Fosfomycin Resistant Enterobacterales IsolatedFrom Chicken Meat in Turkey

Résumé 0

This study was conducted to obtain the relative prevalence of fosfomycin resistant (FOSr) Enterobacterales in raw chicken meat samples in Turkey. Samples (n=85) were enriched in non-selective media and transferred to MacConkey agar plates containing FOS and glucose-6-phosphate. As a result, FOSr Enterobacterales isolates were detected by a selective method in 27% of raw chicken meat samples (n=23) and identified as Escherichia coli (21/26), Klebsiella oxytoca (2/26), Escherichia vulneris (1/26), Raoultella terrigena (1/26) and Kluyvera intermedia (1/26). PFGE analysis showed 16 different band patterns in Escherichia spp. isolates (n=22) based on the 85% similarity. The minimum inhibitory concentration for FOS against all isolates was determined to be ≥64 mg/L. In addition, the highest rate of resistance was determined for nalidixic acid (72.7%), ampicillin (68.2%), tetracycline (59.1%), trimethoprim-sulfamethoxazole (54.5%), and chloramphenicol (59.1%) among all Escherichia isolates. PCR screening and sequencing identified the presence of fosA4 and fosA3 genes in ten (47.6%) and seven (33.3%) E. coli isolates, respectively. The fosA3 gene has also appeared in K. intermedia, and R. terrigena isolates.  Only two E. coli isolates were positive for the blaCTX-M-55 gene, whereas the aac(6')-Ib-cr gene was identified in eight E. coli and one K. intermedia isolates. In addition, 19 different replicon types were determined by PCR-based plasmid replicon typing with IncFII (n=20) being the most common and followed by IncI1α (n=10), IncFIIS (n=8), and IncFIB (n=8). We report, to our knowledge, the first evidence on the presence of FOSr Enterobacterales isolates in raw chicken meat samples in Turkey that might be an important reservoir for FOSr organisms to humans.