Fecal carriage of extended-spectrum β-lactamase-producing Enterobacteriaceae in community setting in Casablanca

Background: The importance of community-acquired infections due to extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) has been increasingly recognized in recent years. This study aimed to determine the prevalence of intestinal carriage of ESBL-PE in the community in Casablanca, Morocco. Methods: During 6 months (2013), 93 fecal samples were examined for ESBL-PE. Isolates expressing an ESBL phenotype were investigated for the presence of genes encoding beta-lactamases and plasmid-mediated quinolone resistance. Conjugation experiments were done to determine the mobility of ESBL genes. Results: The prevalence of fecal carriage of ESBL-PE was 4.3% (4/93; 95% CI, 0.2-8.4). Klebsiella pneumoniae (n = 2), Enterobacter cloacae (n = 2), Escherichia coli (n = 1), and Serratia odorifera (n = 1) were the ESBL-producing species. Four (66.7%) of these isolates were multidrug-resistant. The bla(SHV-12) (n = 5) was the most frequent ESBL gene detected, followed by bla(CTX-M-15) (n = 3). The non-ESBL gene detected was bla(TEM-1) (n = 5). One isolate harbored the qnrB1 variant. Results of conjugation experiments indicated that bla(SHV-12) + bla(TEM-1) + qnrB1 and bla(CTX-M-15) + bla(TEM-1) genes were co-transferred and that these genes were carried by a conjugative plasmid of high molecular weight (125 kb). Conclusion: Our results show the importance of the intestinal tract as a reservoir for ESBL-PE in the community in Morocco.