N-methyl-D-Aspartate Receptor Antibody, IgG CBA-IFA, Serum with Reflex to Titer
Ordering Recommendation
Confirm diagnosis of anti-NMDAR encephalitis. May be used in monitoring treatment response in individuals who are antibody positive.
Mnemonic
Methodology
Semi-Quantitative Cell-Based Indirect Fluorescent Antibody
Performed
Sun-Sat
Reported
1-3 days
New York DOH Approval Status
Specimen Required
Serum separator tube.
Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.15 mL)
Refrigerated.
CSF or plasma. Contaminated, hemolyzed, or severely lipemic specimens.
After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)
Reference Interval
Less than 1:10
Interpretive Data
Anti-NMDA receptor IgG antibody is found in a subset of patients with autoimmune limbic encephalitis and may occur with or without associated tumor. Decreasing antibody levels may be associated with therapeutic response; therefore, clinical correlation must be strongly considered. A negative test result does not rule out a diagnosis of autoimmune limbic encephalitis.
This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.
Laboratory Developed Test (LDT)
Note
If NMDA antibody IgG is positive, then an NMDA antibody IgG titer is reported. Additional charges apply.
Hotline History
Hotline History
CPT Codes
86255; if reflexed, add 86256
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
2004222 | N-methyl-D-Aspartate Receptor Ab, Serum | 80221-5 |
Aliases
- Anti-GluN1
- Anti-NMDA
- Anti-NR1
- Glutamate Receptor Antibodies
- N-Methyl D-Aspartate Ab
- NMDA R
- NMDA Receptor Ab
- NMDA Reflex
- NMDA Titer