Ureteral stent placement and BK viremia in kidney transplant recipients

Introduction BK virus (BKV) infection is an important cause of kidney transplant dysfunction. A possible association of double-J ureteral stent placement and BK viremia has been suggested in previous studies; however, risk factors for BK are incompletely understood. We aimed to determine if stent placement is an independent risk factor for BK viremia. Methods Data were collected on consecutive kidney-only transplant recipients between December 1, 2006 and June 30, 2010. All patients had at least 12months of follow-up. Results Of 600 consecutive kidney transplants, BK viremia within the first post-transplant year was detected in 93 patients (15.5%); in 70 of these cases, the peak BKV polymerase chain reaction was 10,000 copies/mL. By multivariate analysis, significant risk factors for BK viremia were recipient age (P=0.02) and stent placement (P=0.03). Stents were placed in 49.2% and removed at a median of 46days (range: 11284) post transplantation; removals occurred within 030, 3060, 6090, 90120, 120150, and >150days post transplantation in 18.4%, 67.2%, 10.5%, 2.4%, 1.0%, and 0.3% of cases, respectively. No association was found of BK viremia with stent duration >46days (P=0.70) or by the 6-level groupings (P=0.92). Conclusions Although we observed a significant association of BK viremia with stent placement, no dose-dependent effect was seen.