Microbiological profile, antimicrobial resistance patterns, and predictors of mortality in ventilator-associated pneumonia in a respiratory intensive care unit: a prospective study

Abstract

Introduction
Among critically ill patients, ventilator-associated pneumonia (VAP) continues to play a significant role in adverse outcomes, including increased morbidity and mortality, particularly in the era of increasing antimicrobial resistance.


Objective
To identify the microbiological profile, antimicrobial susceptibility patterns, and resistance phenotypes of pathogens causing VAP in a respiratory intensive care unit (RICU), and to assess determinants of mortality.


Methodology
A prospective observational study was undertaken in (RICU), Chest Diseases and Tuberculosis Department, from the period from April 2023 to October 2025. Eighty-seven patients diagnosed with (VAP) were included in the study, and clinical parameters were evaluated according to survival outcomes.


Results
Among the studied patients, overall 45 patients (51.7%) were survivors, whereas 42 patients (48.3%) died. Non-survivors had higher prior healthcare exposure, including previous hospitalization (54.8% vs 33.3%) and ICU admission/mechanical ventilation (52.4% vs 24.4%). Gram-negative organisms predominated (85.5%), mainly Klebsiella (46.8%) and Acinetobacter (29.8%). XDR pathogens were more common in non-survivors (54.8% vs 15.6%), whereas MDR predominated in survivors (75.6% vs 38.1%). Mortality was associated with higher APACHE II scores (23.45 ± 5.73 vs 15.64 ± 4.25) and presence of septic shock (59.5% vs 26.7%).


Conclusion
Mortality among VAP patients was associated significantly with higher APACHE II scores and a higher incidence of septic shock in non-survivors. Additionally, extensively drug-resistant (XDR) pathogens were more prevalent among non-survivors, illustrating the contribution of antimicrobial resistance and clinical severity to patient outcomes.