Dermatology• Updated 21 October 2026
Skin Scraping (KOH) Test
A test where scales from skin, nails or hair are examined to confirm a fungal infection.
Results: Same day to a few weeks (culture) Specimen: Skin, nail or hair scrapings
Quick Summary
Primary Purpose
To confirm ringworm and other fungal infections before treatment.
What It Measures
Fungal threads under the microscope; culture identifies the fungus.
Preparation
Avoid antifungal creams for a few days before if advised.
Overview
KOH dissolves skin cells so fungi are easier to see.
Culture takes longer but identifies the species.
What It Measures
Fungal elements
Seen under the microscope.
How It's Performed
- 01
Scrape
Gently scrape scales with a blade.
- 02
Prepare
Mixed with KOH.
- 03
Examine
Under the microscope.
Interpreting Results & Next Steps
Discuss with Doctor
Your doctor will explain what your result means and what happens next.
If values are High:
Positive results confirm a fungal infection.
Sources and further reading
Last updated 21 October 2026. For more detail, see these trusted health organisations.
- Fungal Culture Test(opens in a new tab) · MedlinePlus, US National Library of Medicine