Currentblue cross blue shield - tennesseePolicy N/A

Onychomycosis Testing Coverage Criteria

This policy governs coverage for laboratory and diagnostic tests used to detect or confirm onychomycosis (fungal nail infection) for BlueCross BlueShield of Tennessee members, specifying which tests meet coverage criteria and which do not.

Policy Summary

Payerblue cross blue shield - tennessee

PolicyOnychomycosis Testing Coverage Criteria

Policy CodePolicy N/A

Change TypeNo material changes

Effective DateN/A

Next Review DateN/A

Key ActionUse KOH, fungal culture, or fungal stain first; reserve NAAT only after documented antifungal treatment failure and include supporting clinical documentation.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

3Meets coverage (primary + NAAT after failure)

3Not covered / NMN tests

>15Procedure codes referenced

numerousEvidence references

Coverage Criteria for Onychomycosis Diagnostic Testing

Policy Summary

Payerblue cross blue shield - tennessee

PolicyOnychomycosis Testing Coverage Criteria

Policy CodePolicy N/A

Change TypeNo material changes

Effective DateN/A

Next Review DateN/A

Key ActionUse KOH, fungal culture, or fungal stain first; reserve NAAT only after documented antifungal treatment failure and include supporting clinical documentation.

SourceLink

On This Page

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Primary diagnostic methods: For individuals with signs of onychomycosis, direct microscopic examination with potassium hydroxide (KOH), fungal culture of desquamated subungual material, or fungal stain of a nail clipping(s) MEETS COVERAGE CRITERIA.

Supported by policy statement

NAAT after treatment failure: For individuals with onychomycosis and for whom anti-fungal therapy has failed to resolve infection, nucleic acid amplification testing (NAAT) MEETS COVERAGE CRITERIA.failure of antifungal therapy must be documented

See Note 1 for organisms detectable by NAAT

Not medically necessary / Not covered tests

Not covered diagnostic methods

NAAT for screening/diagnosis: To screen for, diagnose, or confirm onychomycosis, NAAT DOES NOT MEET COVERAGE CRITERIA.

See Note 1 for organisms included in NAAT assays

ATR-FTIR spectroscopy: Attenuated total-reflectance fourier transform infrared (ATR-FTIR) spectroscopy DOES NOT MEET COVERAGE CRITERIA.

Lack of published literature confirming clinical benefit

Fungal-derived sterols testing: Testing for the presence of fungal-derived sterols (e.g., ergosterol) DOES NOT MEET COVERAGE CRITERIA.

Lack of published literature confirming clinical benefit

Consolidated exclusion summary: the following diagnostic methods do not meet coverage criteria for screening, diagnosing, or confirming onychomycosis and are considered not medically necessary: NAAT when used for initial screening or diagnosis, ATR-FTIR spectroscopy, and testing for fungal-derived sterols (e.g., ergosterol). These methods may be denied as they lack sufficient published evidence of clinical benefit for routine diagnostic use.

Provider Requirements, Documentation, and Denial Risks

Prior Authorization

Coding and prior authorization note

Testing that meets the coverage criteria — direct microscopic examination with potassium hydroxide (KOH), fungal culture of desquamated subungual material, or fungal stain of a nail clipping(s) — is covered; NAAT is covered only when used after antifungal therapy has failed to resolve infection. Ensure coding reflects the performed test and documentation supports NAAT after treatment failure to avoid prior authorization denial.

Covered diagnostic methods: KOH microscopy (87220), fungal culture (87101, 87149/87150/87153), fungal stain (88312/87205/87206).
NAAT meets coverage only after documented failure of antifungal therapy (see Note 1 for organisms detectable).

Step Therapy

Step requirement for NAAT

NAAT is allowed to meet coverage criteria only for individuals with onychomycosis when antifungal therapy has failed to resolve the infection, implying that initial diagnostic testing should be KOH, fungal culture, or fungal stain prior to NAAT.

Documented failure of antifungal therapy is required before NAAT meets coverage criteria.

Documentation Required

Required clinical documentation

Document the presence of signs of onychomycosis and the specific diagnostic method used (for example, KOH microscopy, fungal culture of desquamated subungual material, or fungal stain of a nail clipping). If NAAT is performed after antifungal therapy failure, document the prior antifungal treatment and evidence of treatment failure.

Specify which test was performed (KOH, culture, stain, or NAAT) in the clinical record.
If NAAT is used post-treatment, include details of prior antifungal therapy and that it failed to resolve infection.

Denial Risk

Denial risk: NAAT used for initial diagnosis/screening

Claims for NAAT when used to screen for, diagnose, or confirm onychomycosis do not meet coverage criteria and may be denied; NAAT is covered only after documented antifungal therapy failure.

