Independent risk factors for urinary tract infection and for subsequent bacteremia or acute cellular rejection: a single-center report of 1166 kidney allograft recipients.

Background: Urinary tract infection (UTI) is a frequent, serious complication in kidney allograft recipients.
Methods: We reviewed the records of 1166 kidney allograft recipients who received their allografts at our institution between January 2005 and December 2010 and determined the incidence of UTI during the first 3 months after transplantation (early UTI). We used Cox proportional hazards models to determine the risk factors for early UTI and whether early UTI was an independent risk factor for subsequent bacteremia or acute cellular rejection (ACR).
Results: UTI, defined as 10 or more bacterial colony-forming units/mL urine, developed in 247 (21%) of the 1166 recipients. Independent risk factors for the first episode of UTI were female gender (hazard ratio [HR], 2.9; 95% confidence intervals [CI], 2.2-3.7; P<0.001), prolonged use of Foley catheter (HR, 3.9; 95% CI, 2.8-5.4; P <0.001), ureteral stent (HR, 1.4; 95% CI, 1.1-1.8; P=0.01), age (HR, 1.1; 95% CI, 1.0-1.2; P=0.03), and delayed graft function (HR, 1.4; 95% CI, 1.0-1.9; P=0.06). Trimethoprim/sulfamethoxazole prophylaxis was associated with a reduced risk of UTI (HR, 0.6; 95% CI, 0.3-0.9; P=0.02). UTI was an independent risk factor for subsequent bacteremia (HR, 2.4; 95% CI, 1.2-4.8; P=0.01). Untreated UTI, but not treated UTI, was associated with an increased risk of ACR (HR, 2.8; 95% CI, 1.3-6.2; P=0.01).
Conclusions: Female gender, prolonged use of Foley catheter, ureteral stent, age, and delayed graft function are independent risk factors for early UTI. UTI is independently associated with the development of bacteremia, and untreated UTI is associated with subsequent ACR.