Development of a Kidney Transplant‐Specific DOOR for Urinary Tract Infections Assessing the Impact of Carbapenem Resistance

BACKGROUND: Urinary tract infections (UTIs) in kidney transplant (KT) recipients are frequent and associated with increased morbidity and mortality. Traditional outcome measures may underestimate its true clinical burden. The Desirability of Outcome Ranking (DOOR), developed by the Antibacterial Resistance Leadership Group, is a patient-centered composite outcome designed to capture the full spectrum of infectious complications. METHODS: We refined the DOOR framework for complicated UTIs by incorporating transplant-specific variables and evaluated its application in a cohort of KT recipients with UTIs between 2013 and 2023. RESULTS: Ninety-seven patients with carbapenem-resistant (CR) UTIs were matched 1:1 by infection year to patients with carbapenem-susceptible (CS) infections. Compared with the standard cUTI DOOR, the KT-UTI DOOR reclassified 41 patients to worse outcome ranks. Using the KT-UTI DOOR, the probability of a more favorable outcome in CR versus CS infections was 41.3% (95% CI: 34.2%-48.7%, p = 0.02) in the unadjusted analysis and 43.4% (95% CI: 36.2%-50.9%, p = 0.08) after adjustment. Transplant-related complications were the only events independently associated with CR infections. In contrast, using the established cUTI DOOR, the corresponding probability was 45.8% (95% CI: 38.8%-52.9%, p = 0.24) in the adjusted analysis. CONCLUSION: Incorporating transplant-related variables improves the clinical relevance of DOOR in KT recipients.