由于抗生素耐药性,尿路感染每年都变得难以治疗。泌尿致病性大肠杆菌(UPEC)分离株对多药耐药性和生物膜形成的联合表达构成威胁。ST131克隆是一种高风险的大流行克隆,因为它与抗菌素耐药性密切相关,近年来经常有报道。本研究旨在定义风险因素,临床结果,和与ST131/O25bUPEC相关的细菌遗传学。在这项研究中,我们通过自动化系统测定了61株临床大肠杆菌的抗生素敏感性和种属水平鉴定.通过双盘协同试验评估广谱β-内酰胺酶的检测。通过分光光度法定量生物膜形成。毒力基因(iutA,sfacnf-1,iroN,afa,爸爸,fimA),抗生素抗性基因(blaCTX-M,blaTEM,blaSHV,blaOXA,qnrA,qnrB,qnrS,蚂蚁(2')-Ia,ant(3)-Ia,aac(3)-IIa,通过PCR研究mcr-1,mcr-2,mcr-3,mcr-4)。鉴定了以下β-内酰胺酶基因,blaTEM(n=53,86.8%),blaCTX-M(n=59,96.7%),blaSHV(n=47,77.0%),和blaOXA-1(n=27,44.2%)。我们的数据揭示了93.4%的(57/61)大肠杆菌分离物是生物膜生产者。研究了O25pabBspe和trpA2是否存在ST131/O25b克隆。在多重耐药分离株中,在29个分离物中检测到O25pabBspe和trpA2共存(47.5%)。在四个强生物膜生产者分离物中检测到fimH30和H30Rx亚克隆。这些结果表明临床大肠杆菌菌株可能成为毒力和抗生素抗性基因的储库。该研究证明了大肠杆菌ST131和非ST131分离株之间生物膜形成的显著差异。此外,86.21%(n=25)的ST131分离株产生了强至中等的生物膜,而只有43.75%(n=14)的非ST131分离株显示出形成强生物膜的能力。大多数ST131菌株中iutA和fimA基因的存在在生物膜形成中显示出重要作用。这些发现表明iutA和fimA基因抑制剂在治疗由产生生物膜的耐药ST131菌株引起的感染中的应用。
Urinary tract infections are becoming difficult to treat every year due to antibiotic resistance. Uropathogenic Escherichia coli (UPEC) isolates pose a threat with a combined expression of multidrug-resistance and biofilm formation.
ST131 clone is a high-risk pandemic clone due to its strong association with antimicrobial resistance, which has been reported frequently in recent years. This study aims to define risk factors, clinical outcomes, and bacterial genetics associated with
ST131/O25b UPEC. In this study, antibiotic susceptibility and species-level identification of 61 clinical E. coli strains were determined by automated systems. Detection of extended-spectrum beta-lactamases was assessed by double-disk synergy test. Biofilm formation was quantified by spectrophotometric method. Virulence genes (iutA, sfa cnf-1, iroN, afa, papA, fimA), antibiotic resistance genes (blaCTX-M, blaTEM, blaSHV, blaOXA, qnrA, qnrB, qnrS, ant(2\')-Ia, ant(3)-Ia, aac(3)-IIa, mcr-1, mcr-2, mcr-3, mcr-4) were investigated by PCR. The following beta-lactamase genes were identified, blaTEM (n = 53, 86.8%), blaCTX-M (n = 59, 96.7%), blaSHV (n = 47, 77.0%), and blaOXA-1 (n = 27, 44.2%). Our data revealed that 93.4% of (57/61) E. coli isolates were biofilm-producers. O25pabBspe and trpA2 were investigated for the presence of
ST131/O25b clone. Among multidrug resistant isolates, co-existence of O25pabBspe and trpA2 was detected in 29 isolates (47.5%). The fimH30 and H30Rx subclones were detected in four isolates that are strong biofilm-producers. These results suggest that clinical E. coli strains may become reservoirs of virulence and antibiotic resistance genes. This study demonstrates a significant difference in biofilm formation between E. coli
ST131 and non-
ST131 isolates. Moreover, 86.21% (n = 25) of ST131 isolates produced strong to moderate biofilms, while only 43.75% (n = 14) of non-
ST131 isolates showed the ability to form strong biofilms. Presence of iutA and fimA genes in the majority of ST131 strains showed an important role in biofilm formation. These findings suggest application of iutA and fimA gene suppressors in treatment of infections caused by biofilm-producing drug-resistant ST131 strains.