Test Code Billings Clinic: 6762 Potassium Hydroxide Preparation, Skin

Performing Laboratory

Billings Clinic Laboratory

Potassium hydroxide (KOH) preparation is used to determine the presence of fungus in various sites such as skin, nails, hair, sputum, etc.

1. Cleanse area with 70% alcohol.

2. Scrape skin at active border of lesion.

3. Place into a screw-capped, sterile container.

4. Label container with patient’s name (first and last), date and actual time of collection, and type of specimen.

5. Maintain sterility and forward promptly.
Note: Specimen source is required on request form for processing.

No fungal elements seen
Note: Cultures are more sensitive than smears; therefore, KOH preparation may be negative when culture is positive.

Monday through Sunday

87220