ANTIBIOTIC RESISTANCE, VIRULENCE AND GENETIC DIVERSITY OF KLEBSIELLA PNEUMONIAE IN COMMUNITY- AND HOSPITAL-ACQUIRED URINARY TRACT INFECTIONS IN IRAN FATEMEH EGHBALPOOR 1 ,MEHRI HABIBI 1 ,OMID AZIZI 2 , MOHAMMAD REZA ASADI KARAM 1 * and SAEID BOUZARI 1 1 Department of Molecular Biology, Pasteur Institute of Iran, Tehran, Iran 2 Health Sciences Research Center, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran (Received: 20 November 2018; accepted: 14 January 2019) Klebsiella pneumoniae is among the most important causes of urinary tract infection (UTI). The aim of this study was to investigate the prevalence and correlation of antibiotic resistance with virulence characteristics and genetic diversity in K. pneumoniae isolated from UTIs in Iran. Phenotypic tests and antibiotic suscepti- bility were carried out on the isolates. Detection of the virulence and extended- spectrum β-lactamase (ESBL) genes was performed by polymerase chain reaction. Pulsed-field gel electrophoresis (PFGE) was used for exploring the genomic related- ness. Hemolysin, biofilm, and hypermucoviscosity formation were observed in 87.1%, 86.4%, and 12.1% of isolates, respectively. The antibiotic resistance rate of K. pneumoniae isolates ranged from 12.1% for meropenem to 100% for amoxicillin. The prevalence of virulence genes ranged from 1.4% for cnf-1 to 100% for mrkD, fimH, kpn, and entB genes. In this study, 91.7%, 33.3%, and 4.2% of phenotypically ESBL-producers were positive for bla CTX-M , bla TEM , and bla SHV genes, respectively. An association was observed between the presence of traT, fyuA, or cnf-1 genes with antibiotic resistance. Two clone types were obtained by PFGE that indicate different K. pneumoniae clones in community- and hospital-acquired UTIs. The findings of this study are valuable in development of treatment strategies against UTIs in Iran. Keywords: urinary tract infections, Klebsiella pneumoniae, antibiotic resistance, ESBL, virulence factors, PFGE *Corresponding author; E-mail: m_asadi12@yahoo.com Acta Microbiologica et Immunologica Hungarica 66 (3), pp. 349–366 (2019) DOI: 10.1556/030.66.2019.006 First published online February 26, 2019 1217-8950/$20.00 © 2019 Akadémiai Kiad´ o, Budapest