1:30 PM Abstract No. 206 - Surveillance protocol transplant renal biopsy: assessment of safety in 549 cases at a tertiary care transplantation center

Abstract

Purpose Renal transplant surveillance biopsy performed at fixed time points after kidney transplantation is aimed at detecting subclinical graft rejection prior to overt manifestation as serum creatinine elevation. While these scheduled biopsies may provide a histologic basis for adjusting immunosuppressive regimens, they subject patients to intrinsic risk associated with invasive tissue sampling. This study was undertaken to assess the safety of a surveillance protocol transplant renal biopsy program at an urban tertiary care transplantation center. Materials and Methods In this single institution retrospective study, 399 patients underwent extraperitoneal renal transplant surveillance biopsy between January 2010 and October 2012. In general, biopsies were performed 1, 3, 6, and 12 months post-transplant, and annually thereafter. 18-gauge samples were obtained using direct sonographic guidance, with 3-4 needle passes made in each case with on-site pathologic assessment of tissue adequacy. Medical record review was used to identify procedure-related complications, which were graded according to the Society of Interventional Radiology classification of complications. Results 549 renal transplant surveillance biopsies were performed during the study period. Procedure-related complications occurred in 7/549 (1.3%) cases, and included 1 minor complication and 6 major complications. The minor complication consisted of transient post-biopsy hematuria. Major complications included 4 peri-nephric hematomas (1 requiring percutaneous drainage, 1 requiring operative evacuation, and 1 resulting in compressive renal failure), 1 case of hematuria requiring prolonged hospitalization, and 1 arteriovenous fistula requiring embolization. There were no patient deaths. Conclusion Surveillance renal transplant biopsy may be performed with a high degree of safety. Future studies should aim to weigh the low but non-zero overall complication rate against the frequency of detected subclinical graft rejection requiring immunosuppressive medication modification.