Study of the Antibiotic Resistance Pattern of Bacteria Causing Ventilator-Associated Pneumonia in Al-Zahra Hospital, Isfahan

Abstract

Background: Ventilator-associated pneumonia (VAP) is one of the most common nosocomial infections in intensive care units that is highly resistant to common antibiotics. In this regard, this study was conducted with the aim of identifying common pathogens causing pneumonia and risk factors associated with multidrug resistance in Al-Zahra Hospital, Isfahan. Methods: In this cross-sectional study, the records and endotracheal culture results of 100 patients with ventilatorassociated pneumonia who were hospitalized in the inpatient and intensive care units of Al-Zahra Hospital were reviewed. Microbial agents were divided into two groups with multidrug resistance (PDR-MDR-XDR) and susceptible and were analyzed along with demographic information and risk factors. Findings: Of the 170 pathogens identified, 27 were PDR (15.8), 75 were MDR (44.2), 45 were XDR (26.5), and 23 were susceptible (13.5). The most common microbes were Acinetobacter (40.5) and Klebsiella pneumoniae (43.5), and the lowest resistance rates of these two bacteria were related to the antibiotics colistin and amikacin. The most common pathogens in the intensive care unit were Acinetobacter (32.7) and Klebsiella (35.6). There was no significant difference between risk factors such as age, gender, and hospitalization department with the rate of antibiotic resistance. The rate of multidrug resistance was higher in surgical diseases (P = 0.043), cardiac diseases (P = 0.049), and cancers (P = 0.035). Conclusion: The results showed that Acinetobacter and Klebsiella pneumoniae are the dominant pathogens in pneumonia and have high resistance to antibiotics. To reduce this resistance, it is necessary to implement infection control programs and rational prescription of antibiotics. This study emphasizes the need for continuous monitoring of antibiotic resistance patterns and the development of effective treatment protocols. © 2026, Isfahan University of Medical Sciences(IUMS). All rights reserved.