Aquaporin-4 Receptor Antibody by ELISA with Reflex to Aquaporin-4 Receptor Antibody, IgG by IFA
Ordering Recommendation
For evaluation of optic neuritis, acute myelitis, spinal cord lesions, or autoimmune encephalitis.
Methodology
Semi-Quantitative Enzyme-Linked Immunosorbent Assay/ Semi-Quantitative Indirect Fluorescent Antibody
Performed
Tue, Thu
Reported
1-6 days
New York DOH Approval Status
Specimen Required
Serum Separator Tube (SST).
Separate from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.3 mL)
Refrigerated.
Amniotic fluid, CSF, pericardial fluid, ocular fluid, peritoneal fluid, synovial fluid, or plasma. Contaminated, hemolyzed, icteric, or lipemic specimens.
After separation from cells: Ambient: 72 hours; Refrigerated: 2 weeks; Frozen: 1 month (avoid repeated freeze/thaw cycles)
Reference Interval
Test Number |
Components |
Reference Interval |
---|---|---|
Aquaporin-4 Receptor Antibody | 2.9 U/mL or less |
Interpretive Data
Approximately 75 percent 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.
Component | Interpretation | |
---|---|---|
Aquaporin-4 Receptor Antibody | Negative Positive |
2.9 U/mL or less 3.0 U/mL or greater |
FDA
Note
If AQP4 antibody IgG by ELISA is positive, then AQP4 antibody IgG by IFA will be added. If AQP4 antibody IgG by IFA is positive, then an AQP4 antibody IgG titer will be added. Additional charges apply.
Hotline History
Hotline History
CPT Codes
86051; if reflexed, add 86052; 86256
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
2003121 | Aquaporin-4 Receptor Antibody | 68548-7 |