Investigation of OXA-23 , OXA-24 , OXA-40 , OXA-51 , and OXA-58 Genes in Carbapenem-Resistant Escherichia coli and Klebsiella pneumoniae Isolates from Patients with Urinary Tract Infections

Jundishapur Journal of Microbiology

article

Elmira Pourbaghi¹  Reza Hosseini Doust¹  Mohammad Rahbar²  Marjan Rahnamaye Farzami² 

[1] Department of Microbiology, Faculty of Advanced Sciences and Technology, Tehran Medical Sciences, Islamic Azad University;Department of Microbiology, Research Center of Reference Health Laboratory, Ministry of Health and Medical Education

关键词: Escherichia coli;    Klebsiella pneumoniae;    Carbapenem;    OXA Group Genes;   

DOI  :  10.5812/jjm-119480

学科分类：微生物学和免疫学

来源: Jundishapur Journal of Microbiology

【 摘 要 】

Background: Escherichia coli and Klebsiella pneumoniae are frequently responsible for urinary tract infections (UTIs). The high rate of carbapenem resistance in Enterobacteriaceae has become a global therapeutic concern. Objectives: The study investigated OXA-23, OXA-24, OXA-40, OXA-51, and OXA-58 genes in uropathogenic E. coli and K. pneumoniae isolates. Methods: We isolated 500 uropathogenic isolates of E. coli and K. pneumoniae from patients at Milad Hospital, Tehran, Iran. Antibiotic susceptibility testing was performed using a strip-test method, and the carbapenem-nonsusceptoble isolates were confirmed with an automated antibiotic sensitivity testing system. The OXA genes were determined by multiplex PCR. Molecular typing was performed by multilocus variable-number tandem repeat (VNTR) analysis (MLVA). Results: Out of 500 isolates, 40 (8%) were detected as carbapenem-resistant, including 13 E. coli and 27 K. pneumoniae. All carbapenem-resistant isolates were ESBL-producing and resistant to ceftriaxone, ciprofloxacin, meropenem, ceftazidime, and amoxicillin-clavulanate. Moreover, 46.1% and 26% of carbapenem-insensitive E. coli and K. pneumoniae isolates carried a beta-lactamase-producing gene associated with the OXA-23-like group. Finally, E. coli and K. pneumoniae isolates were divided into two and three MLVA patterns, respectively. Conclusions: This is the first report of OXA-51, 58, and 24 carbapenemases in clinical isolates of E. coli and K. pneumoniae from UTI patients in Iran. Significant differences were seen in OXA-51, 58, and 24 genes between carbapenem-insensitive and carbapenem-sensitive E. coli and K. pneumoniae isolates. Molecular typing suggested the vertical transmission of resistance genes.

【 授权许可】

CC BY-NC