Test Code LAB7007 Mycology (fungal) culture, hair, skin and nails
Performing Laboratory
Barnes-Jewish Hospital Laboratory
Methodology
Testing algorithm:
Identification of fungi is based on colonial and microscopic morphology, Matrix Assisted Laser Desorption Ionization – Time of Flight Mass Spectrometry (MALDI-TOF MS), and physiologic or biochemical tests, when applicable. Dermatophyte molds are routinely identified from this culture. Suspicious isolates resembling dimorphic fungi are sent to the Mayo Clinic for molecular confirmation, when applicable. When requested, fungal isolates difficult to identify are sent to the University of Texas Science Center at San Antonio, San Antonio, Texas 78229-3900 for identification by combined phenotypic characterization and DNA sequencing of the following targets: ITS,D1/D2.
Specimen Requirements
Acceptable Specimens:
Hair: ≥10 affected hairs with bases of shaft intact
Nail or skin scraping: enough skin or nail scrapings to cover the head of a thumb tack
Collection Procedure:
Hair
1. Aseptically collect ≥10 affected hairs with bases of shaft intact.
2. Place specimen in a leakproof screw-capped, sterile container.
3. Maintain sterility and forward promptly.
4. If transport is delayed, keep specimen at room temperature.
Nails
1. Wipe nail with 70% alcohol. Use gauze (not cotton).
2. Clip away generous portion of affected area, and collect material or debris from under nail.
3. Obtain enough scrapings to cover the head of a thumbtack.
4. Place specimen in a leakproof screw-capped, sterile container.
5. Maintain sterility and forward promptly.
6. If transport is delayed, keep specimen at room temperature.
Skin
1. Thoroughly cleanse affected area with 70% alcohol.
2. Scrape surface of skin at active margin of lesion, do not draw blood (Preferred) or by using an ESwab Collection Kit.
3. Obtain enough scrapings to cover the head of a thumbtack.
4. Place specimen in a leakproof screw-capped, sterile container or return to ESwab transport tube.
5. Maintain sterility and forward promptly.
6. If transport is delayed, keep specimen at room temperature.
Day(s) Test Set Up
Monday through Sunday
Test Classification and CPT Coding
CPT87101 – Hair, skin, and nail culture
Reference Values
No growth of fungi after 14 days
Literature Reference:
Westblade, Lars F. Larone's Medically important fungi - a guide to identification. 7th ed. Washington, DC: American Society for Microbiology; 2023
Specimen Transport Temperature
Ambient/Refrigerate OK
Additional Information
For BJH Laboratory Use Only
Minimum Volume:
Hair: any amount affected hairs with bases of shaft intact in a leakproof screw-capped, sterile container;
Skin scrapings and Nails: enough scrapings to cover the head of a thumbtack in a leakproof screw-capped, sterile container. If ESwab is used - 1 ESwab per test request in sterile transport tube.
Laboratory Processing Instructions:
Test performed in BJH Microbiology.