Study of occurrence of Multidrug Resistant Escherichia coli Clinical isolates as a result of Extended Spectrum Beta-Lactamase (Esbls) Production

Abstract

Resistance to antibiotics by microorganisms has increased dramatically in the past few years. Resistance to third-generation cephalosporins and other classes of antibiotics is attributed to the production of beta-lactamase genes located on mobile genetic elements, which facilitate their transfer between different species. This study was undertaken to determine the presence of ESBLs in 400 isolates of Escherichia coli obtained from various clinical specimens (urine, stool, blood, wound swabs, sputum and throat swabs) collected from 216 female and 184 male patients attending various health facilities in Makurdi, Benue State, Nigeria; and to relate ESBL production with antibiotic resistance. Antibiotic susceptibility test using penicillin, ceftriaxone, ceftazidime, cefuroxime, cefotaxime, amoxicillin and clavulanic acid, gentamycin, chloramphenicol and imipenem antibiotic discs sourced from OXOID, USA was carried out, using NCCLS guidelines on the isolates. The presence of ESBLs was determined using the Double Disc Synergy (DDST) test. The isolates showed the highest resistance to penicillin 392(98%) producing 62(15.8%) ESBLs. Only 8 (2%) isolates were susceptible to penicillin. This was closely followed by resistance to ceftriaxone (385; 96.3%), producing 62(16.1%) ESBLs. The isolates were also resistant to other classes of antibiotics:  aminoglycosides (gentamycin) 331(82.7%), carbapenem, imipenem 2(0.5%) which was the least. Three hundred and ninety-eight (99.5%) of the isolates were susceptible to imipenem. Isolates from blood specimens (26.3%; n=5) harboured the highest percentage of ESBLs, followed by isolates from wound swab specimens (17.3%; n=9). The study showed moderate production of ESBLs resulting in multiple antibiotic resistance.