Molecular characterization of beta-lactamase genes produced by community-acquired uropathogenic Escherichia coli in...

Extended-Spectrum Beta-Lactamases (ESBL) are a common mechanism of bacterial resistance in Enterobacteriaceae. The purpose of this study is to characterize the ESBL genes produced by community-acquired uropathogenic Escherichia coli strains in the Nouna District, in the West-African country, Burkina Faso.

Samples were collected from non-hospitalized patients who came for consultation at the CMA (Centre Médical avec Antenne chirurgicale) in Nouna and were sent to the laboratory for a urine culture test. The detection of ESBL production by the bacteria was carried out with the double-disc synergy test and the extraction of the ESBL genes with the heat shock method. Molecular characterization of ESBL genes was performed with three sequential multiplex polymerase chain reaction (PCR) assays.

One hundred and eighty-two (182) bacteriological cultures were analyzed and 29 E. coli isolated, between 01/07/2017 and 01/07/2018. The ESBL phenotype was found in 13/29 (44.8%). Multiplex PCR yielded many beta-lactamase genes, predominantly blaCTX-M-1,3,15 (12/13; 92.3%) followed by beta-lactamase genes blaOXA-1,4,30 (8/13; 61.5%) and beta-lactamase genes blaTEM-1,2 (7/13; 53.8%).

This study showed that the blaCTX-M-1,3,15 genes produced by uropathogenic E. coli were predominant. Sequencing of these genes would be needed to better characterize the different types of ESBL circulating in Nouna.