Test Code LAB2004221 NMDA RECEPTOR ANTIBODY, IgG, SERUM WITH REFLEX TO TITER
Performing Laboratory
St. Louis Children's Hospital Sendout to ARUP Laboratories
Specimen Requirements
Specimen Type: Blood
Patient Preparation: None
Container/Tube
Preferred: Gold/Red SST Vacutainer®
Acceptable: Plain, red-top Vacutainer®
Collection Volume: 2.0 mL (minimum 0.5 mL)
Special Instructions: Send to lab promptly
Sample Rejection
Specimens that are grossly hemolyzed and/or lipemic
Mislabeled or unlabeled specimens.
Logistics
Test Availability: Daily
Cut-off time: None
Days set up by performing lab: Sunday - Saturday
Turnaround Time: 2-4 days
Reference Values
Reference Interval:
<1:10
Interpretation: 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
Critical Value: None established
Methodology
Semi-Quantitative Indirect Fluorescent Antibody
This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the U.S. Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes
Limitations
NA
Additional Information
FOR SLCH CORE LABORATORY USE ONLY
Lab Processing Instructions: Centrifuge specimen to separate within 2 hours of collection. Aliquot supernatant into a 5-mL screw-cap plastic vial for transport.
Processed Volume: 1.0 mL (minimum 0.2 mL) serum
Transport Temperature: Refrigerated
Analyte Stability:
Ambient (unprocessed):2 hours
PROCESSED:
Ambient: 48 hours
Refrigerated: 2 weeks
Frozen: 1 year
Note: Specimen must be separated from clot within 2 hours of collection.
Avoid repeated freeze/thaw cycles
Test Classification and CPT Code
86255
86256: titer (if appropriate)
LOINC
80221-5
Last Reviewed
08/2025