Phenotypic and Genotypic Features of Klebsiella pneumoniae Harboring Carbapenemases in Egypt: OXA-48-Like Carbapenemases as an Investigated Model.

Suzan Mohammed Ragheb,Amani Ali El-Kholy,Mahmoud Mohamed Tawfick,Abeer Khairy Abdulall

doi:10.3390/antibiotics9120852

Abstract

This study aimed at the characterization of carbapenem-resistant Klebsiella pneumoniae isolates focusing on typing of the blaOXA-48-like genes. Additionally, the correlation between the resistance pattern and biofilm formation capacity of the carbapenem-resistant K. pneumoniae isolates was studied. The collected isolates were assessed for their antimicrobial resistance and carbapenemases production by a modified Hodge test and inhibitor-based tests. The carbapenemases encoding genes (blaKPC, blaNDM, blaVIM, blaIMP, and blaOXA-48-like) were detected by PCR. Isolates harboring blaOXA-48-like genes were genotyped by Enterobacterial Repetitive Intergenic Consensus-Polymerase Chain Reaction (ERIC-PCR) and plasmid profile analysis. The discriminatory power of the three typing methods (antibiogram, ERIC-PCR, and plasmid profile analysis) was compared by calculation of Simpson’s Diversity Index (SDI). The transferability of blaOXA-48 gene was tested by chemical transformation. The biofilm formation capacity and the prevalence of the genes encoding the fimbrial adhesins (fimH-1 and mrkD) were investigated. The isolates showed remarkable resistance to β-lactams and non-β-lactams antimicrobials. The coexistence of the investigated carbapenemases encoding genes was prevalent except for only 15 isolates. The plasmid profile analysis had the highest discriminatory power (SDI = 0.98) in comparison with ERIC-PCR (SDI = 0.89) and antibiogram (SDI = 0.78). The transferability of blaOXA-48 gene was unsuccessful. All isolates were biofilm formers with the absence of a significant correlation between the biofilm formation capacity and resistance profile. The genes fimH-1 and mrkD were prevalent among the isolates. The prevalence of carbapenemases encoding genes, especially blaOXA-48-like genes in Egyptian healthcare settings, is worrisome and necessitates further strict dissemination control measures.

Highlights

Antimicrobial resistance is among the serious problems that contribute to high morbidity and mortality rates, in immunocompromised patients [1]
There is an expansion in the number of emerged carbapenemases, five important members that belong to three Ambler classes are the most studied, namely, Klebsiella pneumoniae carbapenemases, New Delhi metallo-β-lactamases, Verona integron-encoded metallo-β-lactamases, Active on imipenem metallo-β-lactamases, and Oxacillinase-48-like carbapenemases [7,8]
We studied the prevalence of the ”big five” carbapenemases encoding genes, among carbapenem-resistant K. pneumoniae isolated from a tertiary hospital in Egypt

Summary

Introduction

Antimicrobial resistance is among the serious problems that contribute to high morbidity and mortality rates, in immunocompromised patients [1]. There is an expansion in the number of emerged carbapenemases, five important members that belong to three Ambler classes are the most studied, namely, Klebsiella pneumoniae carbapenemases (blaKPC ), New Delhi metallo-β-lactamases (blaNDM ), Verona integron-encoded metallo-β-lactamases (blaVIM ), Active on imipenem metallo-β-lactamases (blaIMP ), and Oxacillinase-48-like carbapenemases (blaOXA-48-like ) [7,8]. These carbapenemases have several variants according to the National Center for Biotechnology Information (NCBI) Antimicrobial Resistance

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