Posttransplant biopsy risk for stable long-term pediatric liver transplant recipients: 451 percutaneous biopsies from two multicenter immunosuppression withdrawal trials.

Although liver biopsy is the gold standard for assessing allograft health, its attendant risk has deterred its use in routine monitoring of stable liver transplant recipients during long-term follow-up. We utilized prospectively collected data on adverse events from 2 clinical trials of immunosuppression withdrawal to quantify the risk of liver biopsy in pediatric liver transplant recipients. The trials included 451 liver biopsies in 179 children. No biopsies led to bleeding requiring transfusion or intervention, suggesting a clinically significant bleeding risk of <0.8%. Complications were reported in 5.5% of biopsies (95% CI 3.6%-8.1%): 5.8% (21/363) of protocol biopsies and 4.5% (4/88) of for-cause biopsies (P = .80). Mild complications occurred in 1.8% of biopsies, moderate in 1.8%, and severe in 2.0%. The majority of complications (89%) resolved within 1 week. Six of 9 (67%) severe complications were related to biliary issues; 5 were episodes of cholangitis. Biopsy-related cholangitis occurred only in children with underlying biliary strictures. Overall, biopsy-related complications were infrequent and resolved quickly. Severe complications were rare, with occult biliary stricture as the dominant driver. Our study provides evidence for clinicians who are considering the risk vs benefit of surveillance liver biopsies in pediatric liver transplant recipients.