Phylogroup classification and investigation the relationshipsbetween phylogroups and antibiotic resistance patterns of uropathogenicE. coli isolated from pediatric urinary tract infection

Background and Aim : One of the most challenging therapeutic fields in Pediatrics is treatingurinary tract infection (UTI) caused by the most common pathogen, uropathogenic Escherichiacoli (UPEC), with a different distribution of phylogenetic groups that acquired a variety ofantibiotic resistance phenotypes. The aims of this study were to determine the prevalence ofphylogroups and find out the relationship between resistance induced and phylogroup dominanceamong children with UTI in Hamadan, Iran.Methods : In this cross-sectional study, ۱۴۰ uropathogenic E. coli isolates from children with UTIwere investigated. Antimicrobial susceptibility testing against ۶ antibiotic classes was performedby the disk diffusion method. Isolates were subjected to phylogenetic typing using the quadruplexpolymerase chain reaction (PCR) method.Results : Antibiogram results indicate that the highest and lowest resistance were against cotrimoxazole(۶۴.۳%) and meropenem and imipenem (۰%), respectively. Phylogroup B۲ (۲۷.۹%)was predominant followed by E (۲۶.۴%), A (۱۶.۴%), Clade۱ (۱۰.۷%), B۱ (۵.۷%), C (۵.۰%), F(۴.۳%), D (۲.۹%) and unknown (۰.۷%) phylogroups. ۴۲.۱% of E. coli bacteria were multi-drugresistant (MDR) with most belonging to phylogroups E (۳۰.۵%) and B۲ (۲۷.۱%).Conclusion : Besides phylogroup B۲, phylogroup E is also dominant and a cause of muchantibiotic resistance in our study population.