Summary & Overview
CPT 86644: CMV Antibody Immunoassay, Non-IgM
CPT code 86644 represents an immunoassay used to detect antibodies to cytomegalovirus (CMV) in a patient’s blood, explicitly excluding immunoglobulin M (IgM) antibodies. This laboratory test is used clinically to determine past CMV exposure or immune status and has national relevance for prenatal screening, transplant evaluation, and immunocompromised patient management. As a commonly ordered serologic assay, it factors into laboratory utilization, coverage decisions, and diagnostic workflows across payers.
Key payers referenced in the analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. The publication presents what readers need to know about clinical context, billing and coding considerations for CPT code 86644, and payer coverage patterns.
Readers will find benchmarks for utilization and reimbursement where available, summaries of relevant policy updates affecting laboratory testing, and clinical context explaining when a non-IgM CMV antibody assay is used versus other CMV testing. Data limitations are noted where input information is incomplete. The content is written for a national audience and is intended to inform billing professionals, laboratory administrators, and policy analysts about the code’s clinical purpose and payer landscape.
Billing Code Overview
CPT code 86644 describes an immunoassay for cytomegalovirus (CMV) antibodies excluding immunoglobulin M (IgM). The procedure evaluates a patient’s blood for CMV-specific antibodies other than IgM, typically measuring IgG or total non-IgM antibody responses to assess prior exposure or immune status.
Service Type: Laboratory diagnostic test
Typical Site of Service: Clinical laboratory or hospital laboratory
Data not available in the input.
Clinical & Coding Specifications
Clinical Context
A 32-year-old pregnant patient presents for routine prenatal serology screening in the first trimester. The clinician orders a cytomegalovirus (CMV) antibody panel to assess prior exposure and maternal immunity. The laboratory performs an immunoassay to detect CMV-specific immunoglobulin classes other than IgM — typically IgG and total antibody — to determine past infection versus susceptibility. The specimen is a serum sample collected in an outpatient prenatal clinic or hospital outpatient lab. Results are interpreted by the laboratory analyst and reported to the ordering provider; if results suggest recent infection (e.g., low-avidity IgG with concurrent IgM elsewhere), the provider may order follow-up testing. Typical site of service: outpatient laboratory, hospital outpatient department, or physician office-based phlebotomy with courier to a central lab. Service type: laboratory immunoassay for CMV antibodies (non-IgM).
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | When the physician interprets and reports the laboratory result separately from the facility performing the test |
TC | Technical component | When only the laboratory performs the assay and the facility bills for equipment, supplies, and technician time |
90 | Reference (outside) laboratory | When the specimen is sent to an outside reference laboratory for testing |
91 | Repeat clinical diagnostic laboratory test | When a repeat test is performed on the same day to verify prior results |
59 | Distinct procedural service | When another unrelated laboratory or clinical service is performed the same day and must be distinguished |
52 | Reduced services | When the assay is partially performed or a limited/abbreviated panel is run |
53 | Discontinued procedure | When specimen collection or testing was started but discontinued for documented clinical reasons |
76 | Repeat procedure by same provider | When the same laboratory repeats the assay on a different date (note: 76 not in provided list; not selected) |
91 | (Duplicate entry avoided) | (See above) |
| Taxonomy Code | Specialty | Notes |
|---|---|---|
| 261QM0800X | Pathology & Laboratory Medicine | Clinical laboratory directors and pathologists overseeing serologic testing |
| 174400000X | Obstetrics & Gynecology | Ordering clinicians for prenatal CMV screening |
| 207Q00000X | Family Medicine | Primary care or family medicine providers ordering screening tests |
| 363L00000X | Infectious Disease | Specialists requesting confirmatory or follow-up CMV serology |
Related Diagnoses
| ICD-10 Code | Description | Clinical Relevance |
|---|---|---|
O98.512 | Viral disease in pregnancy, cytomegalovirus | Indicates CMV infection complicating pregnancy; warrants maternal CMV serology including non-IgM antibody testing |
Z22.8 | Carrier of other infectious diseases | Used when documenting known exposure or carrier status where CMV serology may be relevant |
Z03.79 | Encounter for suspected maternal infectious disease complicating pregnancy | Used when assessing possible maternal infection, prompting CMV antibody testing |
R75 | Inconclusive laboratory evidence of human immunodeficiency virus [HIV] | Example of an infectious disease-related code often appearing in prenatal serology panels (contextual relevance) |
Z34.90 | Encounter for supervision of normal pregnancy, unspecified trimester | Routine prenatal care encounter during which CMV non-IgM antibody screening may be performed |
Related CPT Codes
| CPT Code | Description | Relationship to This Procedure |
|---|---|---|
86644 | Antibody; cytomegalovirus (CMV), except IgM | Primary immunoassay for non-IgM CMV antibodies (index code) |
86641 | Antibody; cytomegalovirus (CMV), IgM | Performed when acute/recent CMV infection is suspected; used alongside 86644 to assess timing of infection |
86687 | Antibody; Epstein-Barr virus, viral capsid antigen (VCA), IgG | Often ordered in differential viral serology panels for maternal infections |
86789 | Antibody; varicella zoster virus (VZV) | Common prenatal serology performed in the same visit or panel to assess maternal immunity |
80061 | Lipid panel (total, HDL, LDL, triglycerides) | Example of other routine outpatient lab tests that may be ordered during the same phlebotomy visit |