Objective: This study aimed to investigate the prevalence and genetic relatedness of multidrug-resistant Gram-negative bacilli, particularly those resistant to carbapenems, in patients admitted to intensive care units. It also sought to explore associations between bacterial colonization or infection and clinical outcomes, including comorbidities, treatment regimens, and mortality.
Methods: Between November 2022 and December 2023, screening and pathological samples were collected from patients at a tertiary hospital. Screening samples included rectal and pharyngeal swabs, while pathological samples comprised respiratory tract secretions. Bacterial identification and antibiotic susceptibility testing were performed using standard microbiological methods. Genetic similarity among isolates was assessed using a molecular fingerprinting technique to detect potential clonal spread.
Results: A total of 62 carbapenem-resistant strains were identified, with Acinetobacter baumannii and Klebsiella pneumoniae being the most prevalent. Pathological isolates exhibited higher resistance levels than screening isolates. Most patients had multiple comorbidities, with cardiac, renal, and pulmonary conditions being the most common. A significant association was found between prolonged intensive care unit stay and increased mortality. However, no significant correlation was observed between the number of comorbidities or antibiotic classes used and mortality. Molecular analysis revealed clonal clusters of Acinetobacter and Klebsiella strains, suggesting nosocomial transmission.
Conclusions: The findings underscore the importance of early screening, molecular surveillance, and stringent infection control measures in intensive care settings.