Dermatophyte Test Medium with Chloramphenicol (500mg/L)
Dermatophyte Test Medium is a selective medium for the isolation of dermatophytes from hair, skin etc. and is based on a modification of the original formulation of Taplin, Zaias, Rebell and Blank. Although the low pH (5.5) of the medium inhibits most bacteria, Chloramphenicol is added to further reduce the risk when processing material that may be more heavily contaminated particularly with organisms of the coliform group. The inclusion of Phenol Red indicator assists in differentiation between saprophytic and environmental fungi. Dermatophytes appear as fluffy colonies with reddening of the medium while other fungi cause the medium to become yellow due to acid production. Yeasts will also grow on this medium but are readily distinguished by their distinct white/creamy colonies and distinctive smell.
NB: Prolonged incubation should be avoided as this may cause fungi other than dermatophytes to turn the medium red