Emergence of B2-ST131-C2 and A-ST617 Escherichia coli clones producing both CTX-M-15- and CTX-M-27 and ST147 NDM-1 positive Klebsiella pneumoniae in the Tunisian community

Abstract

ABSTRACTCTX-M ESBLs have been increasingly reported from human enterobacteria isolates in Tunisia. NDM-1 carbapenemase was recently reported in isolates from Tunisian Hospitals. During a 2-month period (December 2017 to January 2018), we have collected 23 ESBL-producing Enterobacteriaceae (ESBL-E) from urines of patients hospitalized in three health care facilities and from community, situated in two distinct Tunisian geographical regions. They were divided into 15 Escherichia coli and eight Klebsiella pneumoniae. The aim of this study was to characterize ESBL-E with regard to their β-lactamase content and their epidemiological relationship. The results indicated a high rate (47%) of E. coli producing both CTX-M group-1 and −9. For the first time, we demonstrated the presence of E. coli having concomitantly CTX-M-15 and CTX-M-27 which belong to two sequences types (ST), ie. A-ST617 (2 isolates) and B2-ST131 subclade C2 (2 isolates). All four E. coli isolates carried a multireplicon IncF with an identical allelic combination, F31:A4:B1. This study reports also the first description of K. pneumoniae belonging to the clone ST147 carrying the carbapenemase NDM-1 in the Tunisian community. In conclusion, our data confirms the need for monitoring the resistance to extended-spectrum cephalosporins and to carbapenems among enterobacteria in Tunisia.