Candidiasis has emerged itself as an alarming opportunistic disease due to increase in the number of immunocompromised, aged, receiving prolonged antibacterial and aggressive cancer chemotherapy or undergoing invasive surgical procedures and organ transplantation patients. Among Candida species, Candida albicans is generally considered as the major pathogen. An increase in the prevalence of non-albicans Candida species has been noted during the last decades. Perry and Miller reported that Candida albicans produces an enzyme b-N-acetyl- galactosaminidase and according to Rousselle et al incorporation of chromogenic or fluorogenic hexosaminidase substrates into the growth medium helps in identification of C. albicans isolates directly on primary isolation. Chromogenic Candida Differential Agar is a selective and differential medium, which facilitates rapid isolation of yeasts from mixed cultures and allows differentiation of Candida species namely C. albicans, C. krusei, C. tropicalis and C. glabrata on the basis of colouration and colony morphology. On this medium results are obtained within 48 hours and it is useful for the rapid and presumptive identification of common yeasts in Mycology and Clinical Microbiology Laboratory.
Peptone and yeast extract provides nitrogenous, carbonaceous compounds and other essential growth nutrients. Phosphate buffers the medium well. Chloramphenicol suppresses the accompaning bacterial flora. C. albicans appear as light green coloured smooth colonies, C. tropicalis appear as blue to metallic blue coloured raised colonies. C. glabrata colonies appear as cream to white smooth colonies, while C.krusei appear as purple fuzzy colonies.