English

Abstract

BACKGROUND In an infection caused by multidrug-resistant Enterobacteriaceae, carbapenems is one the last antibiotics used, but the carbapenemase producing Enterobacteriaceae pose a clinical challenge. A relatively new test which was described few years back known as modified carbapenem inactivation method (mCIM) is used to detect the presence of carbapenemase activity in Gramnegative bacilli. Various studies show this test be to be very sensitive and specific. We aim to study mCIM positivity on samples which are positive by Kirby-Bauer disk diffusion antibiotic sensitivity test method used for detection of carbapenem resistant Enterobacteriaceae (CRE) from clinical specimens. METHODS The study is a cross sectional descriptive study conducted in a tertiary care hospital. Samples received from February 2019 to September 2019 were included in the study. During this period 150 samples were collected which were resistant to meropenem by Kirby-Bauer disk diffusion method. These CREs isolates were further subjected to mCIM and the result was analysed. RESULTS Out of the total 150 CRE isolates which were 100 % resistant to meropenem by the conventional disc diffusion method it is found that mCIM was positive for 148 (98.66 %) isolates and negative for only 02 (1.33 %). Two most common CRE were Klebsiella pneumonia (58 %) and Escherichia coli (32 %). In statistical analysis chi square test revealed statistically significant difference (P < 0.05) in percentage of positivity between the two methods (98.66 % vs 100 %). CONCLUSIONS mCIM is highly sensitive and specific method; however, in practice it showed no added advantage over Kirby-Bauer disk diffusion method in detecting CRE. KEYWORDS Modified Carbapenem Inactivation Method (mCIM), Kirby-Bauer Disk Diffusion Method, Carbapenem Resistant Enterobacteriaceae