Investigation of the Characteristics of Multidrug-Resistant (MDR) Acinetobacter Baumannii Lytic Phage Isolated from the Intensive Care Unit

Abstract

Background: The aim of this study was to isolate, characterize, and investigate the efficacy of specific phages against multidrug resistant (MDR) Acinetobacter baumannii to use them as an appropriate and effective method to replace antibiotic treatment, or be used as an antiseptic for the hospital surfaces. Methods: In a cross-sectional study in a period of two years (2017-2019), 48 suspected Acinetobacter baumannii strains were isolated from patients admitted to the intensive care unit (ICU) in Alzahra hospital, Isfahan, Iran. First, the isolates were identified by phenotypic method, and confirmed with blaOXA-51 gene amplification. Then, the antibiotic sensitivity of isolates was assessed using disk diffusion method, and the isolation of phage from water sources was carried out. Finally, the sensitivity of Acinetobacter baumannii isolates, and different hosts to phage were investigated, and One-Step Growth Curve was detected. Findings: All Acinetobacter baumannii isolates were confirmed, and the pattern of antibiotic resistance percentage was 99% to ciprofloxacin, 96% to ceftazidime, 97% to cefipime, 82% to amikacin, and 100% to imipenem. The specific phage was isolated from the sewage, 27 isolates of Acinetobacter bumannii were sensitive to phage, and other different hosts were not affected by the phages. Finally, after 30 minutes in the latent phase, phage was exploded during a period of 40 minutes. Conclusion: According to the results of the effectiveness of phage in disturbing Acinetobacter baumanni, and considering the increasing rate of the resistance of it to most of the antibiotics and the difficulty of treating its infections, phage therapy can be used as a therapeutic approach for this infection.

Keywords

• Acinetobacter baumannii
• Multidrug resistance
• Bacteriophages
• Phage therapy