Rapid identification of carbapenemase-type blaGES and ESBL-type blaGES using multiplex PCR.

Guiana extended-spectrum (GES) β-lactamases are emerging in Japan. The GES family can be classified into 2 groups, one with extended-spectrum β-lactamase (ESBL)-like activity, which hydrolyzes penicillins and cephalosporins, and the other with carbapenemase-like activity with an extended spectrum toward carbapenems. This difference is mediated by variations in a specific amino acid in the GES protein: G170 N or G170S substitutions. We developed an amplification refractory mutation system (ARMS) PCR assay that enabled rapid identification of these variant genes without sequencing.