Gram-negative bacteria (GNB), particularly Enterobacteriaceae are a major cause of healthcare-associated infection. More over Infections caused by resistant organisms result in a tremendous morbidity and mortality worldwide. In the last few years carbapenem resistant gram-negative organisms have become a serious threat to cancer patients. The objective of this study is to detect the prevalence of MBL producers in various clinical samples by phenotypic methods. This is hospital based cross-sectional study. A total of 110 GNB isolates from various clinical samples were included in the study. Phenotypic detection of Metallo ß-lactamases (MBLs) was carried out by Modified Hodge test (MHT) and Disc Potentiation test (DPT). Out of 110 GNB isolates, E. coli was the predominant species (n = 45), followed by K. pneumoniae (n = 37) and P. aeruginosa (n = 16) K. pneumoniae (n = 11; 28%) showed maximum production of MBL by phenotypic methods. The study underlines the problem of MBL mediated resistance, which has created a therapeutic challenge for the clinicians and microbiologists. Simple disc diffusion methods can be routinely employed to detect these common resistance mechanisms which will reduce the mortality and also spread of such resistant strains.

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