Carbapenem Resistance in Gram-Negative Bacteria: A Hospital-Based Study in Egypt

Area of Science:

• Clinical Microbiology
• Infectious Diseases
• Molecular Epidemiology

Background:

• Carbapenem resistance in Enterobacteriaceae (CRE) is a global health priority due to high mortality.
• The World Health Organization (WHO) has identified CRE as priority pathogens.
• Understanding resistance mechanisms, including carbapenemase genes and plasmids, is crucial for effective control.

Purpose of the Study:

• To determine the prevalence of carbapenemase-encoding genes in Gram-negative hospital isolates in Egypt.
• To identify major plasmid incompatibility groups associated with carbapenem resistance.
• To investigate the association between carbapenemase genes and plasmid replicons.

Main Methods:

• A cross-sectional study conducted at Mansoura University Hospitals over 12 months (January-December 2019).
• Isolates were tested for carbapenem resistance.
• Conventional polymerase chain reaction (PCR) screened for carbapenemase genes (blaKPC, blaNDM, blaVIM, blaOXA-48).
• PCR-based plasmid replicon typing (PBRT) identified plasmid incompatibility groups.

Main Results:

• 20% (30/150) of isolates exhibited carbapenem resistance.
• Klebsiella pneumoniae was the most resistant species.
• blaNDM was the predominant carbapenemase gene.
• F replicon (FIA, FIB, FII) and A/C were the most prevalent plasmid replicons.
• A significant association was found between carbapenemase genes (blaNDM) and plasmid replicons (IncA/C, IncX).

Conclusions:

• An alarming increase in plasmid-mediated carbapenem-resistant bacteria was observed in the study area.
• The co-occurrence of resistance genes and plasmids necessitates targeted antibiotic surveillance and alternative therapies.
• Recommendations include large-scale studies, broader gene screening, comparative plasmid detection methods, and a national action plan to control antibiotic misuse.