Original Article

Burden and resistance of Gram-negative pathogens in ICU-acquired infections in Vietnam: a cross-sectional study

Abstract

Background and Objectives: This study aimed to describe the burden, pathogen distribution, antimicrobial resistance patterns, and selected clinical outcomes of intensive care unit (ICU)-acquired Gram-negative bacteria (GNB) infections in Vietnam, with exploratory comparative analyses of outcomes.
Materials and Methods: A retrospective descriptive study with comparative analyses was conducted among 102 adult patients with culture-confirmed ICU-acquired GNB infections at E Hospital, Hanoi. Demographic, clinical, microbiological, and outcome data were extracted from medical records. Antimicrobial susceptibility testing was performed according to Clinical and Laboratory Standards Institute guidelines. Comparisons between outcome groups were assessed using chi-square test, with effect sizes quantified using Cramer’s V.
Results: Pneumonia was the predominant infection (70.5%), followed by urinary tract (15.2%) and bloodstream infections (10.6%). GNB accounted for 68.3% of all hospital-acquired infections (HAIs), with Acinetobacter baumannii (43.4%), Pseudomonas aeruginosa (24.8%), and Klebsiella pneumoniae (13.9%) being the most frequent pathogens. The predominant pathogens exhibited extensive resistance to β-lactams, cephalosporins, and carbapenems. Susceptibility was largely retained only to colistin, tigecycline, and amikacin. Mechanical ventilation was significantly associated with death or a severe clinical outcome (p = 0.03; Cramer’s V = 0.21).
Conclusion: GNB dominate ICU-acquired infections in Vietnam and demonstrate alarming antimicrobial resistance, underscoring the urgent need for strengthened infection control and antimicrobial stewardship.

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IssueVol 18 No 1 (2026) QRcode
SectionOriginal Article(s)
DOI https://doi.org/10.18502/ijm.v18i1.20904
Keywords
Hospital-acquired infection Gram-negative bacteria Drug resistance Microbial Intensive care units Pneumonia Ventilator-associated Antimicrobial stewardship
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How to Cite
1.
Phong D, Vinh V, Van D, Hieu T, Huong T, Thuong L, Duc L, Huong N. Burden and resistance of Gram-negative pathogens in ICU-acquired infections in Vietnam: a cross-sectional study. Iran J Microbiol. 2026;18(1):32-40.