%0 Journal Article
%T Vaginal Colonization by papG Allele II+ Escherichia coli Isolates from Pregnant and Nonpregnant Women as Predisposing Factor to Pyelonephritis
%A Sareaa Maseer Gatya Al-Mayahie
%J Infectious Diseases in Obstetrics and Gynecology
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/860402
%X Vaginal (61) and fecal (61) Escherichia coli isolates from pregnant and nonpregnant women (18¨C45 years old) were surveyed for papG alleles by PCR technique. papG allele II was the most prevalent among both vaginal (32.7%) and fecal (3.2%) isolates, whereas other alleles were found only among vaginal isolates (1.6% for alleles I and III and 3.2% for alleles II + III). papG+ pregnant women's isolates did not differ significantly from those of nonpregnant in possession of papG allele II (90% versus 73.3%), whereas both (32.7%) differed significantly ( ) in comparison with fecal isolates (3.2%). The vast majority of papG allele II+ vaginal isolates were clustered in group B2 (81.8%) and much less in group D (18.1%). Also, most of them were positive for fimH (100%), papC (100%), iucC (90.9%), and hly (72.7%), and about half of them were positive for sfa/foc (45.4%). In addition, the mean of VFs' gene possession was 3.5 (range from 2 to 5). It can be concluded that vaginal colonization by papG allele II+ E. coli is possibly one of the predisposing factors of both pregnant and nonpregnant women to pyelonephritis, but its potential may be modified by other factors especially host factors. 1. Introduction Bacterial adherence is an essential step in all infections which involves surface interactions between specific receptors on the mammalian cell membrane and ligands on the bacterial surface. Tissue specificity of infection is determined significantly by the presence or absence of specific receptors on mammalian cells [1]. The ability of uropathogenic Escherichia coli (UPEC) to adhere to host uroepithelia is an important stage in the successful colonization of the urinary tract and pathogenesis of urinary tract infection (UTI). The principal adherence organelle of UPEC is P fimbriae, which mediates Gal(¦Á1-4)Gal-specific binding via the adhesin molecule PapG [2]. The three molecular variants (I to III) of the adhesin are coded by the adhesin gene papG of which there are three known alleles [3]. These variants exhibit different receptor binding specificities [4]. Naturally, papG alleles occurin four combinations, that is, class ¦© plus III, class III only, class II plus III, and class II only [2, 5]. According to the receptor specificity of the PapG adhesin, p-fimbriated uropathogenic E. coli is clinically divided into two subtypes: papG allele II+ strains associated with pyelonephritis and bacteremia, and papG allele III+ strains associated with cystitis but have been found in pyelonephritis and bacteremia [2, 5¨C7]. The most common extraintestinal E. coli
%U http://www.hindawi.com/journals/idog/2013/860402/