Genotypic analysis of E. coli strains isolated from patients with cystitis and pyelonephritis

Urinary tract infection is the most common health problem affecting millions of people each year, mainly caused by a large genetically heterogeneous group of Escherichia coli called uropathogenic E. coli. This study investigates the genotypic analysis of E. coli strains isolated from patients with cystitis and pyelonephritis. During 2008-2009, 90 E. coli strains were analyzed, consisting of 48 isolates causing pyelonephritis in children and 42 isolates causing cystitis. Having identified the strains by standard methods, they were subtyped by pulsed field gel electrophoresis [PFGE] and their corresponding patterns were compared using dendrogram. Sixty five PFGE profiles were obtained from the genome of E. coli strains by this genotyping method. Thirty six and thirty three patterns were obtained for pyelonephritis and cystitis, respectively. Most strains exhibited twelve and thirteen bands and the patterns with eight or nineteen bands had the lowest rate. Genome sizes of the strains were between 1610-4170 kbp. With due attention to these results, genetic patterns showed that the strains had different clonalities and it could be suggested in some cases that the strains causing pyelonephritis or cystitis have common patterns and different diseases could be explained by different gene factors