N-methyl-D-Aspartate Receptor Antibody, IgG




Test Mnemonic

NMDAG

CPT Codes

  • 86255 - QTY (1)

Aliases

  • Glutamate Receptor Antibodies

Includes

  • N-methyl-D-Aspartate Receptor Ab, Serum

Performing Laboratory

ARUP


Specimen Requirements

Volume Type Container Collect Temperature Transport Temperature Special Instructions
1 mLSerumSST (Gold) RefrigeratedSeparate serum from cells within 2 hours of collection.

Minimum Specimen Requirements

Volume Type Container Collect Temperature Transport Temperature Special Instructions
0.15 mL     

Stability

Environmental Condition Description
AmbientAfter separation from cells: 48 hours
FrozenAfter separation from cells: 1 year
RefrigeratedAfter separation from cells: 2 weeks

Days Performed

Sun - Sat

Turnaround Time

2 - 4 days

Methodology

Name Description
Semi-Quantitative Cell-Based Indirect Fluorescent Antibody 

Reference Range

N-methyl-D-Aspartate Receptor Antibody, IgG
Sex Age From Age To Type Range Range Unit
       < 1:10 

Special Info

If NMDA antibody IgG is positive, then an NMDA antibody IgG titer will be performed at an additional cost. Contaminated, hemolyzed, or severely lipemic specimens will be rejected. This test is New York DOH approved.

Clinical Info

NMDA receptor 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. In addition, positive results have been reported in patients with nonautoimmune phenotypes. A negative test result does not rule out a diagnosis of autoimmune limbic encephalitis. Results should be interpreted in correlation with the patients clinical history and other laboratory findings. Serum testing should be paired with CSF testing for improved diagnostic sensitivity.