Abstract Escherichia coli is a gram-negative bacterium found in the intestines of animals and humans. Some E. coli strains can cause diarrhea, Urinary Tract Infection (UTI), and other diseases. The current study deals with molecular-phylogenetic, pathotyping groups, and antimicrobial susceptibility of E. coli isolates from diarrheic and healthy children in Babel province, Iraq. In total, stool samples were collected from 100 children under 5 years of age with diarrhea who were admitted to the Maternity Hospital and Children\\\'s Hospital in Babol, Iraq, and 40 control groups. The antimicrobial test was performed according to CLSI protocol. The PCR test was used to detect two types of genes, one for pathotypes (stx, elt, est, eaeA, aggR and ipaH) and another for phylotypes (TspE4.C2, chuA, yjaA and arpA ). Among the isolates examined, 4 distinct DEC pathotypes were identified based on their virulence genotypes: EAEC, ETEC, EIEC, and EPEC. The occurrence rates of these pathotypes in the patient group were 35%, 6%, 3%, and 1%, respectively. In fact, the majority of diarrheagenic E. coli (DEC) consisting 15% of healthy and 35% of patient groups belonged to EAEC. Most isolates belonged to phylogroup E (21%), followed by B1 (18%), A and F (11%). Antimicrobial sensitivity test results showed resistance to erythromycin, ceftazidime and trimethoprim/sulfamethoxazole in 97%, 77% and 63% of children with diarrhea, respectively. Multidrug resistance (MDR) was identified in 68% of DEC isolates. Our results underscore the significance of DEC isolates, particularly the EAEC pathotype, in causing diarrhea in children in Iraq. The notable level of antimicrobial resistance observed among DEC isolates highlights the need for implementing measures to curb the dissemination of resistant bacteria.

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