manuscripts.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eLiu, Y,Chen, Y,Liao, B,Luo, D,Wang, K,Li, H, et al.(2018) Epidemiology of urolithiasis in Asia. \u003cem\u003eAsian J Urol 5\u003c/em\u003e (4), https://doi.org/10.1016/j.ajur.2018.08.007.\u003c/li\u003e\n\u003cli\u003eWollin, D A,Joyce, A D,Gupta, M,Wong, M Y C,Laguna, P,Gravas, S, et al.(2017) Antibiotic use and the prevention and management of infectious complications in stone disease. \u003cem\u003eWorld J Urol 35\u003c/em\u003e (9), https://doi.org/10.1007/s00345-017-2005-9.\u003c/li\u003e\n\u003cli\u003eVolkin, D.Shah, O.(2016) Complications of ureteroscopy for stone disease. \u003cem\u003eMinerva Urol Nefrol 68\u003c/em\u003e (6).\u003c/li\u003e\n\u003cli\u003eChugh, S,Pietropaolo, A,Montanari, E,Sarica, K.Somani, B K, (2020) Predictors of Urinary Infections and Urosepsis After Ureteroscopy for Stone Disease: a Systematic Review from EAU Section of Urolithiasis (EULIS). \u003cem\u003eCurr Urol Rep 21\u003c/em\u003e (4), https:// doi.org/10.1007/s11934-020-0969-2.\u003c/li\u003e\n\u003cli\u003ePeng, C,Li, J,Xu, G,Jin, J,Chen, J.Pan, S. 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cytokine: An overview of the immune regulation, immune dysregulation, and therapeutic approach. \u003cem\u003eInt Immunopharmacol 111\u003c/em\u003e, https://doi.org/10.1016/j.intimp.2022.109130.\u003c/li\u003e\n\u003cli\u003eQi, T,Lai, C,Li, Y,Chen, X.Jin, X, (2021) The predictive and diagnostic ability of IL-6 for postoperative urosepsis in patients undergoing percutaneous nephrolithotomy. \u003cem\u003eUrolithiasis 49\u003c/em\u003e (4), https://doi.org/10.1007/s00240-020-01237-z.\u003c/li\u003e\n\u003cli\u003eJia, W,Dou, W,Zeng, H,Wang, Q,Shi, P,Liu, J, et al.(2024) Diagnostic value of serum CRP, PCT and IL-6 in children with nephrotic syndrome complicated by infection: a single center retrospective study. \u003cem\u003ePediatr Res 95\u003c/em\u003e (3), https://doi.org/10.1038/s41390-023-02830-9.\u003c/li\u003e\n\u003cli\u003eKazan, H O,Cakici, M C,Efiloglu, O,Cicek, M,Yildirim, A.Atis, R G, (2020) Clinical characteristics of postoperative febrile urinary tract infections after ureteroscopic lithotripsy in diabetics: Impact of glycemic control. \u003cem\u003eArch Esp Urol 73\u003c/em\u003e (7).\u003c/li\u003e\n\u003cli\u003eBaboudjian, M,Gondran-Tellier, B,Abdallah, R,Tadrist, A,Sichez, P C,Akiki, A, et al.(2021) Single use and reusable flexible ureteroscopies for the treatment of urinary stones: A comparative study of perioperative complications. \u003cem\u003eProg Urol 31\u003c/em\u003e (6), https://doi.org/10.1016/j.purol.2020.11.014.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"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":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Flexible ureteroscope, Urinary tract infection, Fever, Predictive model","lastPublishedDoi":"10.21203/rs.3.rs-4183532/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4183532/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e \u003cp\u003eThe flexible ureteroscope offers advantages such as safety, minimally invasive procedures, quick recovery, and a high rate of stone removal. It has become a standard method for treating ureteral stones as well as small and medium-sized kidney stones. UTI is one of the most common postoperative complications that can lead to sepsis, systemic inflammatory response syndrome, urological sepsis, and even septic shock. Our aim is to analyze the risk factors for UTI following ureteroscopic lithotripsy and to develop corresponding clinical prediction models.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eA retrospective analysis was conducted on patients who underwent FURS surgery for urinary tract stones at our hospital from January 2021 to January 2023. Univariate and multivariate logistic regression analyses were used to identify independent risk factors for postoperative infection and to develop the corresponding Nomogram prediction model.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eIn total, 560 patients underwent flexible ureteroscopic lithotripsy (FURL) in our hospital, including 111 patients who developed postoperative UTI, resulting in an incidence rate of 19.8%. Analysis of the multivariate logistic regression data showed that renal dysfunction[OR\u0026thinsp;=\u0026thinsp;2.103(95%CI:1.134\u0026ndash;3.907),P\u0026thinsp;=\u0026thinsp;0.018],positive preoperative urine culture [OR\u0026thinsp;=\u0026thinsp;6.070(95%CI:1.800-20.474),P\u0026thinsp;=\u0026thinsp;0.004], positive urinary nitrate [OR\u0026thinsp;=\u0026thinsp;3.206 (95%CI: 1.599\u0026ndash;6.429),P\u0026thinsp;=\u0026thinsp;0.001],IL-6\u0026thinsp;\u0026gt;\u0026thinsp;5.3pg/ml[OR\u0026thinsp;=\u0026thinsp;6.876(95%CI:3.734\u0026ndash;12.661),P\u0026thinsp;\u0026lt;\u0026thinsp;0.001],uric acid\u0026thinsp;\u0026gt;\u0026thinsp;430 umol /L [OR\u0026thinsp;=\u0026thinsp;2.024(95%CI:1.088\u0026ndash;3.765),P\u0026thinsp;=\u0026thinsp;0.026], ureteral stricture[OR\u0026thinsp;=\u0026thinsp;3.174(95%CI:1.660\u0026ndash;6.070), P\u0026thinsp;\u0026lt;\u0026thinsp;0.001] were independent risk factors for UTI in patients after flexible ureteroscopy. The area under the ROC curve of the constructed nomogram prediction model is 0.89 (95% CI: 0.876\u0026ndash;0.937). The concordance index reached 0.841.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eRenal dysfunction, positive preoperative urine culture, positive urine nitrite, IL-6\u0026thinsp;\u0026gt;\u0026thinsp;5.3 pg/ml, uric acid\u0026thinsp;\u0026gt;\u0026thinsp;430 umol/L, and ureteral stenosis were identified as risk factors for UTI after flexible ureteroscopic lithotripsy. The nomogram prediction model has high clinical value in the prediction of UTI.\u003c/p\u003e","manuscriptTitle":"Risk factors analysis of Flexible Ureteroscopic Lithotripsy with UTI and construction of clinical prediction model","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-04-03 18:45:01","doi":"10.21203/rs.3.rs-4183532/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"80649451-8c15-46d4-b060-516d8aad5a20","owner":[],"postedDate":"April 3rd, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-04-03T18:45:03+00:00","versionOfRecord":[],"versionCreatedAt":"2024-04-03 18:45:01","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4183532","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4183532","identity":"rs-4183532","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}