Genetic diversity of OXA-51-like genes among multidrug-resistant Acinetobacter baumannii in Riyadh, Saudi Arabia

• Published in: European journal of clinical microbiology & infectious diseases Vol. 33; no. 7; pp. 1223 - 1228
• Main Authors: Aly, M., Tayeb, H. T., Al Johani, S. M., Alyamani, E. J., Aldughaishem, F., Alabdulkarim, I., Balkhy, H. H.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.07.2014; Springer; Springer Nature B.V
• Subjects: Acinetobacter baumannii; Acinetobacter baumannii - classification; Acinetobacter baumannii - drug effects; Acinetobacter baumannii - enzymology; Acinetobacter baumannii - isolation & purification; Acinetobacter Infections - epidemiology; Acinetobacter Infections - microbiology; beta-Lactamases - classification; beta-Lactamases - genetics; Biological and medical sciences; Biomedical and Life Sciences; Biomedicine; DNA, Bacterial - chemistry; DNA, Bacterial - genetics; Drug Resistance, Multiple, Bacterial; Gene amplification; Genetic diversity; Genetic Variation; Genotype; Humans; Infectious diseases; Inpatients; Internal Medicine; Medical Microbiology; Medical sciences; Multilocus Sequence Typing; Polymerase Chain Reaction; Prevalence; RNA polymerase; Saudi Arabia - epidemiology; Saudi Arabia; Asia; Riyadh Saudi Arabia; Gulf Cooperation Council; Carbapenem Resistance; Acinetobacter Baumannii; Multilocus Sequence Typing; tnpA; Infection; Acinetobacter baumannii; Microbiology; Multiple resistance; Neisseriaceae; Molecular epidemiology; Bacteria; Micrococcales; Genetic diversity
• ISSN: 0934-9723; 1435-4373
• DOI: 10.1007/s10096-014-2068-0

We explore the genetic diversity of class D oxacillinases, including OXA-23, -24 (-40), -58 and, particularly, the intrinsic OXA-51-like genes, among multidrug-resistant (MDR) Acinetobacter baumannii strains from inpatients at a tertiary care hospital in Riyadh, Saudi Arabia. Sequence-based typing (SBT) of the OXA-51-like gene was carried out on 253 isolates. Selected isolates ( n  = 66) were subjected to multilocus sequence typing (MLST). The polymerase chain reaction (PCR) typing results showed that all isolates ( n  = 253) contained the OXA-51-like and OXA-23 genes. However, the OXA-58 gene was detected in five isolates. Further, none of the isolates had the OXA-40 (identical to the OXA-24) gene. SBT revealed a high OXA-51-like genotypic diversity and showed that all isolates were clustered into four main groups: OXA-66 (62.3 %), followed by OXA-69 (19.1 %), OXA-132 (7.6 %) and other OXA-51-like genes (10.3 %), including OXA-79, -82, -92, -131 and -197. MLST revealed four main sequence types (STs), 2, 19, 20 and 25, among the isolates, in addition to six isolates with newly designated ST194–ST197 singletons. Further, a high prevalence (81.4 %) of OXA-66 and OXA-69-like genes in A. baumannii was identified. More studies are essential in order to explore the molecular mechanisms that confer carbapenem-resistant phenotypes for A. baumannii isolates and to investigate the genetic diversity of other OXA-D genes.