Prevalence of Extensively and Pan-drug-resistant Acinetobacter spp. in Nosocomial Infections in Western Saudi Arabia

Abstract

Multidrug resistance patterns of Acinetobacter spp. have led to their emergence as an important source of nosocomial infections. This study investigated the prevalence and clinical characteristics of Acinetobacter spp. in hospital-acquired wound and urinary tract infections. A total of 432 samples [wound swabs (210) and urine samples (222)] were analyzed for the presence of Acinetobacter spp. through selective culturing on MacConkey and Leeds Acinetobacter medium followed by identification with API 20E strips and Vitek 2 compact system. Antimicrobial susceptibility was assessed by adopting the disk diffusion method on Muller-Hinton agar, whereas the minimum inhibitory concentration procedure was carried out by using a ComASP™ Colistin test kit. Biofilm formation was examined using microtiter plates and following the crystal violet staining method. PCR was performed to amplify virulence (lasB, bap, and plcN) and antimicrobial resistance (blaOXA-51like) genes. The results revealed a low prevalence of Acinetobacter spp. (1.85 %) where Acinetobacter baumannii was the predominant species. Acinetobacter baumannii isolates harbored blaOXA-51-like gene to exert extensive or pan-drug resistance. Most Acinetobacter baumannii isolates demonstrated weaker to moderate biofilm-forming capabilities and carried the bap gene. Acinetobacter baumannii isolates lacked the combination of virulence factors encoding lasB and plcN genes. Acinetobacter baumannii infections are rising in Saudi Arabia. The results of this study highlight the epidemiology of virulent and antibiotic-resistant Acinetobacter spp., particularly A. baumannii, in Saudi Arabia. The detailed elaboration on the diversity, virulence, and antimicrobial susceptibility patterns of Acinetobacter spp. in Saudi Arabia requires further in-depth molecular investigations.