Restricted accessResearch articleFirst published online 2026-2
Evaluation of the Antimicrobial Resistance Pattern and Distribution of Strains Isolated from Adult Patients with Lower Respiratory Tract Infection at a Tertiary Care Hospital in Western Turkey
Hospital-acquired respiratory infections caused by antimicrobial-resistant bacteria have become a major public health problem worldwide. This study aimed to evaluate the distribution and antimicrobial resistance profiles of bacterial strains isolated from adult patients treated with a diagnosis of lower respiratory tract infection in our hospital.
Materials and Methods:
Respiratory tract samples of adult patients hospitalized in our hospital were included. The identification of the isolated strains and their antibiotic susceptibilities were studied by the PHOENIX 100 (Becton Dickinson, USA) automated system, and results were evaluated according to the European Committee on Antimicrobial Susceptibility Testing criteria.
Discussion and Conclusions:
In this study, we observed that Gram-negative bacteria were more common than Gram-positive bacteria in lower respiratory tract samples. The multidrug resistance rate in Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii isolates is detected as 59%, 12.9%, and 96.4%, respectively. Carbapenem resistance rates for K. pneumoniae (n = 261), A. baumannii (n = 250), and P. aeruginosa (n = 132) were 88.9%, 97.2%, and 43.2%, respectively. The multidrug resistance and carbapenem resistance rates detected in lower respiratory tract samples in our study are alarming. It is noteworthy that the resistance rates we found are higher than the rates reported in other studies conducted in our country.
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