Khaleque Marium, Akter Selina, Akhter Humaira, Khan Sirajul Islam, Begum Anowara
University of Dhaka, Dhaka, Bangladesh.
Jessore University of Science and Technology, Jessore, Bangladesh.
J Infect Dev Ctries. 2017 Jun 24;11(6):459-469. doi: 10.3855/jidc.8257.
Urinary tract infection is the most frequently diagnosed kidney and urologic disease.
Whether the Escherichia coli strains responsible for urinary tract infection (UPEC) carry virulence properties of diarrheagenic E. coli (DEC), 56 UPEC strains were examined for the presence of DEC and UPEC characteristics (e.g. biofilm formation, hemolysis activity, virulence genes).
Among 56 UPEC strains, 21 showed capable of biofilm formation and only 5 showed hemolysis activity on sheep blood agar. In Multiplex PCR on assessment of virulence genes related to uropathogenesis; 42% was found positive for papC gene, 27% was fim1 positive, 11% was afa positive and none was found positive for sfa. Most of the isolates were found carrying none of eight diarrhea associated genes (e.g. estA, eltB, vt1, vt2, eaeA, ea, ial and bfpA) as expected. Only seven isolates were found to harbor these genes: five genes i.e., vt2, ial, eltB, bfpA and ea were found in five different isolates and two isolates were positive for estA, among these two, one was found positive for fim1, papC along with estA, a UPEC strain containing virulent gene of ETEC strain. One isolate was found carrying fim1 and vt2 showing the property of EHEC and another isolate was found positive for fim1 and ial, the characteristic of EIEC. One isolate harboring bfpA gene characterized as EPEC and the another one was found to harbor ea gene, characterized as EAEC.
This study observed that most UPEC strains are unique to uropathogenesis, still very few may carry the diarrheagenic property.
尿路感染是最常被诊断出的肾脏和泌尿系统疾病。
为了确定引起尿路感染的大肠杆菌菌株（UPEC）是否具有致泻性大肠杆菌（DEC）的毒力特性，对56株UPEC菌株进行了DEC和UPEC特性（如生物膜形成、溶血活性、毒力基因）检测。
在56株UPEC菌株中，21株显示出具有生物膜形成能力，只有5株在绵羊血琼脂上表现出溶血活性。在评估与尿路发病机制相关的毒力基因的多重PCR中，发现42%的菌株papC基因呈阳性，27%的菌株fim1呈阳性，11%的菌株afa呈阳性，未发现sfa呈阳性的菌株。如预期的那样，大多数分离株未携带八个腹泻相关基因（如estA、eltB、vt1、vt2、eaeA、ea、ial和bfpA）中的任何一个。仅发现七株分离株携带这些基因：在五个不同的分离株中发现了五个基因，即vt2、ial、eltB、bfpA和ea，两株分离株estA呈阳性，其中一株fim1、papC与estA均呈阳性，这是一株含有ETEC菌株毒力基因的UPEC菌株。发现一株携带fim1和vt2，表现出EHEC的特性，另一株fim1和ial呈阳性，具有EIEC的特征。一株携带bfpA基因，特征为EPEC，另一株携带ea基因，特征为EAEC。
本研究观察到，大多数UPEC菌株在尿路发病机制方面具有独特性，但仍有极少数可能具有致泻特性。
