Evaluation of Francis media for extended spectrum beta lactamase (ESBL) screening

Abstract

Francis media was developed for the differential screening of Burkholderia pseudomallei. It was later found to have additional function of selecting extended spectrum beta lactamase (ESBL) from Enterobacteriaceae. A total of 305 Enterobacteriaceae isolates from clinical specimens (Klebsiella spp. [191], Escherichia coli [96], Enterobacter spp. [9], Citrobacter spp. [3] and others [6]) were tested for the presence of ESBL.Out of 305, 135 were ESBL producing Enterobacteriaceae tested on Francis media for the presence of yellow colonies and haze after 24 h of incubation. Francis media revealed sensitivity and specificity of 89 and 99%, respectively in detecting ESBL producing Enterobactericeae.