Search

• 228 carbapenem-resistant Acinetobacter baumannii (CRAB) strains were collected from 29 laboratories in 10 countries. • bla OXA-72 -associated plasmid co-harbouring bla NDM-1 was found in four isolates from Serbia. • High diversity of the K locus was found in CRAB strains from Serbia, Turkey and Greece. Multi-drug-resistant Acinetobacter baumannii isolates are key pathogens that contribute to the global burden of antimicrobial resistance. This study aimed to investigate the phenotypic and molecular characteristics of carbapenem-resistant A. baumannii (CRAB) isolates from the EURECA clinical trial. In total, 228 CRAB clinical strains were recovered from 29 sites in 10 European countries participating in the EURECA study between May 2016 and November 2018. All strains were reconfirmed centrally for identification and antimicrobial susceptibility testing, and were then subjected to DNA isolation and whole-genome sequencing (WGS), with analysis performed using BacPipe v.1.2.6. K and O typing was performed using KAPTIVE. Overall, 226 (99.1%) strains were confirmed as CRAB isolates. The minimum inhibitory concentration (MIC 90) results of imipenem and meropenem were >16 mg/L. WGS showed that the isolates mainly harboured bla OXA-23 (n =153, 67.7%) or bla OXA-72 (n =70, 30.1%). Four bla OXA-72 isolates from Serbia co-harboured bla NDM-1. An IS 5 transposase family element, IS Aba31 , was found upstream of the bla OXA-72 gene harboured on a small (~10-kb) pSE41030-EUR plasmid. The majority of isolates (n =178, 79.1%) belonged to international clone II. Strains belonging to the same sequence type but isolated in different countries or within the same country could be delineated in different clusters by core-genome multi-locus sequence typing (MLST). Whole-genome/core-genome MLST showed high diversity among the isolates, and the most common sequence type was ST2 (n =153, 67.7%). The EURECA A. baumannii strain collection represents a unique, diverse repository of carbapenem-resistant isolates that adds to the existing knowledge of A. baumannii epidemiology and resistance genes harboured by these strains. [ABSTRACT FROM AUTHOR]