Prevalence Study of Aminoglycoside-Resistance Genes in Acinetobacter Baumannii Isolated from the Patients in Intensive Care Unit

Background: Acinetobacter baumanniii is a highly antibiotic-resistant nosocomial opportunistic pathogen possess. This study aimed to assess the antibiotic-resistance pattern and detect the molecular frequency of aphA6 and aadB genes in Acinetobacter baumannii isolated from patients in intensive care unit (ICU). Methods: In this cross-sectional study, 58 Acinetobacter baumannii isolates collected from ICU patients in Imam Reza hospital, Kermanshah, Iran, were confirmed using standard bacteriological tests. Disc diffusion method was deployed for screening resistant isolates. The prevalence of aphA6 and aadB genes was assessed using polymerase chain reaction (PCR) method with specific primers. Findings: The highest antibiotic resistance rates were seen in ticarcilin (87.9%) and ceftazidime (86.2%) and the lowest was of polymyxin B (12.1%). Of 58 Acinetobacter isolates, 36 (62.1%) and 9 (15.5%) harbored aphA6 and aadB genes, respectively. In addition, 5 isolates (8.6%) harbored both genes and 18 isolates (31.3%) were negative for any of those genes. Conclusion: 80% of Acinetobacter isolates showed resistance to aminoglycoside antibiotics. Considering the high rates of antibiotic resistance to this category and other investigated antibiotics in this study, it seems necessary to precise on the use of antibiotics such as polymyxin B to treat the infections caused by this pathogen.