Ordering Recommendation

Use in conjunction with serum autoantibody tests to diagnose neuromyelitis optica (NMO).

Mnemonic
AQP4 CSF
Methodology

Semi-Quantitative Indirect Fluorescent Antibody

Performed

Mon, Wed, Fri

Reported

1-6 days

New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
Collect

CSF.

Specimen Preparation

Transfer 0.5 mL CSF to an ARUP Standard Transport Tube. (Min: 0.15 mL)

Storage/Transport Temperature

Refrigerated.

Unacceptable Conditions

Hemolyzed, contaminated specimens or severely lipemic specimens.

Remarks
Stability

Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year

Reference Interval

less than 1:1

Interpretive Data

Diagnosis of neuromyelitis optica (NMO) requires the presence of longitudinally extensive acute myelitis (lesions extending over 3 or more vertebral segments) and optic neuritis. Approximately 75 percent of patients with NMO express antibodies to the aquaporin-4 (AQP4) receptor. While the absence of AQP4 receptor antibodies does not rule out a diagnosis of NMO, presence of this antibody is diagnostic for NMO.

Compliance Statement B: For laboratory developed tests not using a RUO kit, and for FDA approved, cleared or 510(k) exempt assays with alterations. This test was developed and its performance characteristics determined by ARUP Laboratories. The U. S. Food and Drug Administration has not approved or cleared this test; however, FDA clearance or approval is not currently required for clinical use. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions.

Note

If AQP4 antibody IgG is positive, then an AQP4 antibody IgG titer is reported. Additional charges apply.

Hotline History
N/A
CPT Codes

86255; if reflexed, add 86256

Components
Component Test Code* Component Chart Name LOINC
2011700 Neuromyelitis Optica/AQP4-IgG, CSF 46718-3
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
Aquaporin-4 Receptor Antibody, IgG by IFA, CSF with Reflex to Titer