N-methyl-D-Aspartate Receptor (NMDAR) Antibody, IgG by CBA-IFA, Serum With Reflex to Titer
Also known as: NMDA IGG
Use
The N-methyl-D-Aspartate Receptor (NMDAR) Antibody, IgG by CBA-IFA test is utilized primarily for the confirmation of a diagnosis of anti-NMDAR encephalitis. This autoimmune disorder can affect the brain, causing encephalitis, and is characterized by the presence of antibodies against NMDA receptors. The test may also be used for monitoring treatment response in individuals who have tested positive for the antibody. NMDA receptor antibodies are found in patients with autoimmune limbic encephalitis and may occur with or without an associated tumor. Negative test results do not rule out the disease, and testing should be considered in conjunction with other clinical assessments and laboratory findings.
Special Instructions
If NMDA antibody IgG is positive, then an NMDA antibody IgG titer is reported. Additional charges apply for the titration.
Limitations
This test should not be used as the sole basis for diagnosis or patient management decisions. A negative result does not eliminate the possibility of the disease, as antibodies may not always be present in serum. It is recommended to pair serum testing with CSF testing to improve diagnostic sensitivity. Positive results may also be seen in patients with non-autoimmune phenotypes, which could complicate the clinical correlation.
New York Approved
Methodology
Cell-based / Cytometry (Indirect Fluorescent Antibody)
Biomarkers
LOINC Codes
- 80221-5
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.15 mL
Container
ARUP standard transport tube
Collection Instructions
Collect in a serum separator tube or red tube. Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to transport tube.
Storage Instructions
Refrigerated storage recommended.
Causes for Rejection
CSF or plasma. Contaminated, hemolyzed, or severely lipemic specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 48 hours |
| Refrigerated | 2 weeks |
| Frozen | 1 year (avoid repeated freeze/thaw cycles) |