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

This study aimed at the characterization of carbapenem-resistant isolates focusing on typing of the genes. Additionally, the correlation between the resistance pattern and biofilm formation capacity of the carbapenem-resistant 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 (, , , , and ) were detected by PCR. Isolates harboring 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 gene was tested by chemical transformation. The biofilm formation capacity and the prevalence of the genes encoding the fimbrial adhesins and ) 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 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 and were prevalent among the isolates. The prevalence of carbapenemases encoding genes, especially genes in Egyptian healthcare settings, is worrisome and necessitates further strict dissemination control measures.