Halimi Shahnaz, Rezaei Akram, Mohebi Shirin, Hashemi Farhad Bonakdar
Department of Medical Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
Iran J Microbiol. 2025 Feb;17(1):32-40. doi: 10.18502/ijm.v17i1.17799.
Enteropathogenic (EPEC) strains are emerging pathogens around the world, particularly among pediatric patients in developing countries, such as Iran. This study aims to examine and compare the characteristics of EPEC isolates from patients, who suffer from diarrhea versus isolates from patients without diarrhea.
A total of 734 stool specimens [440 diarrheal (D), and 294 non-diarrheal (ND)] were examined. Thirty-six EPEC isolates (26 D, and 10 ND) were recovered by culture on MacConkey agar, followed by biochemical tests. Using PCR assay, ; and gene profiles of EPEC isolates were confirmed. The antimicrobial resistance was assessed by disk diffusion assay. Biofilm formation was assessed using a standard semi-quantitative microtiter plate assay. Virulence-associated genes, and were detected.
comprised 14% of all isolates were EPEC isolates that showed the highest sensitivity to imipenem (IPM) (100%) and gentamicin (GEN) (89%). However, susceptibility to ciprofloxacin and cotrimoxazole or trimethoprim\sulfamethoxazole (SXT) was only 28% and 39%, respectively. About 61% of isolates produced Moderate Biofilm (MB), and the frequency of Weak Biofilm (WB) formers (27%) was higher among D and ND isolates, which carried virulence genes more frequently than D isolates.
Preventive measures by public health authorities can thwart the imminent crisis of widespread zoonotic contamination of the food chain in Iran. Our results may help clinicians make optimal therapeutic choices during the treatment of patients with severe EPEC infections, and assist epidemiologists devise policies for effective control of outbreaks.
肠致病性大肠杆菌（EPEC）菌株在全球范围内都是新兴病原体，在发展中国家的儿科患者中尤为常见，比如伊朗。本研究旨在检查并比较腹泻患者与无腹泻患者的EPEC分离株的特征。
共检查了734份粪便标本[440份腹泻标本（D）和294份非腹泻标本（ND）]。通过在麦康凯琼脂上培养，随后进行生化试验，分离出36株EPEC（26株D和10株ND）。使用聚合酶链反应（PCR）检测确认EPEC分离株的 、 和 基因谱。通过纸片扩散法评估抗菌药物敏感性。使用标准半定量微量滴定板法评估生物膜形成情况。检测毒力相关基因 和 。
所有分离株中14%为EPEC分离株，这些分离株对亚胺培南（IPM）（100%）和庆大霉素（GEN）（89%）表现出最高敏感性。然而，对环丙沙星和复方新诺明或甲氧苄啶/磺胺甲恶唑（SXT）的敏感性分别仅为28%和39%。约61%的分离株产生中度生物膜（MB），弱生物膜（WB）形成菌的频率在D和ND分离株中更高（27%），且携带毒力基因的频率高于D分离株。
公共卫生当局采取的预防措施可以避免伊朗即将出现的食物链广泛人畜共患污染危机。我们的结果可能有助于临床医生在治疗严重EPEC感染患者时做出最佳治疗选择，并协助流行病学家制定有效控制疫情爆发的政策。
