Changes in Respiratory Microorganism Distribution and Antimicrobial Resistance Patterns in Intensive Care Units: A Comparative Analysis Before and During the COVID-19 Pandemic
Abstract
This study aimed to evaluate changes in the distribution of microorganisms isolated from respiratory tract specimens and antimicrobial resistance patterns in intensive care units (ICUs) before and during the COVID-19 pandemic. Microbiological data from respiratory tract specimens obtained from patients admitted to the ICUs of a state hospital between January 1, 2019, and April 30, 2021, were retrospectively reviewed. The study period was divided into the pre-pandemic period (January 1, 2019–February 29, 2020) and the pandemic period (March 1, 2020–April 30, 2021). A total of 634 patients and 757 respiratory tract isolates were included. The median age was 79 years (IQR: 66–85), and 55.2% of the patients were male. Acinetobacter spp. was the most frequently isolated microorganism overall, followed by Klebsiella spp., Pseudomonas spp., Escherichia coli, and Staphylococcus aureus. Overall microorganism distribution differed significantly between the pre-pandemic and pandemic periods (p<0.001). Antimicrobial resistance analyses were performed for the most frequently isolated bacterial pathogens. No significant changes were observed in resistance rates among Pseudomonas spp. isolates. Among Acinetobacter spp. isolates, trimethoprim-sulfamethoxazole resistance increased significantly during the pandemic period. Among Klebsiella spp. isolates, trimethoprim-sulfamethoxazole resistance increased significantly. These findings indicate that the COVID-19 pandemic period was associated with changes in respiratory microorganism distribution and selected antimicrobial resistance patterns in ICUs.
Keywords
- COVID-19
- intensive care unit
- respiratory tract specimens
- antimicrobial resistance
- Acinetobacter spp.
- Klebsiella spp.
- Pseudomonas spp.
Supporting Institution
Project Number
Ethical Statement
Thanks
References
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Details
Primary Language
English
Subjects
Clinical Sciences (Other)
Journal Section
Research Article
Authors
Gülsüm Kaya
*
0000-0003-2517-5512
Türkiye
Burcu Gürer Giray
0000-0003-3165-8924
Türkiye
Didem Özgür
0000-0002-8320-9453
Türkiye
Sinem Solmaz
0009-0006-9367-4566
Türkiye
Mehtap Oskay
0000-0002-7287-3631
Türkiye
Ece Yilmaz Erbay
0009-0007-8047-7587
Türkiye
Şeyma Trabzon
0000-0001-9030-7804
Türkiye
Hasan Ergenç
0000-0003-0519-0264
Türkiye
Sebahat Aksaray
0000-0002-0552-1337
Türkiye
Publication Date
November 4, 2026
Submission Date
June 16, 2026
Acceptance Date
September 27, 2026
Published in Issue
Year 2026 Volume: 52