Characterization of the Genetic Supports for Betalactam Resistance in Escherichia coli Strains of Porcine Origin Producing Extended-spectrum Beta-Lactamase (ESBL)

Aims: The study was to evaluate the genetic potential of beta-lactam resistance in Escherichia coli strains producing extended-spectrum beta-lactamase (ESBL) isolated from the faecal flora of piglets.

Place and Duration of Study: National Reference Center for Antibiotics and Molecular Biology Platform of Pasteur Institute of Côte d'Ivoire, between June 2017 at July 2017.

Methodology: A detection of E. coli strains were carried out from 30 samples of faeces of piglets after five-day of treatment with amoxicillin was studied. The isolation of E. coli was performed on MacConkey agar supplemented with amoxicillin and identification using biochemical test. The Antibiotic susceptibility test was carried out according to diffusion method in agar medium.

Results: The genetic supports for betalactam resistance, in particular the bla TEM, bla SHV and bla CTX-Mgenes, have been detected by PCR in strains producing extended-spectrum beta-lactamase (ESBL). A total of thirty five (35) E. coli isolates (35%) showed ESBL production. The bla TEM, bla SHV and blaCTX-M genes were detected with frequency of 51%, 40% and 31% respectively. The strains were resistant to antibiotics from other families with the most common resistance profile consisting of tetracycline (100%), trimethoprim / sulfamethoxazole (80%), gentaminicin (70%), kanamycin (70%) and streptomycin (90%).

Conclusion: The detection of bla genes which are plasmid borne, therefore potentially horizontally transmissible to other strains, constitute a risk to public health and requires a monitoring of antibiotic-resistant bacteria in the animal production sector.