摘要

肠外大肠杆菌由于其作为机会致病菌的扩散而成为全球性威胁，并且最重要的是它们广泛的抗生素抗性决定因素。尽管食用动物已经被判定用于将多重耐药细菌传播给人类的载体，但我们对其起源和传播途径的了解仍然存在许多差距。该研究分析了从巴勒莫的零售商店购买的46个肉类样本，以获得喹诺酮类抗生素的大肠杆菌分离株。筛选菌株的系统发育组，ST131相关的单核苷酸多态性（SNP），然后通过ERIC-PCR分型。研究了它们的毒力因子，即kpsMII，papA，sfaS，focG，iutA，papC，hlyD和afa基因，并评估了它们的氟喹诺酮抗性决定因子。获得的数据显示巴勒莫地区多药耐药模式的流行率非常高，28％的分离株具有典型的ExPEC菌株的毒力因子基因。未检测到B2组或ST131菌株。此外，我们的分离株中有20％显示出对所有质粒介导的喹诺酮类抗生素（PMQR）决定簇的阳性，显示出将这些基因转移到其他细菌中的潜力。因此，这些数据强调了食用动物，特别是特别是家禽可能是抗性细菌菌株的重要来源的可能性，从而构成潜在的人畜共患风险。

Extra-intestinal E. coli are emerging as a global threat due to their diffusion as opportunistic pathogens and, above all, to their wide set of antibiotic resistance determinants. There are still many gaps in our knowledge of their origin and spread pathways, although food animals have been adjudicated vehicles for passing mult-drug resistant bacteria to humans. This study analyzed 46 samples of meat purchased from retail stores in Palermo in order to obtain quinolone-resistant E. coli isolates. Strains were screened for their phylogenetic groups, ST131-associated single nucleotide polymorphisms (SNPs), and then typed by ERIC-PCR. Their set of virulence factors, namely, kpsMII, papA, sfaS, focG, iutA, papC, hlyD, and afa genes, were investigated and their fluoroquinolone-resistance determinants evaluated. The data obtained show a dramatically high prevalence of multidrug resistance patterns in the Palermo area, with 28% of the isolates having virulence factor genes typical of ExPEC strains. No B2 group or ST131 strains were detected. Moreover, 20% of our isolates showed positivity to all the plasmid-mediated quinolone resistance (PMQR) determinants, showing a potential to transfer these genes among other bacteria. Therefore, these data underline the possibility that food animals and, specifically, poultry in particular may be a significant source of resistant bacterial strains, posing a potential zoonotic risk.

https://www.ncbi.nlm.nih.gov/pubmed/30581870