High Rates of Carbapenem Resistance Among Respiratory Pathogens in ICU Patients: A Single-Centre Study in Iran
Novelty in Biomedicine,
Vol. 14 No. 3 (2026),
25 August 2026
,
Page 120-126
https://doi.org/10.22037/nbm.v14i3.51822
Abstract
Background: Respiratory tract infections are a leading cause of morbidity among hospitalized patients, with antimicrobial resistance increasingly complicating treatment decisions. This study aimed to determine the distribution and antimicrobial resistance patterns of respiratory pathogens isolated from intensive care unit (ICU) patients at a tertiary care hospital in Tehran, Iran.
Materials and Methods: This retrospective cross-sectional study analyzed sputum samples collected between April 1, 2024 and March 1, 2025, at a tertiary care hospital in Tehran, Iran. Bacterial identification and antimicrobial susceptibility testing were performed using standard microbiological methods according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Data were analyzed using SPSS version 26.
Results: A total of 114 ICU patients were included, with a mean age of 74.5 years. Gram-negative bacteria predominated (85.1%), with the most common pathogens being Acinetobacter baumannii (50 isolates, 43.9%), Klebsiella pneumoniae (26 isolates, 22.8%), and Pseudomonas aeruginosa (16 isolates, 14.0%). A. baumannii exhibited 100% resistance to imipenem, meropenem, ceftriaxone, and ciprofloxacin, with 95.7% resistance to amikacin and 97.1% to ceftazidime. K. pneumoniae showed 91.7% resistance to imipenem, 100% to ceftriaxone, ciprofloxacin, and aztreonam, and 64.0% resistance to amikacin. P. aeruginosa demonstrated 87.5% resistance to imipenem and ciprofloxacin, 83.3% to ceftazidime, and 50.0% to amikacin. Colistin remained active against 97-100% of isolates across all three pathogens.
Conclusion: This study documents high levels of antimicrobial resistance among the predominant respiratory pathogens, particularly A. baumannii and K. pneumoniae, with carbapenem and cephalosporin resistance exceeding 90% in most cases. These findings highlight the urgent need for robust antimicrobial stewardship programs, enhanced infection control measures, and continuous surveillance to preserve remaining therapeutic options and prevent further spread of resistant organisms in hospital settings.
- Antimicrobial resistance
- Acinetobacter baumannii
- Klebsiella pneumoniae
- Pseudomonas aeruginosa
- multidrug resistance
- Iran
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References
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