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Test Code KOHP KOH PREP

Methodology

Direct Microscopic Examination

Useful for determining the presence of fungus in hair, nails, or skin. Cultures are more sensitive than smears; therefore, the KOH prep may be negative when the culture is positive.

Specimen Requirements

Submit only 1 of the following specimens:

 

Hair
Container/Tube: Sterile container(s)
Specimen Volume: 10 to 12 hairs
Collection Instructions:

1. Use a Wood’s lamp during collection, if possible (some infected hairs exhibit fluorescence).
2. Use sterile forceps to pluck 10 to 12 hairs which are broken off or appear diseased.
3. If diseased hair stubs are not apparent, use sterile scalpel to scrape edges of a scalp lesion as follows:
A. Cleanse lesion with 70% isopropyl alcohol.
B. Scrape from outer periphery or border of lesion or involved area.
4. Place specimen in sterile container.
5. Label container with patient’s legal name, date and actual time of collection, and type of specimen.

Note: Specimen source is required.

 

Nails
Container/Tube: Sterile container(s)
Specimen Volume: Generous portion of affected nail and scraping of excess keratin

Collection Instructions:

1. Remove nail polish.

2. Cleanse with 70% isopropyl alcohol.

3. Clip a generous portion of affected nail and obtain scrapings of excess keratin produced beneath nail.

4. Place specimen in sterile container.
5. Label container with patient’s legal name, date and actual time of collection, and type of specimen.

Note: Specimen source is required.

 

Skin
Container/Tube: Sterile container(s)
Specimen Volume: Entire specimen

Collection Instructions:

1. Cleanse lesion with 70% isopropyl alcohol.
2. Scrape from outer periphery or border of lesion or involved area.
3. Place specimen in sterile container.

4. Label container with patient’s legal name, date and actual time of collection, and type of specimen.

Note: Specimen source is required.

Day(s) Test Set Up

Monday through Sunday

Reference Values

No fungal elements seen

Note: Cultures are more sensitive than smears; therefore, the KOH prep may be negative when the culture is positive.

Performing Laboratory

Logan Health Medical Center Laboratory

Test Classification and CPT Coding

87220

Specimen Transport Temperature

Ambient