This study was done to detect extended spectrum β –lactamases (ESBL) in Coliforms from various clnical samples collected in the department of Microbiology laboratory ,Government Medical College Kozhikode. A total of 150 samples were tested for ESBL,100 were of found to bepositive by double disk synergy test;out of these 100 strains, E.coli were  55% and K.pneumonia were 45%.. Imipenem appears to be the drug of choice for serious infections confirmed to be caused by ESBLs.

Keywords: Double disk synergy test, Beta lactamases, Enterobacteriaceae.

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Dr Mini Palathingal Narayanan

Associate Professor in Microbiology,

Govt Medical College, Kozhikode