Do not submit NAAT claims for initial screening, diagnosis, or confirmation of onychomycosis.
If NAAT is submitted, ensure documentation demonstrates prior antifungal therapy and treatment failure to support coverage.

Denial Risk

Denial risk: ATR-FTIR and ergosterol testing

Claims for ATR-FTIR spectroscopy and testing for fungal-derived sterols (e.g., ergosterol) do not meet coverage criteria and may be denied due to insufficient published evidence of clinical benefit.

Do not submit claims for ATR-FTIR or ergosterol testing for the screening, diagnosis, or confirmation of onychomycosis.

Relevant Procedure and Billing Codes

Referenced procedure codes (examples)CPT

82542	Column chromatography, includes mass spectrometry, if performed (e.g., HPLC, LC, LC/MS, LC/MS-MS, GC, GC/MS-MS, GC/MS, HPLC/MS), non-drug analyte(s) not elsewhere specified, qualitative or quantitative, each specimen.
87101	Culture, fungi (mold or yeast) isolation, with presumptive identification of isolates; skin, hair, or nail.
87149	Culture, typing; identification by nucleic acid (DNA or RNA) probe, direct probe technique, per culture or isolate, each organism probed.
87150	Culture, typing; identification by nucleic acid (DNA or RNA) probe, amplified probe technique, per culture or isolate, each organism probed.

Additional referenced procedure codesCPT

87153	Culture, typing; identification by nucleic acid sequencing method, each isolate (e.g., sequencing of the 16S rRNA gene).
87205	Smear, primary source with interpretation; Gram or Giemsa stain for bacteria, fungi, or cell types.
87206	Smear, primary source with interpretation; fluorescent and/or acid fast stain for bacteria, fungi, parasites, viruses or cell types.
87220	Tissue examination by KOH slide of samples from skin, hair, or nails for fungi or ectoparasite ova or mites (e.g., scabies).
87480	Infectious agent detection by nucleic acid (DNA or RNA); Candida species, direct probe technique.
87481	Infectious agent detection by nucleic acid (DNA or RNA); Candida species, amplified probe technique.
87482	Infectious agent detection by nucleic acid (DNA or RNA); Candida species.
87798	Infectious agent detection by nucleic acid (DNA or RNA), not otherwise specified; amplified probe technique, each organism.
87800	Infectious agent detection by nucleic acid (DNA or RNA), multiple organisms; direct probe(s) technique.
87801	Infectious agent detection by nucleic acid (DNA or RNA), multiple organisms; amplified probe(s) technique.

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Background on Onychomycosis and Diagnostic Methods

Background: Onychomycosis (tinea unguium) is a fungal infection of the nail most commonly caused by dermatophytes (for example, Trichophyton species), though yeasts and non-dermatophyte molds can also be responsible. Standard diagnostic approaches that meet coverage criteria include KOH microscopic examination, fungal culture of subungual material, and fungal stain of nail clippings. Molecular methods such as NAAT are acknowledged but are only covered in the specific circumstance where antifungal therapy has failed to resolve the infection; NAAT is not covered for initial screening or diagnosis.

Definitions

inv-14: NAAT definition — Nucleic acid amplification testing (NAAT).

DefinitionNucleic acid amplification testing (NAAT): molecular methods that detect and amplify pathogen nucleic acids (e.g., PCR, PCR‑RFLP, next‑generation sequencing) to identify fungal organisms in clinical specimens.

Scope of organisms detectableNAAT assays referenced here can detect Candida species, Aspergillus species, Trichophyton rubrum, Trichophyton mentagrophytes, Epidermophyton floccosum, Neoscytalidium dimidiatum, Onychocola canadensis, Scopulariopsis species, Alternaria species, Acremonium species, and Fusarium species.

Typical clinical useUsed to identify fungal species from nail specimens when organism-level identification is needed; per policy, NAAT meets coverage only after documented failure of antifungal therapy.

Examples of NAAT methodsIncludes polymerase chain reaction (PCR), PCR‑RFLP, and next‑generation sequencing (NGS).

inv-15: Onychomycosis definition — fungal infection of the nail (tinea unguium).

DefinitionOnychomycosis (tinea unguium): a fungal infection of the nail typically caused by dermatophytes but also by yeasts or non‑dermatophyte molds.

Common dermatophyte causesTrichophyton rubrum, Trichophyton mentagrophytes, Epidermophyton flocossum.

Other fungal causesYeasts (e.g., Candida parapsilosis, Candida guilliermondii) and non‑dermatophyte molds (e.g., Neoscytalidium dimidiatum, Onychocola canadensis, Aspergillus species, Scopulariopsis species, Alternaria species, Acremonium species, Fusarium species).