Background: Although infectious complications are the second most common cause of death after transplantation, there appears to be insufficient data regarding the impact of urinary tract infections (UTIs) on graft outcome and patient mortality and morbidity. In this study, we evaluated the incidence, risk factors, and long-term effects of UTIs on graft function.
Method: We performed a retrospective cohort study reviewing the medical records of patients who received a renal transplant at our center from January 1999 to December 2006. All UTIs, risk factors, long-term graft function, graft loss, and death were recorded. Outcomes among patients with UTIs were compared with those without UTIs.
Results: Fifty-six of 136 patients (41.2%) had at least one UTI over a mean period of 38+/-25 months after transplantation. While there was a tendency toward graft loss among patients with UTIs (16.1% vs 6.3%, P=.08), there was no increased risk of death. The patients with UTIs displayed higher serum creatinine levels (1.7+/-1.4 vs 2.3+/-2.5 mg/dL, P=.07) compared to non-UTI patients in the long term. Upon multivariate analysis, female gender was the only risk factor for posttransplant UTIs. We did not determine any immunosuppressive drug as a risk factor for UTIs. The most frequent pathogens isolated in urine culture were Escherichia coli (n=72, 59.1%) and Klebsiella spp (n=21, 16.9%), and there were eight cases of bacteremia.
Conclusion: UTIs are a frequent problem after kidney transplantation. Female recipients are at greatest risk. In the long-term, UTIs should be considered as a potential risk for poorer graft outcomes.