Effects of Receiving Renal Biopsy on the Prognosis of Chronic Kidney Disease Patients with Impaired Renal Function

Background: Impaired renal function was not a recognized indication for renal biopsy. The effects of receiving renal biopsy on the renal functional prognosis for chronic kidney disease (CKD) patients with impaired renal function need to be explored. Methods: : This study retrospectively enrolled 300 renal function impaired CKD patients in Renji Hospital from January 2015 to December 2017, 150 of them received percutaneous renal biopsy while the others did not. The endpoint was ≥50% estimated glomerular filtration rate (eGFR) decline from baseline or development of end-stage renal disease (ESRD). Kaplan-Meier analysis with log-rank test was performed to compare the renal survival probability between patients receiving renal biopsy or not. Univariate and multivariate analysis with Cox regression were conducted with predictors of poor renal outcomes in the study cohort. Results: : The median follow-up period was 37.6 months. During the follow-up period, the eGFR of the biopsy group increased from 52.2±14.4 to 67.4±37.8 ml/min/1.73m², but decreased from 55.3±17.1 to 29.8±19.1 ml/min/1.73m² in the non-biopsy group. Patients who received renal biopsy had significantly higher renal survival probability (P<0.001). Cox regression analysis revealed that 24-hour urine protein excretion (24h UPE) more than 1g/d was an independent predictor for poor renal outcomes in the non-biopsy group but not in the renal biopsy group (HR=1.719, P=0.040). Conclusion: CKD patients with impaired renal function are recommended to receive renal biopsy to make pathological diagnoses, especially for those with the 24-hour urine protein excretion more than 1g/d.