Infection and Drug Resistance (Oct 2019)
Characterization of phenotypic and genotypic traits of carbapenem-resistant Acinetobacter baumannii clinical isolates recovered from a tertiary care hospital in Taif, Saudi Arabia
Abstract
Mohamed F El-Badawy,1,2 Sayed F Abdelwahab,1,3 Saleh A Alghamdi,4 Mohamed M Shohayeb1,5 1Division of Pharmaceutical Microbiology, Department of Pharmaceutics and Industrial Pharmacy, College of Pharmacy, Taif University, Taif 21974, Kingdom of Saudi Arabia; 2Department of Microbiology and Immunology, Faculty of Pharmacy, Misr University for Science and Technology, 6th of October City 12568, Egypt; 3Department of Microbiology and Immunology, Faculty of Medicine, Minia University, Minia 61511, Egypt; 4Medical Genetics, Clinical Laboratory Department, College of Applied Medical Sciences, Taif University, Taif 21974, Kingdom of Saudi Arabia; 5Department of Microbiology and Biotechnology, Faculty of Pharmacy, Delta University for Science and Technology, Gamasa 35712, EgyptCorrespondence: Mohamed M ShohayebDivision of Pharmaceutical Microbiology, Department of Pharmaceutics and Industrial Pharmacy, College of Pharmacy, Taif University, Taif 21974, Kingdom of Saudi ArabiaTel +20 106 147 9097Email [email protected] and objective: Acinetobacter baumannii (A. baumannii) is a common nosocomial pathogen, which developed multi-drug-resistance to different classes of antibiotics including carbapenems. This study examined ten common carbapenemase genes among 32 carbapenem-resistant A. baumannii clinical isolates recovered from Taif, Saudi Arabia.Methods: Isolates were phenotypically identified to the genus level by Vitek®2 and API 20NE®. The species level was confirmed by the amplification of blaOXA-51. The susceptibility for 21 different antibiotics was performed by Vitek 2 and modified Kirby-Bauer method. Isolates were genetically screened for 10 carbapenemases. Phylogenetic relatedness between isolates was determined by ERIC-PCR.Results: Genotypically identified A. baumannii represented 100% of the total phenotypically identified Acinetobacter spp. All the carbapenem-resistant isolates were sensitive to polymyxin B and colistin. Among the other antibiotics, ampicillin/sulbactam and tigecycline were the most effective agents. 90.8% of the isolates were resistant to all ten investigated β–lactams. blaOXA-51, blaIPM, blaNDM and blaOXA-23 were detected in 100%, 87.5%, 62.5% and 59.4% of isolates, respectively. Also, blaVIM and blaOXA-40 were less prevalent and were detected in 9.3% and 3.1% of the isolates, respectively. In addition, blaKPC, blaOXA-48, blaOXA-58, blaOXA-181 were not detected in any isolate. The A. baumannii isolates were categorised into ten genotypes on the basis of the detected carbapenemase genes and ERIC-PCR revealed a remarkable clonal diversity among these isolates.Conclusion: Class A and class D carbapenemase genes were the most commonly detected among carbapenem resistant A. baumannii (CRAB) clinical isolates.Keywords: A. baumannii, blaOXA-51, carbapenemases, carbapenems, ERIC-PCR
