Evaluation of Carbapenemase-Resistant Enterobacteriaceae by Disk Diffusion Test and Polymerase Chain Reaction

Carbapenemase-resistant Enterobacteriaceae is a major threat to public health. These microorganisms are resistant to all types of beta-lactam antibiotics.

This cross-sectional study was conducted on 51 Enterobacteriaceae isolates from clinical samples in Sina Hospital and Tehran Heart Center in Iran from 2016 to 2018. Antibiotic susceptibility test was performed by disk diffusion method. Carbapenem-resistant isolates were identified by the Modified Hodge Test (MHT) and Polymerase Chain Reaction (PCR) for surveying the presence of VIM, NDM, IMMP, and OXA-48 genes.

Out of 51 clinical samples, 38 isolates were positive for both MHT and PCR tests, and 5 isolates were negative in both tests. The results of both tests are similar in 84.3% of the isolates.

The MHT is an appropriate and easy method for approving carbapenemase production. Also, a laboratory can detect the carbapenemase production by identification of the KPC genes.