Ventilator Associated Pneumonia by Acinetobacter baumannii And antimicrobial susceptibility pattern

Background: Ventilator Associated Pneumonia (VAP) is one of the serious complications of ventilator support occurring in ICUs. The aim of this study was to determine the susceptibility pattern of Acinetobacter baumannii (A. baumannii) isolated from patients with VAP by two methods: disk diffusion and E. test. Methods: This descriptive-cross sectional study was conducted in the four ICUs of Rasoul-e-Akram Hospital in Tehran, from October 2016 to November 2017. A total of 58 endobronchial aspirates from intubated patients who had been clinically diagnosed to have VAP by A. baumannii were studied. The in vitro susceptibility was determined by disk-diffusion and broth microdilution MIC methods. The results were used in chi2 assay to express a meaningful relationship. P<0.05 was considered statistically significant. Results: With the E. test method high percentage of isolates were resistant to levofloxacin (100%), carbapenems (meropenem: 93.10%, imipenem 70.69%), piperacillin-tazobactam (50%) and aminoglycosides (gentamicin 41.38%). The most sensitive antibiotic was colistin. Conclusion: Antimicrobial resistance to A. baumannii in ICUs is increasing, and the findings of the study have shown that colistin is the only drug with relative efficacy.