Summary & Overview

CPT 86053: Aquaporin-4 Antibody Test by FACS

CPT code 86053 denotes a laboratory assay for the aquaporin-4 antibody using fluorescence-activated cell sorting (FACS) on serum, a diagnostic marker for neuromyelitis optica (NMO). This immunologic test has national clinical importance because a positive result supports diagnosis of NMO and guides neurologic management distinct from multiple sclerosis. Coverage and payment for specialized serologic testing like this vary across payers and influence access to targeted therapies and diagnostic certainty.

Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of clinical context for the assay, typical service setting, and what payers commonly consider when adjudicating claims for specialized antibody testing. The publication also outlines expected benchmarks and policy-relevant considerations for lab-based immunologic testing, aiding billing, coding, and compliance teams in understanding where this code fits into laboratory service lines. Data not available in the input for detailed associated taxonomies, ICD-10 pairings, and related codes.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicare86053CPTaquaporin-4neuromyelitis-opticaFACSflow-cytometrylaboratoryserology

Billing Code Overview

CPT code 86053 describes a laboratory test that detects an antibody to aquaporin-4 in a serum specimen using fluorescence-activated cell sorting (FACS) with flow cytometry. The test identifies the presence of aquaporin-4 antibody, a key marker for neuromyelitis optica (NMO), an autoimmune inflammatory disorder that primarily affects the optic nerve and can involve the brainstem and spinal cord and is sometimes misdiagnosed as multiple sclerosis.

Service Type: Laboratory — immunologic serology test performed via flow cytometry (FACS)

Typical Site of Service: Clinical laboratory or hospital laboratory

Data not available in the input for Associated Taxonomies, ICD-10 Diagnoses, and Related Codes.

Clinical & Coding Specifications

Clinical Context

A 36-year-old woman presents to neurology with subacute bilateral optic neuritis and longitudinally extensive transverse myelitis characterized by visual loss, painful eye movements, and ascending sensory changes. Prior evaluation raised concern for demyelinating disease; neuromyelitis optica spectrum disorder (NMOSD) is suspected. The treating neurologist orders serum testing for the aquaporin-4 (AQP4) antibody by fluorescence-activated cell sorting (FACS) using flow cytometry, billed with 86053.

Specimen collection is venous blood drawn into a serum tube during the clinic visit or at an outpatient laboratory. The sample is shipped to a clinical immunology laboratory where technologists perform a FACS-based assay to detect AQP4-IgG. Results are reported to the ordering neurologist and incorporated into the diagnostic workup to distinguish NMOSD from multiple sclerosis and guide disease-modifying therapy decisions. Typical payer interactions occur through professional and technical component billing when applicable, and reflex testing or repeat testing may be ordered if clinical correlation is needed.

Coding Specifications

Modifier	Description	When to Use
`26`	Professional component	Use when billing only the physician or professional interpretation component separate from the laboratory technical component.
`TC`	Technical component	Use when billing only the laboratory technical component (equipment, technician, reagents) and not the professional interpretation.
`90`	Reference (outside) lab	Use when the test is performed by an outside/contract laboratory on behalf of the billing provider.
`91`	Repeat clinical diagnostic laboratory test	Use when a repeat test is performed on the same day for monitoring or verification.
`59`	Distinct procedural service	Use when another distinct service is performed on the same day that is not typically bundled with the laboratory service (rare for standalone lab codes).
`52`	Reduced services	Use when the lab test is partially reduced or not performed to its full extent.
`53`	Discontinued procedure	Use when specimen collection or testing was initiated but discontinued for clinical reasons.
`62`	Two surgeons (applicable contextually)	Rarely applicable; used when two qualified providers share responsibility for interpretation in complex cases.
`90`	Reference (duplicate entry removed)	Duplicate entries are not listed twice.
`QW`	CLIA-waived test	Not applicable to `86053` (FACS is non-waived); include only when billing a waived method.

Taxonomy Code	Specialty	Notes
2084P0800X	Neurology	Ordering and interpreting clinicians for antibody testing in demyelinating disease.
207RC0000X	Clinical Pathology	Laboratory directors overseeing immunology and serology testing.
207KP0008X	Clinical Laboratory	Clinical laboratory scientists/medical technologists performing FACS assays.
261QM0700X	Immunology	Clinical immunologists or neuroimmunologists involved in interpretation and clinical correlation.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`G36.0`	Neuromyelitis optica (Devic disease)	Primary diagnosis for which AQP4 antibody testing by `86053` is performed to confirm NMOSD.
`H46.9`	Optic neuritis, unspecified	Presentation prompting AQP4 antibody testing when optic neuritis raises concern for NMOSD versus MS.
`G37.3`	Acute transverse myelitis in demyelinating disease of central nervous system	Spinal cord involvement that prompts AQP4 testing to evaluate for NMOSD.
`G35`	Multiple sclerosis	Differential diagnosis; AQP4 testing helps distinguish NMOSD from MS.
`G04.89`	Other encephalitis, myelitis and encephalomyelitis	Broader inflammatory CNS disorders where AQP4 testing may be clinically considered.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`36415`	Collection of venous blood by venipuncture	Specimen collection for serum used in `86053`.
`85025`	Blood count; automated	Often ordered concurrently to assess general hematologic status prior to immunologic testing.
`86336`	Immunoassay for infectious agent antibody(ies), qualitative or semiquantitative, single step method; e.g., ELISA	Alternative antibody detection methods that may be ordered in different laboratories if FACS is not available.
`88360`	Immunohistochemistry, per specimen; initial single antibody stain	Occasionally used when tissue-based antibody studies or confirmatory testing are performed in complex diagnostic workflows.
`99000`	Handling and/or conveyance of specimen	Applied in some payer scenarios for special handling or shipment to a reference lab performing `86053`.