Hair Perforation Test: Introduction, Requirements, Procedure and Result Interpretation

Introduction of Hair Perforation Test

The hair perforation test is very useful to test for dermatophytes to differentiate Trichophyton and Microsporum species.

Test Requirements for Hair Perforation

• Blade
• Specimen: hair
• Distilled water
• Water vial
• Autoclave
• Microscope
• LPCB stain
• Quality control strains ( Trichophyton  mentagrophytes: Positive while Trichophyton rubrum: Negative)

Test procedure of Hair Perforation Tests

1. Take 10-20 hairs.
2. Cut blonde pre-pubertal hair into short pieces i.e. 1 cm.
3. Autoclave hair at 121 °C for 10 minutes and store in a sterile container.
4. Place 10- 20 short pieces of hair in 5 ml water in a vial.
5. Inoculate with small fragments of the test fungus.
6. Incubate at room temperature.
7. Individual hairs are removed at intervals up to 4 weeks and examined microscopically lactophenol cotton blue (LPCB) stain. Isolates of Trichophyton  mentagrophytes produce marked localized areas of pitting and marked erosion  (wedge-shaped perforations) whereas those of Trichophyton rubrum do not.

Result Interpretation of Hair Perforation Tests

Hair Perforation Test Positive: fungi pierce hair-producing wedge-shaped perforations

Hair Perforation Test Negative: Absence of wedge-shaped perforations

Test: Negative as shown above image below video.

Hair Perforation Test Positive organisms

1. Trichophyton mentagrophytes and
2. Microsporum canis.

Further Reading

1. A Text-Book of Medical Mycology. Editor: Jagdish Chander.  Publication Mehata, India.
2. https://www.science.gov/topicpages/h/hair+perforation+test
3. https://mycology.adelaide.edu.au/laboratory/hair/
4. https://www.researchgate.net/publication/19255784_Evaluation_of_human_hair_sources_for_the_in_vitro_hair_perforation_test