Distribution Profile of Extended Spectrum Beta Lactamase (ESBL) producing Escherichia coli Isolates from Asa River (Nigeria)

Abstract

Escherichia coli are known pathogenic organism that has caused diseases which has led to severe morbidity and increased death rate. The occurrence of extended spectrum beta Lactamase (bla) producing Escherichia coli has been on the rise. Water samples were investigated as a potential reservoir for the Extended Spectrum Beta- Lactamase (ESBL) - producing E. coli using phenotypic (culture-based) and molecular methods. Double disc synergy test was determined between a disc of amoxicillin-clavulanate (20μg/10μg) (augmentin) and a 30-μg disc of each  thirdgeneration cephalosporin antibiotic placed at a distance of 20 mm from centre to centre on a Mueller-Hinton Agar plate streaked with the isolate. An isolate was considered to be ESBL negative if there was no enhancement between any of the cephalosporin and the clavulanate-containing discs and were then subjected to specific Polymerase Chain Reaction (PCR). Eighty-four environmental E. coli was isolated. 58(69.04%) showed positivity for ESBL production. E. coli isolates positive for ESBL-production selected and subjected to plasmid curing were all plasmid mediated. 16 isolates subjected to PCR to identify the presence of blaSHV (Sulphydryl Variable), blaTEM (Temoneira) and blaCTX-M  (Cefotaximase) genes revealed that 11(68.7%) of these had at least one ESBL gene (either blaCTX-M or blaTEM, or both), 5(31.3%) isolates do not have any of the three ESBL genes, and blaSHV was not detected in any of the isolates. The results of this study indicate the widespread prevalence of ESBLs in E. coli. Therefore, beta-lactam antibiotics and beta-lactamase inhibitors should be prescribed based on an antibacterial susceptibility test.

Keywords: WATER, E. coli, ESBL, DDST, PLASMID CURING and ASA RIVER