Comparative Evaluation of Multiplex PCR and Routine Laboratory Phenotypic Methods for Detection of Carbapenemases...

Area of Science:

• Clinical Microbiology
• Molecular Diagnostics
• Infectious Diseases

Background:

• Carbapenem-resistant pathogens are a significant cause of morbidity and mortality.
• Rapid and accurate detection is crucial for effective patient management.

Purpose of the Study:

• To evaluate Multiplex PCR for detecting carbapenemase genes in Gram-negative bacteria.
• To compare Multiplex PCR with phenotypic methods (MHT, CDT) and automated systems.

Main Methods:

• 100 carbapenem-resistant clinical isolates (E. coli, K. pneumoniae, P. aeruginosa, A. baumannii) were analyzed.
• Carbapenemase genes (blaNDM-1, blaVIM, blaIMP, blaKPC) were screened using Multiplex PCR.
• Results were compared with Modified Hodge Test (MHT) and Combined Disc Test (CDT).

Main Results:

• Multiplex PCR identified specific carbapenemase genes, including blaNDM-1 (alone or with others) and blaKPC.
• blaIMP was not detected; blaVIM was found in one isolate.
• Phenotypic methods showed varying positivity rates (MHT: 70%, CDT: 65%).

Conclusions:

• Multiplex PCR provides accurate and rapid detection of carbapenemase genes.
• Molecular methods overcome limitations of phenotypic and automated detection systems.
• This aids in timely identification of carbapenem-resistant Gram-negative bacteria.