Presence of Extended-Spectrum β-Lactamases Genes in E. coli Isolated from Farm Workers in the South of London

Abstract

Sixty - four isolates of E. coli were isolated from urine, stool, and skin samples of farm workers in south of London. Antibiotic susceptibilities were tested by using the agar dilution protocol by using amikacin, ampicillin, aztreonam, meropenem, cefotaxime, ceftazidime, ceftriaxone, ciprofloxacin, gentamycin, imipenem, ofloxacin, and cefpodoxime. Determination of ESBL of E. coli isolates was performed according to CLSI by using two discs method. PCR was used to detect of CTX-M, TEM, and SHV genes and genotyped E. coli isolates which were reported as ESBL producers in both two disks and E-test methods. The results illustrated that thirty-eight isolates (n=64, 59 %) had multi drug resistance, and the resistance results recorded as the follows; imipenem (0%), meropenem (0%), ofloxacin (7%), ciprofloxacin (10%), ampicillin (89%), cefpodoxime (86%), aztreonam (82%), gentamycin (70%), ceftriaxone (31%), ceftazidime (37%), cefotaxime (62%), and amikacin (65%). Twelve of E. coli isolates (n=64, 18.7%) were phenotypically ESBL producers. eleven isolated of ESBL phenotype-positive E. coli carried bla genes (n=12, 91.7 %), blaCTX-M was found in eleven isolates (91.6 %), blaTEM in eight isolates (66.6 %), and blaSHV in one isolate (8.3 %).