Myopathy: Selected Tests — CPB 0862 | AETNA Coverage Update

Aetna modified CPB 0862 covering myopathy selected tests, effective January 5, 2026. Here's what billing teams need to know about anti-HMGCR antibody testing coverage and eight newly classified experimental tests.

Aetna, a CVS Health company, updated CPB 0862 to define precise medical necessity criteria for anti-HMGCR antibody testing (billed under CPT 83520) in statin-associated autoimmune myopathy. The updated Aetna myopathy coverage policy also expands the experimental and investigational list to eight specific tests — including D-dimer panels (CPT 85378, 85379) and pyrophosphate muscle scans (HCPCS A9538) — that Aetna will not cover for myopathy-related indications. If your practice sees patients with drug-induced myopathy (G72.0) or inflammatory myopathies, this update changes how you document and bill these cases.

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Quick-Reference Table

Field	Detail Copy
Payer	Aetna, a CVS Health company
Policy	Myopathy: Selected Tests
Policy Code	CPB 0862
Change Type	Modified
Effective Date	January 5, 2026
Impact Level	Medium
Specialties Affected	Neurology, Rheumatology, Internal Medicine, Clinical Laboratory
Key Action	Audit charge capture for CPT 83520 to confirm documentation meets all three anti-HMGCR criteria before billing; stop billing CPT 85378, 85379, and HCPCS A9538 for myopathy indications

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Aetna Myopathy Coverage Criteria and Medical Necessity Requirements 2026

The centerpiece of this update is anti-HMGCR antibody testing. CPB 0862 Aetna now defines this as medically necessary — but only when all three of the following conditions are met simultaneously.

First, the patient must have been exposed to statins. Second, the patient must have myalgias and a creatinine kinase (CK) level greater than 10 times the upper limit of normal. Third, those symptoms must persist for two months after statin discontinuation — or less than two months if the patient's symptoms are progressing.

That third criterion is doing a lot of work. Aetna is essentially saying: if CK stays elevated and myalgias continue for 60 days post-statin, you can bill CPT 83520 (immunoassay, quantitative) and expect coverage. But if you order the test at week three post-discontinuation because your clinical instinct says this is autoimmune — and symptoms aren't clearly worsening — expect a claim denial.

The real issue here is documentation timing. Your chart needs to show the statin exposure history, the CK value with the lab reference range, and the date of statin discontinuation. Without all three, you don't have a defensible medical necessity argument under this coverage policy.

Reimbursement for CPT 83520 under this policy only flows when the criteria are met exactly. Document before you order, not after.

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Aetna Myopathy Exclusions and Non-Covered Indications

This is where the update gets operationally significant. Aetna now explicitly classifies eight tests as experimental, investigational, or unproven for myopathy-related indications.

Some of these will catch practices off guard. D-dimer testing — CPT 85378 (qualitative/semiquantitative) and CPT 85379 (quantitative) — is a routine lab test used across many specialties. But billing it under a myopathy diagnosis for evaluation of inflammatory myopathies is now a coverage dead end with Aetna. Same story for HCPCS A9538, the Technetium Tc-99m pyrophosphate used in pyrophosphate muscle scans.

The full experimental list under CPB 0862:

A few things worth calling out here. The anti-NXP2 antibody exclusion is notable because anti-NXP2 is a legitimate myositis-specific antibody with clinical utility. Aetna's position is that evidence for its use specifically in immune-mediated necrotizing myopathy hasn't met the bar. If your rheumatologists order this regularly, flag it. If they want myositis antibody panels covered, CPB 0866 (Rheumatic Diseases: Selected Tests) is the relevant policy — not CPB 0862.

Similarly, if your team has been using low-dose CT to track calcifications in juvenile idiopathic inflammatory myopathy, stop expecting Aetna reimbursement. The policy is clear: that indication is experimental.

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Coverage Indications at a Glance

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Aetna Myopathy Billing Guidelines and Action Items 2026

Act on these before January 5, 2026 — or immediately if you're reading this after the effective date.

Copy Action Items

Note: CPB 0862 does not address prior authorization. If your Aetna plans require prior auth on specialty lab — which varies by plan type — verify those requirements through Aetna's plan-level benefits. That's general billing practice, not a finding from this policy.

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CPT, HCPCS, and ICD-10 Codes for Myopathy Selected Tests Under CPB 0862

Covered CPT Codes (When Selection Criteria Are Met)

Code	Type	Description Copy
83520	CPT	Immunoassay for analyte other than infectious agent antibody or infectious agent antigen; quantitative

Not Covered / Experimental Codes

Key ICD-10-CM Diagnosis Codes

The following ICD-10-CM codes appear in CPB 0862. This is a representative set — the full policy lists 135 codes. Review the complete list at the source policy before finalizing your charge capture mapping.

Note: The policy includes the full M33.x code family (M33.0 through M33.9x), covering dermatomyositis and polymyositis with extensive subcodes for organ involvement. Pull the complete ICD-10 list from the source policy at CPB 0862 on Aetna's Clinical Policy Bulletins before updating your billing system.

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