Microbial distribution and antimicrobial resistance patterns of urinary tract infections in a specialized burn hospital in northern Iran: A six-year retrospective study

Urinary tract infections (UTIs) are an important healthcare-associated complication among hospitalized burn patients. However, the distribution of urinary pathogens and their antimicrobial susceptibility patterns may vary across burn-care settings. This study aimed to describe the microbial distribution and antimicrobial resistance patterns of UTIs among hospitalized burn patients. A retrospective observational study was conducted at Velayat Burn Injuries Hospital, northern Iran, including eligible burn patients with documented UTI and microbiological investigation between March 2021 and March 2026. Data were obtained from medical records, microbiology laboratory reports, and infection-control surveillance records. Demographic and clinical characteristics, hospitalization-related variables, urinary catheterization, bacterial isolates, and antimicrobial susceptibility results were reviewed. Only the first eligible UTI episode per patient during the hospitalization was included. Thirteen hospitalized burn patients with documented UTI were included. The mean age was 43.85 ± 15.10 years, and most patients were male, admitted to the intensive care unit, and had burns involving ≥30% of the total body surface area. Catheter-associated UTI (CAUTI) was documented in 5 patients (38.5%). Klebsiella spp. and Pseudomonas spp. were the predominant urinary isolates, each accounting for 46.2% of cases, whereas Escherichia coli accounted for 7.7%. Substantial resistance was observed among Pseudomonas and Klebsiella isolates to several commonly tested antimicrobial agents, particularly imipenem, piperacillin, and ceftazidime. Klebsiella spp. and Pseudomonas spp. were the predominant urinary pathogens identified in this specialized burn hospital, with considerable antimicrobial resistance among the recovered Gram-negative isolates. Continuous local microbiological surveillance and institution-specific susceptibility data may support appropriate empirical therapy, antimicrobial stewardship, and infection-prevention strategies in burn-care settings