Fungal culture and smear - Dermal (hair, skin and nail)




Test Mnemonic

FHSNSM

CPT Codes

  • 87176 - QTY (1)
  • 87118 - QTY (1)
  • 87077 - QTY (1)
  • 87106 - QTY (1)
  • 87107 - QTY (1)
  • 87153 - QTY (1)
  • 87181 - QTY (1)
  • 87184 - QTY (1)
  • 87185 - QTY (1)
  • 87186 - QTY (1)
  • 87186 - QTY (1)
  • 87186 - QTY (1)
  • 87186 - QTY (1)
  • 87101 - QTY (1)
  • 87206 - QTY (1)

Aliases

  • Dermal
  • Dermatophyte
  • Fungal culture
  • Fungal stain
  • Fungus culture
  • Mycology
  • Ringworm
  • Tinea
  • Calcofluor Smear
  • Dermatophyte Culture
  • Fungal Culture Dermal
  • Fungal Smear
  • KOH Smear
  • Mold Culture
  • Yeast Culture

Includes

  • Specimens may include some pre-processing steps to aid in recovery of fungal organisms.

Performing Laboratory

n/a


Specimen Requirements

Volume Type Container Collect Temperature Transport Temperature Special Instructions
Entire collectionHairSterile container AmbientHair root is essential for the recovery of fungal organisms so plucking or pulling hair with intact hair shaft is ideal. Cutting hair is not recommended. In cases of alopecia (hair loss), hair can be collected from the region by using a soft bristle toothbrush and rubbing in circular motions over the margins or patches. Collected specimens should be sent in a sterile container or dry paper envelope. Ensure that the specimen is secured within the container to prevent loss of specimen. Specimen should be transported dry in ambient temperatures for optimal recovery.
Entire collectionSkinSterile container AmbientThe affected area should be cleaned with70% alcohol and allowed to dry. Skin should be scraped with a dull edged object or vigorously brushed in a circular motion with a toothbrush. Be careful to not draw blood. Leading edge of the skin lesion is the preferred sample for optimal recovery of fungal organisms. Ensure that the specimen is secured within the container to prevent loss of specimen. Specimen should be transported dry in ambient temperatures for optimal recovery.
Entire collectionNailsSterile container AmbientNails should be cleaned with 70% alcohol and then clipped or scraped with a scalpel. Clip generous portion of the affected area and place in sterile container along with any material or debris from under the nail/nailbed. Ensure that the specimen is secured within the container to prevent loss of specimen. Specimen should be transported dry in ambient temperatures for optimal recovery.

Stability

Environmental Condition Description
Ambient7 days
Refrigerated7 days
FrozenUnacceptable

Days Performed

Sun - Sat

Turnaround Time

6 weeks

Methodology

Name Description
Culture 
Stain 

Reference Range

Fungal Culture
Sex Age From Age To Type Range Range Unit
       No fungal growth 
Fungal Smear
Sex Age From Age To Type Range Range Unit
       No fungus seen 

Special Info

Fungal smears are performed directly on specimen using a Calcofluor white stain that nonspecifically binds chitin in the cell wall of fungi. Fluorescent microscopy is utilized to detect and report as yeast and/or hyphae present. CPT code: 87206. Clinical specimens for dermal fungal cultures are processed and plated on selective fungal media to optimize recovery of fungal organisms. Cultures are incubated for 28 days; negative results are auto-updated daily. Any fungal organisms recovered will be isolated and identified by various methods. Additional CPT codes may be applicable for recovery and identification of fungal organisms 87106 - ID by MALDI-TOF Mass Spec for yeast, 87107 - ID by MALDI-TOF Mass Spec for Mold, 87153 - DNA sequencing. Fungal susceptibility testing for yeast and filamentous mold recovered is ONLY performed by request when clinically relevant (CPT 87186). Yeast susceptibility testing is performed in-house by colorimetric microdilution broth. A standardized inoculation of test organism is incubated with appropriate dilutions of antifungal agents; minimum inhibitory concentration (MIC) are determined by inhibition of growth at the lowest antifungal concentration. MIC are determined and interpreted according to CLSI standards. Filamentous mold susceptibility testing is a send-out test and can be requested by contacting the lab.

Clinical Info

Aseptic technique should be utilized to minimize contamination and for optimal recovery of organisms. Specimen should be transported immediately to the microbiology laboratory in dry conditions at ambient temperatures. Refrigeration may impact recovery of dermatophytes. Isolation and identification of fungi from keratinized tissue such as hair, skin and nails are commonly due to dermatophytic fungi. Opportunistic superficial infections caused by other fungal organisms and yeasts resembling dermatophytoses will also be identified and reported. However, normally saprophytic or environmental fungi are often recovered from these sites. Clinical correlation with patient symptoms is necessary to determine significance of recovered organism. If specific fungi are suspected the "rule out" feature in Epic can be utilized. If fungal smears are needed order FCULSM; for fungal blood cultures HISTCL; for CSF order FUNCSF; for dermal samples of hair, skin and nail order ACFSC or FHSNSM (with smear); for candidiasis on vaginal and oral samples order fungal screen FUNGSC. If culture only (without smear) is desired, order ACFSC - Fungal Culture Hair, Skin, Nail.

Clinical Limitation

Not all fungal organisms recovered in cultures may be significant; clinical correlation needed to determine significance.

Clinical Reference

Westblade et. al. Larone’s Medically Important Fungi, 7th edition, ASM press, Washington DC., 2024. Leber et al., Clinical Microbiology Procedures Handbook, 5th edition, ASM press, Washington, DC. 2023. Carroll, et al. Manual of Clinical Microbiology, 13th Edition, Volume 3, ASM Press, Washington, DC. 2024.