What Is Koh Test?

The KOH Test for Candida albicans, also known as a potassium hydroxide preparation or KOH prep, is a quick, inexpensive fungal test to differentiate dermatophytes and Candida albicans symptoms from other skin disorders like psoriasis and eczema.

How do you perform a KOH test?

During the Test

The affected skin or nail is gently scraped with a small scalpel or the edge of a glass slide. The scrapings from the skin are placed on a microscope slide and a few drops of a potassium hydroxide (KOH) solution are added. The slide is heated for a short time and then examined under the microscope.

What does a positive KOH test indicate?

Positive results generally indicate that a fungus is present and sometimes identify the type causing an infection: Microscopic examinations (KOH prep or Calcofluor white stain): in general, if fungal elements are seen, then a fungus is the likely the cause of symptoms. These tests, however, do not identify the fungus.