AmpC ß-lactamases in SE Asian Enterobacterales

Clinical isolates, collected between 2010 and 2020, of Escherichia coli and Klebsiella pneumoniae from Laos, Cambodia and Thailand were retrospectively investigated for AmpC production using MASTDISCS (AmpC, ESBL and Carbapenemase Detection Set - D72C) and whole genome sequencing. By MASTDISC testing, 31/130 (23.8%) isolates were AmpC positive and 17 (13.1%) were inducible AmpC positive. Whole genome sequencing was performed for a total of 76 isolates, and revealed multiple sequence types associated with AmpC/Inducible AmpC phenotypes (ST131 and ST410 were most common), in addition to identifying associated chromosomal and plasmid mediated resistance genes (including blaCMY-2, blaCMY-6, blaCMY-42, and blaDHA-1 genes).