Virulence-associated genes and drug susceptibility patterns of uropathogenic Escherichia coli isolated from patients with urinary tract infection Ahmad Farajzadah Sheikh,1,2 Hamed Goodarzi,1–3 Mohammad Jaafar Yadyad,1 Sajad Aslani,4 Mansoor Amin,1,2 Nabi Jomehzadeh,5 Reza Ranjbar,3 Mina Moradzadeh,1 Samireh Azarpira,1 Mohamad Reza Akhond,6 Mohamad Hashemzadeh1,21Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; 2Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; 3Molecular Biology Research Center, Baqiyatallah University of Medical Science, Tehran, Iran; 4Student Research Committee, Kerman University of Medical Sciences, Kerman, Iran; 5Abadan Faculty of Medical Sciences, Abadan, Iran; 6Department of Statistics, Mathematical Science and Computer Faculty, Shahid Chamran University, Ahvaz, IranBackground: Different Escherichia coli phylogenetic groups, such as A, B1, B2, and D, have four functional groups – adhesins, microcins, toxins, and capsules – which can cause urinary tract infections (UTIs). A phylogenetic group with a high virulence content becomes a worldwide health concern. Resistance to antimicrobial agents increasingly complicates the management of E. coli extraintestinal infections, as a major source of illness, death, and increased health care costs. The aim of this study was to determine the virulence content and the antimicrobial susceptibility pattern of different uropathogenic E. coli (UPEC) phylogenetic groups in Ahvaz, Iran.Methods: Phylogenetic groups, virulence-associated genes (VAGs), and antimicrobial susceptibility tests were detected by molecular and phenotypic methods in a total of 232 clinically well-characterized E. coli strains, isolated from two collections of patients with hospital-acquired (HA) and community-acquired (CA) UTIs.Results: Our results revealed that among 232 UPEC strains, the most frequent phylogenetic group was phylogroup D (58%) with the greatest content in virulence factors, including kpsM (23%), neuA (76.3%, capsule), cnf (29.6%, toxin), and Pap (54.8%, adhesin). Phylogroups D and, to a lesser extent, B2 were the most drug-resistant phylogroups. In addition, phylogroup D was responsible for the majority of HA (64.7%) and CA (48.4%) infections.Conclusion: Among UPEC strains causing UTIs, different phylogroups, through different VAGs, could cause severe infection. Knowledge about the distribution of the four functional groups and VAGs belonging to these phylogroups would significantly help to confine and prevent the development of lethal infection caused by these strains.Keywords: uropathogenic Escherichia coli, drug resistance, virulence factors, Iran