Background: Escherichia coli strains mainly fall into four phylogenetic groups (A, B1, B2, and D) and that virulent extra‑intestinal strains mainly belong to groups B2 and D. Aim: The aim was to determine the association between phylogenetic groups of E. coli causing extraintestinal infections (ExPEC) regarding the site of infection, expression of virulence factors, antimicrobial resistance patterns, and clinical outcome. This descriptive study was carried out in a multi‑specialty Tertiary Care Hospital.

Materials and Methods: A total of 300 E. coli causing ExPEC were studied. Triplex polymerase chain reaction was used to classify the phylogenetic groups; hemolysin production was assessed on sheep blood agar and biofilm production in a microtiter plate assay. Production of extended spectrum of beta‑lactamase (ESBLs) was detected by combination disk method; AmpC was detected by AmpC disk…