Molecular characterization of clinical and environmental carbapenem resistant Acinetobacter baumannii isolates in a hospital of the Eastern Region of Saudi Arabia

Background: Environmental and clinical carbapenem-resistant Acinetobacter baumannii (CRAb) isolated in a hospital of the Eastern Region of Saudi Arabia were compared to assess the potential environmental contamination by this pathogen. Methods: Frequent-hand-touch surfaces of intensive care (ICU), medical (MW), and surgical (SW) units were randomly sampled for a month-long period, and the CRAb identified were compared to clinical isolates of the same period by PFGE and blaoxA_51_like gene sequencing. Carbapenemase and ribosomal methylase genes, ISAbal link to bla0)<A51-like or to blaoxA-23 respectively were detected by PCR. Results: CRAb was identified from 35.5% of surfaces. All environmental and clinical isolates were multior extremely drug resistant. PFGE of all clinical (n = 21) and selected environmental (n =30) isolates identified a singleton and four clusters, all of which included both clinical and environmental isolates. In the two largest clusters isolates carried blaoxA_66, ISAbal-linked blaoxA_23, and were from the ICU, MW and the male SW. Isolates of the female SW carried blaoxA_69, ISAbal-linked blaoxA_23 and blaGEs_11. A pair of clinical and environmental CRAb from the Male SW harboured blaNDmri in addition to ISAbal-linked bla0xA-94" Conclusion: A worrying level of environmental contamination, often by CRAb belonging to international clones, was revealed, highlighting the importance of environmental hygiene. (C) 2019 The Authors. Published by Elsevier Limited on behalf of King Saud Bin Abdulaziz University for Health Sciences.