Hair Perforation Test for Dermatophytes

To distinguish between isolates of dermatophytes, particularly Trichophyton mentagrophytes and its variants.

Ingredients:

Autoclaved blonde pre-pubital hair cut into short pieces (1cm)

Sterile distilled water 5 ml in a suitable vial.

Method:

1. Place hair in water in vial.

2. Inoculate with small fragments of the test fungus.

3. Incubate at room temperature.

4. Individual hairs are removed at intervals up to 4 weeks and examined microscopically in lactophenol cotton blue. Isolates of T. mentagrophytes produce marked localised areas of pitting and marked erosion whereas those of T. rubrum do not.