ARUP's Laboratory Test Directory

N-methyl-D-Aspartate Receptor Antibody, IgG, Serum with Reflex to Titer : 2004221
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Additional Technical Information
  


Mnemonic: NMDA IGG

Methodology: Semi-Quantitative Indirect Fluorescent Antibody
Performed: Tue
Reported: 1-9 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: 0.2 mL)

Storage/Transport Temperature: Refrigerated.

Unacceptable Conditions: CSF or plasma. Contaminated, hemolyzed, or severely lipemic specimens.

Stability (collection to initiation of testing): After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)
Reference Interval:
Effective May 21, 2012
< 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.
Note: If NMDA antibody IgG is positive, then an NMDA antibody IgG titer is reported. Additional charges apply.
CPT Code(s): 86255; if reflexed, add 86256
Cross References: Glutamate Receptor Antibodies (N-methyl-D-Aspartate Receptor Antibody, IgG, Serum), NMDA R (N-methyl-D-Aspartate Receptor Antibody, IgG, Serum)