Ureteral stent duration and the risk of BK polyomavirus viremia or bacteriuria after kidney transplantation

ObjectivesUreteral stents are used in kidney transplantation (KTX) to decrease post-operative complications, but they are associated with BK polyomavirus viremia (BKV). Our primary outcome was to determine the association between ureteral stent duration and BKV. Secondary outcome measures were the association between bacteriuria and stent duration or use of ureteral stent strings. MethodsBetween January 2010 and January 2015, 403 patients underwent KTX at the Virginia Mason Medical Center and met inclusion criteria. Stent duration was classified as short (<3weeks) or long (>3weeks). Multivariate logistic regression models were created to assess for factors associated with BKV. The covariates in the BKV model were chosen a priori based on stent duration and risk factors previously described in the literature. ResultsUreteral stents were placed in 304 (75.4%) transplants. Stent strings were left attached in 166 (54.6%) patients. On multivariate analyses, long stent duration was significantly associated with increased risk of BKV compared with no stent (odds ratio [OR] 1.92, P=.044, 95% confidence interval [CI] 1.04-3.74). Short stent duration was not associated with BKV. Sixty-two (15.4%) patients had bacteriuria. Bacteriuria was associated with female gender (OR 2.77, P<.001, 95% CI 1.58-4.95), and there was a dose-dependent effect with stent duration compared with no stentshort duration (OR 2.46, P=.049, 95% CI 1.05-6.49) and long duration (OR 3.58, P=.004, 95% CI 1.58-9.25). Stent strings were not associated with either complication. ConclusionsThe association between ureteral stents and BKV may be dose dependent.