Study of fluoroquinolones resistance genes in Acinetobacter baumannii isolated from clinical sources

Abstract

Acinetobacter baumannii is a common multidrug-resistant bacteria that causes hospital-acquired illnesses. This research attempted to identify quinolone resistance genes in A. baumannii isolated from various clinical materials, including burns, blood, sputum, urine, and diabetic foot infections, with a distribution of 199 (53%) male and 176 (47%) female subjects. The bacterial culture results indicated that out of 375 specimens, 157 (41.9%) exhibited single growth, 28 (7.4%) displayed mixed growth, and 190 (50.7%) showed no bacterial growth.  This study identified 155 instances (41.33%) of gram-negative bacteria. The Vitek-2 system identified 28 isolates (7.46%) as A. baumannii. The highest isolation rate occurred in burn patients at 17 (4.53%), followed by 4 (1.07%) isolates from patients with respiratory tract infections, and 3 (0.8%) from blood source records. Diabetic foot infections and urinary tract infections were documented in two instances (0.53%). The antimicrobial susceptibility test results revealed that all 28 (100%) isolates demonstrated resistance to Cefoxitine, Ceftazidime, and Ciprofloxacin. Additionally, 27 (96.42%) of the isolates were resistant to meropenem, while 26 (92.85%) exhibited resistance to tobramycin and Ampicillin-Sulbactam. Concurrently, 89.28% of the isolates were resistant to gentamicin. The PCR analysis results indicated that the qnrA, qnrB, and qnrS genes were identified in 11 (39%), 7 (25%), and 21 (75%) of the A. baumannii isolates, respectively.