背景:泌尿致病性大肠杆菌(UPEC)分离株,有多种毒力因子促进泌尿道定植和存活。本研究旨在评估粘附素基因,生物膜形成能力,UPEC菌株的抗生素抗性概况,耐药UPEC引起UTI患者的相关危险因素。
方法:使用96孔微量滴定板评估了总共105个UPEC分离株的生物膜形成,通过PCR测定粘附素基因的存在和使用圆盘扩散方法的抗菌药物敏感性模式。调查了患者的人口统计学和临床特征,以确定耐药菌株的诱发因素。
结果:在105个UPEC分离株中,84.8%为生物膜形成阳性。产生生物膜的分离株表现出明显更高的fimH患病率,kpsMTII,csgA,afa/draBC,和pap粘附素基因与非生物膜产生菌株相比(p<0.05)。结果还显示,52.4%的分离株产生ESBL,84.8%为多重耐药(MDR)。对产生ESBL的菌株中抗生素敏感性的进一步分析显示对氨苄青霉素的耐药率最高,环丙沙星,和甲氧苄啶-磺胺甲恶唑.相反,最高的易感性,除了碳青霉烯类,观察到磷霉素,阿米卡星,头孢西丁,和呋喃妥因.我们确定高血压是产生ESBL的UPEC菌株感染的潜在危险因素。
结论:我们的结果显示,在我们地区从UTIs获得的UPEC分离株中,耐药率显著。这强调了监测抗生素的经验性使用和确定我们地理区域中特定风险因素以指导为UTI选择适当的经验性治疗的重要性。
BACKGROUND: Uropathogenic Escherichia coli (UPEC) isolates, have a wide variety of virulence factors to promote colonization and survival in the urinary tract. This study aimed to evaluate adhesin genes, biofilm formation ability, antibiotic resistance profiles of UPEC strains, and the related risk factors in patients with UTIs caused by drug-resistant UPEC.
METHODS: A total of 105 UPEC isolates were evaluated for biofilm formation using 96-well microtiter plates, the presence of adhesin genes by PCR assay and the antimicrobial susceptibility pattern using the disk diffusion method. Demographic and clinical characteristics of patients were investigated to identify predisposing factors for drug-resistant isolates.
RESULTS: Out of 105 UPEC isolates, 84.8% were positive for biofilm formation. Biofilm-producing isolates exhibited a significantly higher prevalence of fimH, kpsMTII, csgA, afa/draBC, and pap adhesin genes compared to non-biofilm-producing strains (p < 0.05). The results also revealed that 52.4% of the isolates were ESBL-producing, and 84.8% were multidrug-resistant (MDR). Further analysis of antibiotic susceptibility among ESBL-producing strains showed the highest resistance rates to ampicillin, ciprofloxacin, and trimethoprim-sulfamethoxazole. Conversely, the highest susceptibility, in addition to carbapenems, was observed for fosfomycin, amikacin, cefoxitin, and nitrofurantoin. We identified hypertension as a potential risk factor for infection with ESBL-producing UPEC strains.
CONCLUSIONS: Our results revealed a significant rate of drug resistance among UPEC isolates obtained from UTIs in our region. This underscores the importance of monitoring the empirical use of antibiotics and identifying specific risk factors in our geographical area to guide the selection of appropriate empirical treatment for UTIs.