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    v1.0.28
    OpenPayerPolicy UpdatesDermatologyAmbetter Nevada onychomycosis lab Coverage Update …
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    CurrentAmbetter NevadaPolicy N/A

    Onychomycosis diagnostic testing (laboratory)

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    Outpatient clinical policy governing laboratory testing to confirm suspected onychomycosis (microscopy/peroxidase, fungal culture, and molecular NAAT/PCR) and who may receive these tests before antifungal therapy.

    Policy Summary
    PayerAmbetter Nevada
    PolicyOnychomycosis diagnostic testing (laboratory)
    Policy CodePolicy N/A
    Change TypeRevision (wording clarificationcoding reorganization)
    Effective DateN/A
    Last ReviewMar 24, 2023
    Next Review DateN/A
    Key ActionDocument clinical signs or symptoms of onychomycosis and show that test results will influence management before ordering laboratory testing.
    SourceLink

    OpenPayer is powered by Trek Health's payer performance platform. Trek continuously ingests, validates, and normalizes Transparency in Coverage data alongside payer policies and other commercial payer data to create a structured payer intelligence foundation. OpenPayer uses this foundation to deliver personalized search results, dynamically generated policy pages, and tailored policy monitoring based on each user's payers, specialties, billing codes, and areas of interest. The same intelligence powers broader payer performance workflows, including reimbursement benchmarking, contract evaluation, payer negotiations, and financial decision-making.

    POLICY UPDATE CHANGES

    For Fungal Culture for Onychomycosis and Microscopy/Peroxidase Tests for Onychomycosis, policy statements were reworded from 'may be considered medically necessary' to 'are considered medically necessary.'

    Added CPT code table and moved the 'coding implications' section.

    Added 'Lab' to policy title and removed CPT and ICD-10 codes from the policy reference table.

    3test types addressed
    >=1clinical signs required
    MultipleCPT codes listed
    Yesguideline-cited

    Coverage Criteria for Onychomycosis Diagnostic Testing

    Microscopy/Peroxidase Tests for Onychomycosis

    Microscopy/peroxidase tests are considered medically necessary when ALL of the following are met:

    Microscopy criteria: A. The member/enrollee shows signs or symptoms of onychomycosis (e.g., nails that are discolored, deformed, brittle, and/or foul-smelling; subungual debris; separation of the nail from the nail bed).

    Document signs/symptoms; testing may be denied if absent.

    Management impact: B. Results of testing would influence the member/enrollee's clinical management.

    If not met, current evidence does not support use.

    Fungal Culture for Onychomycosis

    Fungal culture (presumptive and/or definitive) is considered medically necessary when ALL of the following are met:

    Culture criteria: A. The member/enrollee shows signs or symptoms of onychomycosis (e.g., nails that are discolored, deformed, brittle, and/or foul-smelling; subungual debris; separation of the nail from the nail bed).

    Document signs/symptoms; testing may be denied if absent.

    Management impact: B. Results of testing would influence the member/enrollee's clinical management.

    If not met, current evidence does not support use.

    Culture-Independent Molecular Tests (NAAT/PCR) for Onychomycosis

    Coverage stance:

    NAAT/PCR stance: Current evidence does not support the use of culture-independent molecular tests (NAAT/PCR) for onychomycosis for all indications.

    No clinical criteria provided to support routine use.

    The policy's coverage stance for culture-independent molecular testing is that current evidence does not support the use of culture-independent molecular tests (NAAT/PCR) for onychomycosis for all indications. No clinical criteria are provided in this policy to support routine use of NAAT/PCR testing for diagnosis or management of onychomycosis.

    Use of laboratory tests—microscopy/peroxidase, fungal culture (presumptive and/or definitive), or culture-independent molecular (NAAT/PCR) testing—outside the specific indications stated in this policy is not supported by current evidence. Specifically, testing is supported only when the member shows signs or symptoms of onychomycosis and when test results would influence clinical management; otherwise these tests are not supported.

    Coding and Billing (CPT Codes)

