Ordering Recommendation: Confirm diagnosis of anti-NMDAR encephalitis. May be used in monitoring treatment response in individuals who are antibody positive.
Test Algorithm: If the NMDA antibody IgG is positive, the NMDA antibody titer will be performed at additional charge.
Ordering Note: This is a non-orderable battery included in package NMDA Receptor IgG Antibody with Reflex, Serum (Sendout) [RNMDAG].
Code | Name |
---|---|
RNMDAR | NMDA Receptor IgG Antibody, Serum |
Semi-Quantitative Cell-Based Indirect Fluorescent Antibody
Reference Range: | < 1:10 |
Interpretive Data: 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.
This indirect fluorescent antibody assay utilizes full-length GluN1 transfected cell lines for the detection and semiquantification of NMDA receptor IgG antibody.
6 mL blood in RED TOP tube or GOLD SST
Centrifuge sample and transfer 1 mL serum each into two separate plastic vials within 2 hours of collection. If sample volume is low, prioritize the sendout test (RNMDA).
Sendouts:
Stability: Refrigerated (preferred): 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles); Ambient: 48 hours.
Unacceptable Conditions: CSF or plasma. Contaminated, hemolyzed, or severely lipemic specimens.
Sendout |
ARUP Laboratories, Inc.
800-522-2787 500 Chipeta Way |
---|