KOH and FUNGUS CULTURE COLLECTION PROCEDURE

KOH Collection:

Acceptable specimens: Fluids, Hair Clippings, Skin Scrapings, and Tissue.

Minimum sample: Collect enough scraping to cover the head of a thumbtack.

Hair

· Scrape the scalp with a blunt scalpel. (Hair stubs, contents of plugged follicles, and skin scales are also acceptable)

· Hair may also be plucked from the scalp with forceps. (Do not submit cut hair.)

· Place in a dry sterile container.

· Transport immediately to the laboratory at room temperature.

Nails

• Cleanse the nail with alcohol.
• Remove the outermost layer by scraping with a scalpel.
• Clippings from any discolored or brittle parts of the nail may be used.
• Deeper scrapings and debris under the edges of the nail are also suitable.
• Place the specimens in a dry sterile container.
• Transport immediately to the laboratory at room temperature.

Skin

• Cleanse the skin with alcohol.
• Collect epidermal scales with a scalpel at the active border of the lesion.
• Place the specimens in a dry sterile container.
• Transport immediately to the laboratory at room temperature.

Fungal Culture Collection:

Scalp and Hair

• Scrape the scalp with a blunt scalpel.
• Collect the basal portion of the infected hair.

Note: Infected hairs may be selected by placing the patient under a UV light (Wood’s lamp).

Hairs infected with some dermatophytes will fluoresce under UV light.

Hairs that are fluorescent, distorted or fractured should be cultured.

• Place hair in a dry sterile container.
• Transport to the laboratory at room temperature.
• The following specimens are also acceptable:

1. Hair stubs

2. Contents of plugged follicles

3. Skin scales

4. Hair plucked from the scalp with forceps.

· The following specimens are not acceptable:

1. Cut hair

Nails

• Cleanse the nail with alcohol.
• Remove the outermost layer by scraping with a scalpel deep enough to obtain recently invaded nail tissue. (discard initial scrapings as they are usually contaminated)
• Place specimen in a dry sterile container.
• Transport to the laboratory at room temperature.
• The following specimens are also acceptable:

1. Clippings from any discolored or brittle parts of nail

2. Deeper scrapings and debris under the edges of the nail

Skin

• Cleanse the skin with alcohol
• With a scalpel or the edge of a glass slide, collect the active, peripheral edge of the lesion.
• Place the scales in a dry sterile container. Collect enough scraping to cover the head of a thumbtack.
• Transport to the laboratory at room temperature.

Other Sources (Submit fluid or culture swab)

1. Bone Marrow – collect 0.5 ml aspirated bone marrow

2. Blood – collect 2 sets of blood cultures (40 ml of blood)

3. Corneal scraping, intraocular aspiration, or biopsy obtained by an ophthalmologist.

4. Sputum – collect first early morning deep cough sample after patient’s teeth are brushed and the mouth is well rinsed (24 hr. specimens are not satisfactory).

5. Subcutaneous Specimens (wound, abscess, lesion, pus, drainage) - For suppurative lesions of the deep skin and subcutaneous tissue, where pus may be loculated within abscess or is exuding from deep sinus tracts, aspiration with a sterile needle and syringe should be attempted. The material should be placed in an anaerobic transport. In addition to a fungus culture, both anaerobic and aerobic cultures should be performed. The former being necessary to recover the anaerobic branching filamentous bacteria belonging to the genus Actinomyces.

6. Tissue – obtained in surgery. Place on sterile 4x4 gauze or in sterile container and transport to the laboratory immediately.

7. Body Fluids and Exudates – samples are usually obtained by aspiration with a sterile needle and syringe.

8. Urine – collect first morning “mid-stream” specimen. Do not obtain urine samples from a collection bag or bedpan.

9. Stool – rarely worth culturing – growth of a large amount of yeast has possible significance, but only in indicating a lack of normal flora.