ARUP's Laboratory Test Directory

Aquaporin-4 Receptor Antibody : 2003036
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Additional Technical Information
  


Mnemonic: AQP4

Ordering Recommendation: Aids in evaluation of neuromyelitis optica (NMO) and NMO spectrum disorders.
Methodology: Semi-Quantitative Enzyme-Linked Immunosorbent Assay
Performed: Tue
Reported: 1-8 days
Specimen Required: Collect: Serum separator tube.

Specimen Preparation: Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.3 mL)

Storage/Transport Temperature: Refrigerated.

Unacceptable Conditions: CSF, amniotic fluid, ocular fluid peritoneal fluid, synovial fluid, or plasma. Contaminated, hemolyzed, icteric, or lipemic specimens.

Stability (collection to initiation of testing): After separation from cells: Ambient: 72 hours; Refrigerated: 2 weeks; Frozen: 1 month (avoid repeated freeze/thaw cycles)
Reference Interval:
Negative: 4 U/mL or less
Indeterminate: 5 U/mL
Positive: 6 U/mL or greater
Interpretive Data: Approximately 75% of patients with neuromyelitis optica (NMO) express antibodies to the aquaporin-4 (AQP4) receptor. Diagnosis of NMO requires the presence of longitudinally extensive acute myelitis (lesions extending over 3 or more vertebral segments) and optic neuritis. While absence of antibodies to the AQP4 receptor does not rule out the diagnosis of NMO, presence of this antibody is diagnostic for NMO.

See Compliance Statement D: www.aruplab.com/CS
CPT Code(s): 83516
Cross References: AQP (Aquaporin-4 Receptor Antibody), Devic's Ab (Aquaporin-4 Receptor Antibody), Neuromyelitis Optica (NMO) Antibody (Aquaporin-4 Receptor Antibody), Optic Neuritix Ab (Aquaporin-4 Receptor Antibody), Optic-Spincal MS Ab (Aquaporin-4 Receptor Antibody), Soft-NMOS (Aquaporin-4 Receptor Antibody), Transverse Myelitis Ab (Aquaporin-4 Receptor Antibody), Vision Loss Ab (Aquaporin-4 Receptor Antibody)