Percutaneous Ultrasound-Guided Kidney Transplant Biopsy Outcomes: From the Nephrologist to the Radiologist Standpoint.

Background: Kidney transplant biopsies are the gold standard for evaluating allograft dysfunction. These biopsies are performed by nephrologists and radiologists under real-time ultrasound guidance. A few studies have examined the outcomes of ultrasound-guided kidney transplant biopsy in transplant recipients; however, none have compared these outcomes between both specialties. Methods: We retrospectively analyzed a cohort of 678 biopsies performed in a single center during a 44-month study period. Biopsies were stratified into two groups based upon the specialist performing the procedure: interventional radiology (IR; N=447) and transplant nephrology (TN; N=231). Results: There were 55 (8%) complications related to biopsies in the entire cohort: 37 (8.2%) in the IR group and 18 (7.7%) in the TN group, without statistical difference between the groups (P=0.94). Blood pressure control and prior use of anticoagulation were significant predictors of complicated biopsies (P=0.004 and 0.02, respectively). Being a woman and prior use of anticoagulation were significant predictors of transfusion of blood products (P=0.01 and 0.01, respectively). Being a woman and blood pressure control were significant predictors of overall perinephric hematoma (P=0.01 and 0.01, respectively), and Black race was a significant predictor of perinephric hematoma without worsening of renal function (P=0.005). The specialist team performing the procedure was not a statistically significant predictor of biopsy complications, transfusion of blood products, or perinephric hematoma with comparable sample yield. Conclusions: Percutaneous ultrasound-guided kidney transplant biopsy performed by transplant nephrologists have similar complication rates when compared with interventional radiologists in an academic center.