Carbapenem-resistant Klebsiella pneumoniae isolates from Egypt containing blaNDM-1 on IncR plasmids and its association with rmtF

Abstract

Objectives: The aim of this study was to characterize carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates recovered from clinical specimens at a tertiary care hospital in Egypt over a period of 15 months.

Methods: Eight CRKP isolates were included in this study. The minimum inhibitory concentrations of different antibiotics were determined by broth microdilution and Etest methods. Multilocus sequence typing was performed. Antibiotic resistance genes were assessed by PCR and DNA sequencing. Plasmid analysis was done by S1 nuclease digestion of whole genomic DNA followed by pulsed-field gel electrophoresis (S1-PFGE).

Result: Eight carbapenem-resistant NDM-1-producing K. pneumoniae isolates of three different sequence types (ST) were identified (ST147, ST11, and ST17), in which blaNDM-1 was carried by either IncR or untypeable plasmids. Seven out of the eight isolates also contained the rmtF methylase gene.

Conclusion: This study describes the occurrence of IncR plasmids carrying blaNDM-1 and rmtF in Egypt, raising concerns regarding this type of replicon and its role in the transmission of these resistance determinants.

Keywords: Carbapenemases; Enterobacteriaceae; IncR plasmids; Methyl transferases; β-Lactamases.