Catheter-associated urinary tract infections in the intensive care setting: a five-year surveillance, microbiological and antibiotic-resistance study

Abstract Background Catheter-associated urinary tract infection (CAUTI) is among the most frequent healthcare-associated infections in intensive care units (ICUs) and an important driver of antimicrobial resistance. We described the incidence, microbiology, antibiotic-resistance profiles and factors associated with in-hospital mortality of CAUTI in the critical-care units of a training and research hospital. Methods In this retrospective cohort study of infection episodes, all CAUTI episodes identified through the national healthcare-associated infection surveillance network (which applies definitions adapted from the Centers for Disease Control and Prevention/National Healthcare Safety Network [CDC/NHSN] criteria) between 1 January 2021 and 31 December 2025 were analysed. Incidence was calculated per 1000 urinary-catheter-days using the surveillance denominator. Survivors and non-survivors were compared, and factors associated with in-hospital mortality were examined by Firth penalised-likelihood logistic regression; model discrimination was assessed by the area under the receiver-operating-characteristic curve (AUC). Results A total of 107 CAUTI episodes in 98 patients were analysed. The overall CAUTI incidence was 1.09 per 1000 urinary-catheter-days and the catheter utilisation ratio was 0.97. Of the isolates, 99.1% were Gram-negative; Klebsiella pneumoniae (40.2%), Acinetobacter baumannii (18.7%) and Pseudomonas aeruginosa (16.8%) predominated. Carbapenem resistance was extensive (K. pneumoniae 94–97%; A. baumannii ≥ 94%), whereas colistin, amikacin and ceftazidime-avibactam retained in-vitro activity against a proportion of isolates, although the number of isolates tested against some agents was small. In-hospital mortality was 65.1%. Impaired consciousness was independently associated with death (adjusted odds ratio 6.60, 95% confidence interval 2.25–19.39; p = 0.001); model discrimination was acceptable (AUC 0.769). Conclusions ICU-acquired CAUTIs were caused almost exclusively by multidrug-resistant Gram-negative bacteria and carried a high all-cause in-hospital mortality that tracked with critical-illness severity. Empirical therapy should be informed by local resistance data together with patient-level susceptibility testing, and catheter stewardship should be prioritised.