Molecular analysis of uropathogenic strains of Escherichia coli and the clinical course of urinary tract infection in children

UNLABELLED: The most frequent etiological factor of urinary tract infections are virulent Escherichia coli strains. Identification of uropathogenic Escherichia coli strains is possible using biomolecular techniques. THE PURPOSE OF THIS STUDY was to determine the prevalence of Escherichia coli strains encoding papG adhesins and adhesins of Dr family in children with urinary tract infections and to establish the relationship between the bacterial genotype and clinical course of a sickness. MATERIAL AND METHODS: In 163 children with urinary tract infection caused by Escherichia coli strains, after taking history and physical examination, inflammatory parameters were determined. In all patients abdominal ultrasonography and in chosen patients -- miction cystourethrography and urodynamic examinations were performed. In order to identify Escherichia coli strains possessing pap gene cluster class I, II and III (encoding P fimbriae) and genes encoding Dr family of adhesins, the Polymerase Chain Reaction was used. RESULTS AND CONCLUSIONS: From all isolated Escherichia coli strains, pap gene cluster was identified in 41.1% and dra gene cluster in 42.3%. Escherichia coli strains encoding papG gene class II frequently caused upper urinary tract injections, while strains encoding papG gene class III and genes encoding adhesins of Dr family were mostly responsible for lower urinary tract infections and their recurrences. Occurrence of virulent Escherichia coli strains was not more common in children with pyelonephritis and with disorders of urinary tract in comparison with the group of children without urinary tract anomalies. Determination of bacterial virulence factors causing urinary tract infections in children may be helpful in the prognosis of the course of the disease.