Risk Factors and Clinical Predictors of Urinary Tract Infections in Kidney Transplant Recipients: A Retrospective Single-Center Study.

Background

Urinary tract infections (UTIs) remain a significant complication following kidney transplantation (KT), contributing to morbidity and potential graft-related complications. This study investigates the incidence, risk factors, recurrence patterns, and multidrug-resistant (MDR) characteristics of UTIs in KT recipients.

Methods

A retrospective cohort study was performed, including 236 KT recipients transplanted between 2016 and 2023 at the University of Debrecen. Patients were classified according to UTI occurrence: 131 patients remained UTI-free, while 105 patients developed at least one microbiologically confirmed UTI. A total of 234 UTI episodes were analyzed, including 177 non-MDR and 57 MDR episodes. Clinical, donor-related, operative, viral, and immunosuppressive variables were evaluated. Univariate and multivariate logistic regression analyses were performed to identify independent predictors.

Results

UTIs occurred in 44.5% of recipients. Among 234 UTI episodes, 149 (63.7%) were recurrent and 57 (24.4%) were MDR. Patient-level risk factors associated with UTI occurrence included older age (P = .036), female sex (P < .001), higher Charlson Comorbidity Index (P = .040), and increased Kidney Donor Profile Index (P = .030). Prolonged hospitalization was independently associated with UTI occurrence and recurrence (P = .004 and P = .001, respectively). After multivariate adjustment, Extended-release calcineurin inhibitor formulations were independantly associated with reduced UTI occurrence and recurrence. Mycophenolic acid exposure was associated with increased UTI occurrence and MDR episodes in univariate analyses (P = .001 and P < .001, respectively), but no independent predictors of MDR infection were identified on multivariate analysis (P = .082).

Conclusions

UTIs remain a frequent complication following KT, with recurrent and MDR episodes representing a substantial proportion of infections. Recipient characteristics, donor factors, prolonged hospitalization, and immunosuppressive regimen characteristics contribute to infection risk. Optimization of perioperative management and immunosuppressive strategies may help reduce infectious morbidity, although prospective studies are required for validation.