High Prevalence of Multidrug-Resistant Escherichia coli in Urine Samples from Inpatients and Outpatients at a...

The worldwide dissemination of multidrug-resistant (MDR) Enterobacteriaceae is a major public health issue. The aim of this study was to investigate the prevalence of MDR Escherichia coli (MDR-EC) isolates, in inpatients/outpatients with urinary tract infections at Sétif University Hospital (Algeria). Bacterial cultures were obtained from 426 of the 3,944 urine samples collected from January 2015 to February 2017. Among these cultures, 215 E. coli isolates were identified by mass spectrometry, and 38 (17.7%) were MDR-EC (disk diffusion method): 36 produced only extended-spectrum β-lactamases (ESBL), one ESBL and a carbapenemase, and one only a cephalosporinase (double-disk synergy test). Multiplex PCR and sequencing analyses showed that 37 ESBL-producing isolates harbored genes encoding CTX-M enzymes (CTX-M-15 in 33 isolates, 89.19%; and CTX-M-14 group in four isolates, 10.81%). One CTX-M-15-producing isolate co-expressed also an OXA-48-like carbapenemase. Phylogenetic group analysis of the 37 ESBL-producing and 178 non-ESBL-producing isolates indicated that the most common phylogenetic group was B2 (54.05% of ESBL-producing and 48.31% of non-ESBL-producing isolates), followed by A and D for ESBL-, and by B1, A, and F for non-ESBL-producing isolates. This is the first report highlighting the presence of MDR-EC isolates that produce both CTX-M and OXA-48-like enzymes in Sétif, Algeria.