RESUMO
BACKGROUND: Extended spectrum beta-lactamase (ESBL) has been described in Escherichia coli strains that have been isolated from humans and animals; it has induced a main concern with antibiotic resistance in serious bacterial infections. AIMS: This study aimed to investigate the frequency of ESBL-producing E. coli (EPE) strains in meat and intestinal contents of turkey, and to compare the antibiotic resistance profile between EPE and non-EPE strains. METHODS: Totally, 70 and 110 E. coli strains were isolated from turkey meat and turkey intestinal content samples, respectively. To determine EPE strains, double disc synergy test was applied by that 20 and 22 EPE strains were finally identified in meats and intestinal contents of the turkeys, respectively. Antibiotic susceptibility was exerted using disc diffusion method. Escherichia coli isolates were then characterized for virulence genes (stx-1 and stx-2) and ESBL genes (TEM, SHV, and CTX-M). RESULTS: None of the E. coli strains harbored stx genes. The EPE strains in comparison with non-EPE strains were significantly more resistant to ciprofloxacin (47.6 vs 26.5%), tetracycline (80.9 vs 67.3%), ampicillin (47.6 vs 22.4%), penicillin (23.8 vs 10.2%), ceftazidime (57.1 vs 16.3%), ceftriaxone (38.1 vs 18.4%), and cefotaxime (47.6 vs 8.2%). The majority of EPE strains carried CTX-M gene. SHV showed the lowest frequency and it was not detected in EPE strains isolated from the intestinal contents. In this study, 75% of TEM-producing E. coli strains and 33% of SHV-producing E. coli strains were resistant to ampicillin. In addition, 41.7% of TEM-producing E. coli strains were resistant to penicillin, and 76.9% of CTX-producing E. coli were resistant to cefotaxime. Furthermore, 4.7% of EPE strains isolated from turkey meat were imipenem resistant. CONCLUSION: The resistance to cefotaxime and imipenem in EPE strains induces a concern in growing antibiotic resistance against broad spectrum antibiotics in E. coli strains.
RESUMO
BACKGROUND: Pet birds have close contact to human and resistant bacteria can transfer from birds to intestinal flora of human. AIMS: This study was carried out to determine the tetracycline resistance genes in Escherichia coli strains associated with enteric problem in pet birds. METHODS: Totally, 295 cloacal swabs were collected from 195 healthy and 100 diarrheic pet birds in Isfahan province, Iran. The presence of E. coli was identified by conventional bacteriological, biochemical, and molecular examinations. The presence of tetracycline resistance genes (tetA, tetB, tetC, tetD, tetE, tetG, tetK, tetL, tetM, tetO, and tetS genes) were examined using three multiplex PCR. RESULTS: The results showed that 18.9% and 43% of cloacal samples of healthy and diarrheic pet birds contained E. coli, respectively. The mean percentage of E. coli isolated from cloacal samples of diarrheic birds was significantly higher than the healthy birds (46.6 vs 23.1%). In healthy birds, out of 37 E. coli isolates, 10 isolates were resistant to tetracycline, harboring tetA and tetB genes (3 tetA vs 7 tetB), but in the diarrheic birds, of 26 resistance E. coli, 11, 12, and 3 strains contained tetA (42.3%), tetB (46.15), and tetA+tetB (11.53%) genes. The percentage of tet genes were significantly higher in diarrheic birds than healthy birds (58.9 vs 24.0%). CONCLUSION: Both resistant genes of tetA and tetB were detected in E. coli isolates that are related with efflux pump activity. These genes can be transferred between Gram-negative bacteria and they have the potential ability to be transferred to the environment and human flora.