Summary & Overview
CPT 86849: Unlisted Immunology Procedure
CPT code 86849 designates unlisted immunology procedures and is used when a specific immunology test or method lacks an assigned CPT code. Nationally, unlisted procedure codes like 86849 matter because they require additional documentation and justification for medical necessity, which affects claims adjudication, reimbursement timeliness, and clinical-laboratory reporting. Payers commonly require detailed clinical notes, test descriptions, and sometimes pricing comparators when processing claims with unlisted codes.
Key payers covered in this overview include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise explanation of the code’s clinical scope and typical sites of service, guidance on documentation expectations, and a framework for interpreting payer requirements. The publication outlines common modifier usage and administrative considerations associated with unlisted immunology procedures, and describes how 86849 fits into laboratory service lines. The goal is to equip billing staff, laboratory managers, and policy analysts with clear context on when to use CPT code 86849, what documentation payers typically request, and what topics to monitor for policy or reimbursement updates.
Data not available in the input for payer-specific coverage rules, associated taxonomies, and ICD-10 mappings.
Billing Code Overview
CPT code 86849 is an unlisted immunology procedure code used to report immunology services that do not have a specific, established CPT code. It covers miscellaneous immunology laboratory procedures or testing methods that are not described elsewhere in the CPT manual.
Service Type: Immunology laboratory procedures (unlisted)
Typical Site of Service: Clinical laboratory or hospital outpatient laboratory
Clinical & Coding Specifications
Clinical Context
A typical patient is a 45-year-old adult referred to an immunology or laboratory service when standard immunologic assays do not capture an unusual or novel immune marker. The clinician suspects an atypical antibody, immune complex, or specialized cellular immunology finding that requires a non-routine, non-billable-by-specific-code immunology procedure. The workflow begins with clinician documentation of clinical indication (for example, suspected paraneoplastic antibody, uncommon immunodeficiency evaluation, or specialized antigen stimulation testing). The order is placed to a reference or hospital immunology laboratory. The laboratory performs the custom or miscellaneous immunologic technique — such as a novel immunoassay, specialized antigen preparation, or customized flow cytometry panel — and documents the method, results, and interpretation. The laboratory attaches appropriate specimen tracking, test validation notes, and the supervising provider or laboratory director signature. Billing uses 86849 as the miscellaneous immunology procedure code; professional (26) and technical (TC) components may be appended as applicable. Payment review may require submission of method descriptions, test validation data, and medical necessity documentation to payors including Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, BUCA, and Medicare.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|