N-methyl-D-Aspartate Receptor Antibody, IgG, Serum with Reflex to Titer
Ordering Recommendation
Confirm diagnosis of NMDAR antibody encephalitis.
Submit With Order
Semi-Quantitative Indirect Fluorescent Antibody
Tue, Fri
1-5 days
New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
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: 0.15 mL)  
Storage/Transport Temperature
Unacceptable Conditions
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
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.
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
Component Test Code*Component Chart Name
2004222N-methyl-D-Aspartate Receptor Ab, Serum
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Cross References
  • Anti-NMDA
  • Glutamate Receptor Antibodies
  • N-Methyl D-Aspartate Ab
  • NMDA R
  • NMDA Receptor Ab
  • NMDA Reflex
  • NMDA Titer