Summary & Overview

CPT 86480: TB Interferon-Gamma Cell-Mediated Immunity Assay

CPT code 86480 represents a laboratory immunologic assay that measures the gamma interferon antigen response to tuberculosis antigens, evaluating cell-mediated immunity. This test is used clinically to detect immune sensitization to TB and can inform diagnostic pathways for latent or active infection. Nationally, the code matters because TB screening and diagnosis rely on scalable, standardized laboratory methods that affect public health surveillance and clinical management.

Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find an overview of clinical context for the assay, commonly associated sites of service, and the scope of reimbursement considerations across major payers. The publication summarizes available benchmarks, coding guidance, and pertinent policy updates affecting coverage and billing for interferon-gamma release assays.

The report provides practical reference material for billing staff, laboratory managers, and compliance teams by outlining the clinical purpose of the test, typical practice settings, and the payer landscape. Data not available in the input is noted where applicable.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicare86480CPTlaboratoryimmunologytuberculosisinterferon-gammadiagnostic-testinfectious-disease

Billing Code Overview

CPT code 86480 describes a laboratory test performed by a lab analyst to evaluate cell-mediated immunity by measuring the gamma interferon antigen response to tuberculosis (TB) antigens. The service assesses immune system activation specific to TB and aids in identifying prior sensitization or infection.

Service Type: Laboratory diagnostic test, immunologic assay

Typical Site of Service: Clinical laboratory or hospital laboratory

Data not available in the input.

Clinical & Coding Specifications

Clinical Context

A 35-year-old outpatient presents to a primary care clinic for tuberculosis exposure evaluation after close contact with a coworker newly diagnosed with active pulmonary TB. The clinician documents prior Bacillus Calmette–Guérin (BCG) vaccination in childhood and requests an interferon-gamma release assay (IGRA) to assess cell-mediated immune response to Mycobacterium tuberculosis antigens. A phlebotomy technician collects a blood specimen using the manufacturer-recommended tube and timely courier transport is arranged to the reference laboratory. At the laboratory, a trained technologist incubates the specimen with specific TB antigens, measures interferon-gamma release, and reports qualitative/quantitative results. Results are routed back to the ordering clinician for interpretation in the context of risk factors and chest radiography if indicated. Typical site of service is an outpatient clinic, public health clinic, or reference laboratory; specimen collection occurs in clinic and assay performance occurs in the clinical laboratory. Typical patient scenarios include screening of healthcare workers, contacts of active TB cases, asylum seekers or immigrants, and pre-employment or pre-procedural TB screening.

Coding Specifications

Modifier	Description	When to Use
`26`	Professional component	Use when billing only the professional interpretation component if separated from the technical lab component (rare for automated IGRA but applicable when separate professional interpretation is billed).
`59`	Distinct procedural service	Use when the IGRA is performed on a different encounter or distinct from other lab services on the same day that might be bundled.
`91`	Repeat clinical diagnostic lab test	Use when the same IGRA is repeated on the same day for confirmation or device failure.
`90`	Reference (outside) laboratory	Use when the performing laboratory is an outside or reference lab billing for the service.
`TC`	Technical component	Use when billing only the technical component (laboratory processing) and the professional component is billed separately.
`91`	Repeat clinical diagnostic lab test	Use when repeating the assay for verification after an indeterminate result.
`QW`	CLIA waived test	Not typically applicable to IGRA (most IGRAs are moderate complexity); include only if the specific kit is CLIA-waived.
`QK`	CLIA provider performed microscopy (PPM)	Rare for this assay; include only if performed under specific PPM circumstances per payer rules.
`90`	Reference (outside) laboratory	Use when specimen is sent to an outside reference lab and that lab bills for the service.
`91`	Repeat clinical diagnostic lab test	Use for repeats due to unacceptable specimen or indeterminate result.

Taxonomy Code	Specialty	Notes
207Q00000X	Infectious Disease	Specialists who may order and interpret TB testing in complex cases.
208000000X	Pathology & Laboratory Medicine	Pathologists and laboratory directors overseeing assay validation and result reporting.
2085R0200X	Clinical Laboratory	Clinical laboratory scientists and technicians who perform the IGRA.
208D00000X	Family Medicine	Primary care clinicians who commonly order TB screening tests.
207L00000X	Pulmonary Disease	Pulmonologists involved in evaluation of suspected active TB or latent infection.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`Z20.0`	Contact with and (suspected) exposure to tuberculosis	Direct indication for TB screening with an IGRA after known exposure.
`Z11.1`	Encounter for screening for respiratory tuberculosis	Routine screening indication for asymptomatic patients at risk; IGRA commonly used.
`Z11.59`	Encounter for screening for other bacterial diseases	Used when TB screening is part of broader infectious disease screening panels.
`R76.11`	Nonspecific reaction to tuberculin skin test	May prompt use of IGRA to clarify immune response when TST is nonspecific.
`R76.12`	Positive tuberculin skin test reaction	Positive TST may be followed by IGRA for confirmation in some clinical contexts.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`86580`	Skin test; tuberculosis, intradermal (e.g., Mantoux)	Alternative initial screening test for TB; may be used in clinic before or instead of an IGRA.
`87631`	Infectious agent detection by nucleic acid (e.g., M. tuberculosis complex), amplified probe technique, multiple targets	Molecular test used when active TB is suspected; performed on respiratory specimens following a positive screening or clinical concern.
`87481`	Infectious agent antigen detection by immunoassay, multiple-step technique; influenza	Example antigen assay workflow; included as a parallel lab testing code type — not specific to TB but shows typical lab testing sequencing.
`99213`	Office or other outpatient visit for the evaluation and management of an established patient	Common visit code for the clinician encounter during which TB exposure assessment and test ordering occur.
`87070`	Culture, bacterial; any other source, aerobic, with isolation and presumptive identification of isolates	Used when specimen culture is indicated for suspected active TB from nonrespiratory sources; part of the diagnostic cascade for active infection.