Drug-Resistant Infections in Burn Patients: A One-Year Analysis of Microbiological Trends and Predictive Risk Factors in a Romanian Tertiary Care Centre

Background and Objectives: The susceptibility of burn patients to infections with multidrug-resistant organisms (MDROs) is high. The aim of this study is to describe the local patterns of antimicrobial resistance in a Romanian burn unit and to identify risk factors associated with the acquisition of extensively drug-resistant (XDR) pathogens. Materials and Methods: We conducted a one-year, observational, retrospective single-centre cohort study including all burn patients with at least one positive culture admitted to our unit during 2024. In order to identify the pathogens and perform antibiograms, we used routine microbiological diagnostic tests. A multivariable logistic regression model was used to identify XDR risk factors. We also compiled a cumulative antibiogram using the first non-duplicate isolate per patient, following the CLSI M39 guidelines. Results: Among the 180 total admissions, 128 (71.1%) had at least one positive microbiological culture, resulting in 643 bacterial isolates out of 559 samples. The most frequently identified species were A. baumannii, P. aeruginosa, S. aureus, and K. pneumoniae. We isolated MDROs in 59.37% of patients, and 26.56% had at least one XDR pathogen isolated during hospitalisation. We identified three independent predictors for the isolation of XDR pathogens: a higher Abbreviated Burn Severity Index (ABSI) score (aOR 6.12; p = 0.001), hospital length of stay (LOS) (aOR 1.02; p = 0.030), and the number of bacterial species identified per sample, representing polymicrobial growth (aOR 5.91; p = 0.001). Conclusions: Our findings highlight a significant percentage of MDR and XDR pathogens and provide the foundation for antimicrobial stewardship measures, using the local cumulative antibiogram for empirical therapy.