KOH Mount (10% Potassium Hydroxide Test)





1. Objective

The objective of the test was to detect the presence of fungal elements (hyphae, spores, or yeast cells) in skin scrapings, nail clippings, or hair, confirming superficial fungal infections.

2. Principle

10% Potassium Hydroxide (KOH) was used to dissolve keratin and other tissue elements in the specimen, making fungal structures more visible under the microscope due to their resistance to digestion.

3. Materials

  • 10% Potassium hydroxide (KOH) solution

  • Glass slides and cover slips

  • Specimen (skin scraping, nail, hair)

  • Dropper

  • Forceps, scalpel, or blade

  • Microscope

  • Bunsen burner or warming plate (optional)

4. Procedure

  1. The specimen (e.g., skin scrapings or nail clipping) was placed on a clean glass slide.

  2. A drop of 10% KOH was added to the specimen.

  3. A cover slip was placed over it, and gentle heat was applied if needed to clear keratin quickly.

  4. The preparation was left for 5–15 minutes.

  5. The slide was examined under a microscope (10x and 40x) for fungal elements.

5. Result

  • Positive: Presence of septate or non-septate hyphae, yeast cells, or spores

  • Negative: No fungal elements visible

  • May report morphology:

    • Septate hyphae – Dermatophytes

    • Budding yeast with pseudohyphae – Candida

    • Broad aseptate hyphae – Mucor species

6. Uses

  • Diagnosed dermatophytosis (tinea), onychomycosis, and candidiasis

  • Fast, inexpensive screening method for fungal infections

7. Conclusion

The KOH mount test provided a simple, rapid, and cost-effective method for identifying fungal infections of the skin, hair, and nails through direct microscopy.

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