In recent years, carbapenem resistance has emerged in Klebsiella pneumoniae (K. pneumoniae) isolates due to acquisition of different carbapenemases enzyme. Carbapenemase producing bacteria are often misidentified by routine microbiological susceptibility testing and incorrectly reported as sensitive to carbapenems; however, resistance to the antibiotic ertapenem is common and a better and sensitive indicator of Carbapenem resistance. Routine laboratory detection of carbapenemase producing K. pneumoniae isolates is crucial, both for a therapeutic management and an efficient infection control. The present study was under taken to assess the evaluation of different phenotypic methods in detection of K. pneumoniae Carbapenemase (KPC). All clinical isolates of K. pneumoniae was collected from December 2014 to November 2016 was included in the study. Urine, Pus, ET secretions, BAL, Blood and other Body fluids received in the laboratory were subjected to routine processing as per standard operating procedures. Antimicrobial susceptibility testing was performed as per the CLSI guidelines (2013) by Vitek2 automated system to detect carbapenem resistant K. pneumoniae (CRKP) as primary test. Further, confirmatory test was carried by Modified Hodge test, HiCrome Agar KPC test and Carba NP test as different phenotypic tests. Total of 1,539 Klebsiella pneumoniae were isolated from various clinical samples. Only, 254 (16.50%) isolates were carbapenem resistant K. pneumoniae (CRKP). In which, 184 (72.44%) were positive with clover-leaf indentation for Modified Hodge Test (MHT) followed by 235 (92.51%) were positive for HiCrome KPC agar test and 239 (94.09%) were positive (Color change within 2hrs of incubation from red to orange/yellow color) for Carba NP test. Among the different phenotypic tests conducted, Carba NP test showed 239(94.09%) were positive, which was rapid (<2 hours), inexpensive technique compared to HiChrome agar KPC test and Modified hodge test. This technique can be implemented in any laboratory for early detection of Carbapenem resistance (CR).

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