    Fungal culture and identification CPT codesCPT
    87101Culture, fungi (mold or yeast) isolation, with presumptive identification of isolates; skin, hair, or nail.
    87102Culture, fungi (mold or yeast) isolation, with presumptive identification of isolates; other source (except blood).
    87106Culture, fungi, definitive identification, each organism; yeast.
    87107Culture, fungi, definitive identification, each organism; mold.
    Microscopy/KOH and culture-typing CPT codesCPT
    87143Culture, typing; gas liquid chromatography (GLC) or high pressure liquid chromatography (HPLC) method.
    87147Culture, typing; immunologic method, other than immunofluorescence (eg, agglutination grouping), per antiserum.
    87149Culture, typing; identification by nucleic acid (DNA or RNA) probe, direct probe technique, per culture or isolate, each organism probed.
    87150Culture, typing; identification by nucleic acid (DNA or RNA) probe, amplified probe technique, per culture or isolate, each organism probed.
    87206Smear, primary source with interpretation; fluorescent and/or acid fast stain for bacteria, fungi, parasites, viruses or cell types.
    87220Tissue examination by KOH slide of samples from skin, hair, or nails for fungi or ectoparasite ova or mites (eg, scabies).
    Molecular/NAAT CPT codesCPT
    87480Infectious agent detection by nucleic acid (DNA or RNA); Candida species, direct probe technique.
    87481Infectious agent detection by nucleic acid (DNA or RNA); Candida species, amplified probe technique.
    87482Infectious agent detection by nucleic acid (DNA or RNA); Candida species, quantification.
    87798Infectious agent detection by nucleic acid (DNA or RNA), not otherwise specified; amplified probe technique, each organism.
    87799Infectious agent detection by nucleic acid (DNA or RNA), not otherwise specified; quantification, each organism.
    87800Infectious agent detection by nucleic acid (DNA or RNA), multiple organisms; direct probe(s) technique.
    87801Infectious agent detection by nucleic acid (DNA or RNA), multiple organisms; amplified probe(s) technique.

    Provider Actions, Documentation, and Prior Authorization Notes

    Prior Authorization

    Verify coding and prior-authorization requirements

    Some laboratory CPT codes are provided for informational purposes only; verify coding and prior-authorization requirements with the payer before submitting claims. CPT listings in this policy are not all‑inclusive and inclusion or exclusion does not guarantee coverage.

    • Codes referenced are informational; reference current professional coding guidance prior to claim submission.
    • Inclusion/exclusion of codes herein does not guarantee coverage.
    Step Therapy

    No step therapy required

    This policy specifies no step therapy requirements for diagnostic testing of suspected onychomycosis.

    Background

    Onychomycosis is a common fungal infection of the nails, more often affecting toenails than fingernails, and typically presents with nail discoloration, splitting or deformation, increased brittleness, and sometimes involvement of the surrounding skin. Because several non-fungal conditions can mimic onychomycosis, confirmatory laboratory testing is recommended before initiating antifungal therapy in the outpatient setting.

    Definitions

    Onychomycosis (definition)
    DefinitionFungal infection of the nails presenting with discoloration, splitting, deformation, brittleness, and potential involvement of surrounding skin.
    Typical siteMore commonly affects toenails than fingernails.
    Clinical mimicsNon-fungal infections and non-infectious nail conditions (e.g., nail dystrophy) can mimic onychomycosis; confirmatory testing is recommended before treatment.
    Testing implicationConfirmatory laboratory testing (microscopy/KOH, culture, or molecular methods) should be performed prior to initiating antifungal therapy to avoid inappropriate use.
    KOH preparation (microscopy)
    TechniquePotassium hydroxide (KOH) preparation is a direct microscopy technique that examines nail samples for fungal elements.
    Policy Summary
    PayerAmbetter Nevada
    PolicyOnychomycosis diagnostic testing (laboratory)
    Policy CodePolicy N/A
    Change TypeRevision (wording clarificationcoding reorganization)
    Effective DateN/A
    Last ReviewMar 24, 2023
    Next Review DateN/A
    Key ActionDocument clinical signs or symptoms of onychomycosis and show that test results will influence management before ordering laboratory testing.
    SourceLink
    On This Page
    Coverage Criteria for Onychomycosis Diagnostic TestingCoding and Billing (CPT Codes)Provider Actions, Documentation, and Prior Authorization NotesBackgroundDefinitions
    Documentation Required

    Required documentation of signs/symptoms and management impact

    Document that the member shows clinical signs or symptoms of onychomycosis and that test results will influence clinical management.

    • Examples of signs/symptoms to document: discolored, deformed, brittle, and/or foul‑smelling nails;
    • subungual debris; separation of the nail from the nail bed;
    • Rationale that test results will influence treatment decisions (e.g., to confirm fungal infection before antifungal therapy).
    Denial Risk

    Denial triggers for testing

    Testing may be denied when the member lacks signs or symptoms of onychomycosis or when results would not influence clinical management.

    • Use of microscopy, fungal culture, or molecular NAAT/PCR outside the stated indications is not supported by current evidence and may be denied.
    Preferred methodKOH preparation with direct microscopy is the preferred diagnostic method because it is highly specific, provides rapid results, and is cost-effective.
    Clinical useA positive KOH preparation alone is sufficient to initiate treatment; if KOH is negative but clinical suspicion remains high, additional testing may be performed.
    LimitationsKOH may be negative when clinical suspicion is high; in such cases, culture or molecular testing can be considered to confirm diagnosis.