Ruchi Agrawal, Ramesh P Agrawal, Taruna Singh
mCIM in combination with eCIM demonstrated superior reliability compared to MHT for phenotypic detection of carbapenemase-producing Klebsiella. These methods can be adopted as routine diagnostic tools in clinical microbiology laboratories.
BACKGROUND: The rapid emergence of carbapenem-resistant Klebsiella species poses a serious threat to antimicrobial therapy and infection control worldwide. Reliable phenotypic detection of carbapenemase production is essential, particularly in resource-limited laboratory settings.
OBJECTIVES: To compare the diagnostic performance of the modified Hodge test (MHT), modified carbapenem inactivation method (mCIM), and Ethylenediaminetetraacetic acid (EDTA)-modified carbapenem inactivation method (eCIM) for identifying carbapenemase-producing Klebsiella isolates.
MATERIALS AND METHODS: This cross-sectional study included 80 non-duplicate Klebsiella isolates obtained from various clinical samples over one year. Isolates resistant to imipenem and/or meropenem were screened for carbapenemase production and confirmed using MHT, mCIM, and eCIM as per clinical and laboratory standards institute (CLSI) guidelines. Statistical analysis was performed using SPSS software version 29.0 (IBM Corp., Armonk, NY, USA).
RESULTS: Out of 80 isolates, 52 (65.0%) were carbapenemase producers on screening. Positivity rates for MHT, mCIM, and eCIM among screened isolates were 73.1%, 92.3%, and 92.3%, respectively. A statistically significant agreement was observed between mCIM and eCIM (P < 0.001).
CONCLUSION: mCIM in combination with eCIM demonstrated superior reliability compared to MHT for phenotypic detection of carbapenemase-producing Klebsiella. These methods can be adopted as routine diagnostic tools in clinical microbiology laboratories.