Harwalkar Anandkumar, Gupta Soham, Rao Achyut, Srinivasa Hiresave
Department of Microbiology, Navodaya Medical College, Raichur, Karnataka, India
Department of Microbiology, St. John's Medical College, Bangalore, Karnataka, India.
Trans R Soc Trop Med Hyg. 2015 Dec;109(12):769-74. doi: 10.1093/trstmh/trv086. Epub 2015 Nov 12.
We aimed to determine the virulence factor profile and phylogenetic grouping of uropathogenic Escherichia coli (UPEC) causing urinary tract infection (UTI) in patients with and without diabetes mellitus (DM).
A total of 280 UPEC were collected from the urine samples of patients with DM (n=126) and patients suffering from non-DM UTIs (n=154). All isolates were subjected to phenotypic and genotypic virulence factor profile and phylogenetic grouping.
There was no significant difference in phenotypic virulence factors of UPEC causing UTI from patients with and without DM; alpha-haemolysin (DM=52, 41.2%; non-DM=69, 44.8%), mannose resistant haemagglutination (DM=6, 36.2%; non-DM=64, 41.5%), biofilm production (DM=33.3%; non-DM=25.9%), serum resistance (DM=27, 21.4%; non-DM=46, 29.8%), cell surface hydrophobicity (DM=22, 17.1%; non-DM=18, 11.6%) and mannose sensitive hemagglutnation (DM=18, 14.2%; non-DM=29, 18.8%). Among the genotypic virulence markers, papC gene was most prevalent in both patients with DM (n=65, 51.6%) and without DM (n=88, 57.1%), followed by hlyD gene (DM=36, 28.6%; non-DM=52, 33.8%). Only cnf-1 gene was observed to be significantly associated (p<0.05) with the non-DM status (n=35, 22.7%) than DM (n=15, 11.9%). Irrespective of the diabetic status, majority of the UPEC isolates (approximately 50%) belonged to phylogenetic group B2 predominantly harboring the virulence genes papC, hlyD and cnf-1.
This study demonstrates that there may not be a differential selection of virulence properties of UPEC causing UTI in patients with DM and in the general population.
我们旨在确定导致糖尿病患者和非糖尿病患者尿路感染（UTI）的尿路致病性大肠杆菌（UPEC）的毒力因子谱和系统发育分组。
从糖尿病患者（n = 126）和非糖尿病尿路感染患者（n = 154）的尿液样本中总共收集了280株UPEC。所有分离株均进行表型和基因型毒力因子谱分析及系统发育分组。
导致糖尿病患者和非糖尿病患者UTI的UPEC的表型毒力因子无显著差异；α-溶血素（糖尿病患者=52株，41.2%；非糖尿病患者=69株，44.8%）、甘露糖抗性血凝（糖尿病患者=6株，36.2%；非糖尿病患者=64株，41.5%）、生物膜形成（糖尿病患者=33.3%；非糖尿病患者=25.9%）、血清抗性（糖尿病患者=27株，21.4%；非糖尿病患者=46株，29.8%）、细胞表面疏水性（糖尿病患者=22株，17.1%；非糖尿病患者=18株，11.6%）和甘露糖敏感血凝（糖尿病患者=18株，14.2%；非糖尿病患者=29株，18.8%）。在基因型毒力标志物中，papC基因在糖尿病患者（n = 65株，51.6%）和非糖尿病患者（n = 88株，57.1%）中最为普遍，其次是hlyD基因（糖尿病患者=36株，28.6%；非糖尿病患者=52株，33.8%）。仅观察到cnf-1基因与非糖尿病状态（n = 35株，22.7%）显著相关（p<0.05），而与糖尿病状态（n = 15株，11.9%）无关。无论糖尿病状态如何，大多数UPEC分离株（约50%）属于系统发育组B2，主要携带毒力基因papC、hlyD和cnf-1。
本研究表明，导致糖尿病患者UTI的UPEC与普通人群中UTI的UPEC在毒力特性上可能没有差异选择。
