title: Characteristics of epidemic and sporadic strains of Acinetobacter baumannii isolated in Abu Dhabi hospitals.
abstract: We compared the antibiotic susceptibility, clonal lineages and resistance genes of singleton Acinetobacter baumannii strains to those of isolates representing repeatedly encountered molecular types in five Abu Dhabi hospitals. One hundred and ten clinically relevant, non-repeat strains were typed by blaOXA-51-like allele sequencing and by PFGE, and selected isolates also by MLST. Resistance was assessed by MIC determinations and by disc diffusion. Genotyping was carried out by PCR, targeting 28 genes. The 80 epidemic strains belonged to worldwide lineages 1, 2 and 7, representing 11 pulsotypes and 9 genotypes, while the 30 sporadic isolates exhibited a high level of genetic variability and, with the exception of a small subgroup, were not associated with any recognized epidemic lineages. All epidemic subtypes carried the ISAba1-linked blaOXA-23 gene, and harboured the int, the blaPER and the armA genes significantly more frequently than their sporadic counterparts. They were all multi-drug resistant, including non-susceptibility to carbepenems, and were often extensively drug resistant, a phenomenon rarely seen among sporadic strains. Epidemic strains represented 78.8 % of intensive care unit isolates, causing more respiratory infections, while sporadic strains were more frequently isolated from wound and soft tissue infections. The study showed that among strains collected at the same time and from the same region, the very heterogeneous, sensitive sporadic strains, with the exception of a few non-susceptible singleton isolates, clearly differed from the highly resistant epidemic ones, which belonged to multiple pulsotypes and genotypes clustered into three worldwide clonal lineages carrying blaOXA-64, blaOXA-66 and blaOXA-69, respectively.
authors.affiliation: Department of Microbiology and Immunology, College of Medicine and Health Sciences, UAE University, Al Ain, UAE.
authors.forename: Ágnes
authors.initials: Á
authors.lastname: Sonnevend
authors.affiliation: Department of Microbiology and Immunology, College of Medicine and Health Sciences, UAE University, Al Ain, UAE.
authors.forename: Akela
authors.initials: A
authors.lastname: Ghazawi
authors.affiliation: Microbiology Laboratory, Al Rahba Hospital, Abu Dhabi, UAE.|Department of Microbiology and Immunology, College of Medicine and Health Sciences, UAE University, Al Ain, UAE.
authors.forename: Noura
authors.initials: N
authors.lastname: Al Munthari
authors.affiliation: Microbiology Laboratory, Sheikh Khalifa Medical City, UAE.
authors.forename: Martin
authors.initials: M
authors.lastname: Pitout
authors.affiliation: Microbiology Laboratory, Tawam Hospital, Al Ain, UAE.
authors.forename: Mohammad Baraa
authors.initials: MB
authors.lastname: Hamadeh
authors.affiliation: Department of Medicine, Tawam Hospital, Al Ain, UAE.
authors.forename: Rayhan
authors.initials: R
authors.lastname: Hashmey
authors.affiliation: Microbiology Laboratory, Mafraq Hospital, Abu Dhabi, UAE.
authors.forename: Safinaz Khaleel
authors.initials: SK
authors.lastname: Girgis
authors.affiliation: Microbiology Laboratory, Al Ain Hospital, Al Ain, UAE.
authors.forename: Farrukh Amin
authors.initials: FA
authors.lastname: Sheikh
authors.affiliation: Department of Microbiology and Immunology, College of Medicine and Health Sciences, UAE University, Al Ain, UAE.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Al Haj
authors.affiliation: Department of Microbiology and Immunology, College of Medicine and Health Sciences, UAE University, Al Ain, UAE.
authors.forename: Nico
authors.initials: N
authors.lastname: Nagelkerke
authors.affiliation: Department of Microbiology and Immunology, College of Medicine and Health Sciences, UAE University, Al Ain, UAE.
authors.forename: Tibor
authors.initials: T
authors.lastname: Pál
mesh_terms: D000151:Acinetobacter Infections / Q000382:microbiology*; D040981:Acinetobacter baumannii / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D005838:Genotype; D006761:Hospitals; D006801:Humans; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D058885:Multilocus Sequence Typing; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D014479:United Arab Emirates; D001618:beta-Lactamases / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D001618:beta-Lactamases; C577373:beta-lactamase OXA-51, Acinetobacter baumannii