Selected virulence factors of uropathogenic Escherichia coli strains and clinical course of urinary tract infections in children

摘要

Urinary tract infections (UTI) are one of the most common diseases of bacterial etiology occurring in children. Most frequently the etiologic factor is Escherichia coli (E.coli ). Literature data emphasize a significant role of uropathogenic E.coli virulence factors (P fimbria, type 1, dr, hemolysin, aerobactin) in the clinical course of UTI. Current epidemiological studies more and more often use genotyping methods to determine the aforementioned factors. The paper contains a review of literature concerning the correlation between the presence of selected virulence factors of uropathogenic E.colistrains and the clinical course of UTI. Additionally, preliminary results of own studies assessing the prevalence of pap and dra genotypes in E.coli cultured from urine of children with diagnosed UTI are presented. Polymerase chain reaction (PCR) method was used in the study. Among the total of 163 uropathogenic E.coli isolates, 70 (42.2%) P-fimbriated strains with class II and III adhesin were identified. The class II gene was present in 36 (22.1%), and the class III one in 34 (20.1%) E.coli isolates. No strains possessing the PapG class I adhesin-encoding gene were identified, whereas strains encoding drfamily adhesins were found in 69 (42.3%) samples.