Significance and safety evaluation of renal biopsy in patients with diabetic nephropathy

Objective:It is a common condition that diabetic nephropathy (DN) coincides with other non-diabetic renal disease. The renal biopsy should be necessary for diagnozing a patient with atypical feature. However,the optimal timing of observation and the safety after biopsy is not well established. The aim of this study was to investigate the significance and safety of renal biopsy in patients with DN. Methodology:A prospective observation was performed in one hundred and eleven cases with type 2 diabetes who received percutaneous renal biopsy. The complications were evaluated at 4 h,8 h,24 h,48 h and 72 h after biopsy by monitoring gross hematuria,flank pain,hypotension,hemoglobin and renal ultrasound examination. Results:We observed that 28 cases (25.2%) of biopsies complicated with hematoma. The size of hematoma was between 2-4 cm2 in 20 cases (18.0%),and 8 cases was larger than 4 cm2 (7.21%). There were 3 cases with symptomatic hematoma (2.7%). Among the 8 cases with large hematoma,3 cases with renal failure (SCr 114.9-152.9 μmol/L),and other 3 cases were coincidence with IgA nephropathy and membranoproliferative glomerulonephritis. The timing of large hematoma peaked in 4 h. We found that 11 cases (9.91%) had gross hematuria. Among them,4 cases with renal dysfunction (SCr 166.2-265.2 μmol/L) and other 5 cases were coincidence with IgA nephropathy and microscopic polyangitis. The hematoma and gross hematuria improved spontaneously without further intervention. In renal pathological diagnosis,there were 31 cases (27.9%) with nondiabetic renal disease including 20 cases of IgA nephropathy,8 membranous nephropathy,one membranoproliferative glomerulonephritis,one amyloidosis and one microscopic polyangitis. Conclusion:The main complications of renal biopsy in patients with DN were hematoma and gross hematuria. They mostly occurred within 8hrs,especially in 4hrs,and might improved spontaneously without intervention. DN patients with renal dysfunction,increased frequency of puncture and coincidence with IgA nephropathy and systemic vasculitis were risk factors after biopsy. To ensure the safety of the biopsy,the key point is to control the indication exactly,have a full examination before the operation,and improve the operative technique. In DN patients,renal biopsy is necessary for making diagnosis and treatment.