Detection of IS903, IS26 and ISEcp1 elements in CTX-M-producing klebsiella pneumoniae and escherichia coli isolates from patients with leukemia in Iran

Abstract

Background: The ability of extended spectrum beta-lactamases (ESBLs) production is one of the main mechanisms for the emergence of antibiotic resistance in Escherichia coli and Klebsiella pneumoniae. Objectives: The aim of this study was to evaluate the occurrence of IS903, IS26, and ISEcp1 insertion elements among the CTX-M-producing K. pneumoniae and E. coli isolates from patients with leukemia in Tehran. Methods: Eighty E. coli and K. pneumoniae isolates were recovered from patients admitted to hospitals of Tehran. Antibiotic susceptibility tests were performed by Kirby-Bauer disc diffusion and broth microdilution methods. Detection of ESBL producers was evaluated by phenotypic confirmatory test. The presence of IS903, IS26, and ISEcp1 insertion elements in CTX-M-positive E. coli and K. pneumoniae isolates was investigated by PCR-sequencing methods. Results: The rate of resistance of 80 E. coli and K. pneumoniae isolates against the nine antibiotics was as follows: 100% to ampicillin, 15% to amikacin, 51% to ciprofloxacin, 30% to gentamicin, 58% to ceftriaxone, 10% to imipenem, 63% to cefotaxime, 51% to levofloxacin, and 55% to ceftazidime. Using phenotypic confirmatory test revealed that 51 (63.75%) isolates were ESBL producers. The prevalence of CTX-M-1, CTX-M-2, CTX-M-9, CTX-M-8, and CTX-M-25 genes was 87.5%, 13.75%, 23.75%, 10%, and 0%, respectively. IS903, IS26, and ISEcp1 elements were detected in 93.75%, 71.25%, and 100% of the isolates, respectively. Conclusions: This study indicates that the high prevalence of antibiotic resistance, IS and CTX-M-producing E. coli, and K. pneumoniae isolates could be a major concern and highlights the need for infection control measures.