Department of Microbiology, Virology and Microbial Toxins, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
Department of Genetic, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
J Infect Dev Ctries. 2024 May 30;18(5):761-769. doi: 10.3855/jidc.18566.
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.
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.
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.
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.
尿路致病性大肠杆菌（UPEC）分离株具有多种毒力因子，可促进其在泌尿道的定植和存活。本研究旨在评估耐药 UPEC 引起的尿路感染患者的黏附基因、生物膜形成能力、抗生素耐药谱以及相关的危险因素。
使用 96 孔微量滴定板评估 105 株 UPEC 分离株的生物膜形成能力，通过 PCR 检测黏附基因的存在，采用纸片扩散法检测抗生素药敏模式。调查患者的人口统计学和临床特征，以确定耐药分离株的易患因素。
在 105 株 UPEC 分离株中，84.8%呈生物膜阳性。与非生物膜产生菌株相比，生物膜产生菌株 fimH、kpsMTII、csgA、afa/draBC 和 pap 黏附基因的阳性率显著更高（p<0.05）。结果还显示，52.4%的分离株为 ESBL 产生菌，84.8%为多重耐药（MDR）。对 ESBL 产生菌的抗生素药敏分析进一步显示，对氨苄西林、环丙沙星和复方磺胺甲噁唑的耐药率最高。相反，除碳青霉烯类外，对磷霉素、阿米卡星、头孢西丁和呋喃妥因的敏感性最高。我们发现高血压是感染 ESBL 产生 UPEC 菌株的一个潜在危险因素。
我们的研究结果显示，从本地区尿路感染患者中分离出的 UPEC 分离株存在显著的耐药率。这凸显了监测经验性使用抗生素的重要性，并确定我们地理区域的特定危险因素，以指导针对尿路感染的经验性治疗选择。
