Prevalence and antimicrobial susceptibilities of Acinetobacter baumannii and non-baumannii Acinetobacters from Terengganu, Malaysia and their carriage of carbapenemase genes

Abstract

A total of 153 non-repeat Acinetobacter spp. clinical isolates obtained in 2015 from Hospital Sultanah Nur Zahirah (HSNZ) in Terengganu, Malaysia, were characterized. Identification of the isolates at species level was performed by ribosomal DNA restriction analysis (ARDRA) followed by sequencing of the rpoB gene. The majority of the isolates (n=128; 83.7 %) were A. baumannii while the rest were identified as A. nosocomialis (n=16), A. calcoaceticus (n=5), A. soli (n=2), A. berezeniae (n=1) and A. variabilis (n=1). Multidrug resistance (MDR) was most prevalent in A. baumannnii (66.4 %) whereas only one non-baumannii isolate (A. nosocomialis) was MDR. The blaOXA-23 gene was the predominant acquired carbapenemase gene (56.2 %) and was significantly associated (P<0.001) with carbapenem resistance. However, no significant association was found for carbapenem resistance and isolates that contained the ISAba1-blaOXA-51 configuration.

Keywords: Acinetobacter baumannii; beta-lactamases; carbapenem resistance; multidrug resistance; non-baumannii Acinetobacter.