Pediatric renal biopsy: should this procedure be performed in an outpatient setting?

Although several retrospective reports suggest that pediatric outpatient renal biopsies may be done in a safe and cost-effective manner, risk factors and the natural history of major complications following this procedure have not been clearly delineated. In an effort to determine the minimal observation period required to detect major post-renal biopsy complications in children and to establish clinical parameters predictive of these complications, a retrospective review of 177 percutaneous renal biopsies was performed. The overall major complication rate was 3.4%, while the minor complication rate was 14.1%. The mean percentage change in hemoglobin 4-10 h postbiopsy in patients with major bleeding complications was significantly greater than patients with minor bleeding complications. Using a 16% drop in hemoglobin 4-10 h postbiopsy, the sensitivity and specificity of identifying a major bleeding complication was 100% and 98%, respectively, while the positive and negative predictive value was 68% and 100%, respectively. All patients with major complications due to excess sedation or immediate bleeding were diagnosed within 11 h of the biopsy. Automated renal biopsies offered several safety and efficiency advantages compared with non-automated methods. Our results suggest that outpatient pediatric renal biopsies should be encouraged provided certain precautions are taken to reduce the risk of developing major complications.