Test Details
Methodology
Immunofluorescence, Immunoblot
Result Turnaround Time
4 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Use
NMDAR1 is a glutamate receptor and ion channel found in neurons. This receptor is thought to be very important for controlling synaptic plasticity and mediating learning and memory functions. Antibodies against NMDAR1 generate both neurologic and psychiatric symptoms. Common symptoms include personality change, psychosis, abnormal movements, seizures and autonomic dysfunction. 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.
Special Instructions
If reflex test is performed, additional charges/CPT code(s) may apply.
Limitations
This test was developed and its performance characteristics determined by Labcorp in accordance with CLIA requirements. This test has not been cleared or approved by the Food and Drug Administration.
Custom Additional Information
Anti-NMDAR1 encephalitis represents one of the most frequent causes of autoimmune encephalitis. This type of encephalitis may also be associated with post-COVID-19 related neurological symptoms.
Specimen Requirements
Specimen
Cerebrospinal fluid (CSF)
Volume
2 mL
Minimum Volume
1 mL
Container
Sterile plastic tube
Stability Requirements
Temperature | Period |
|---|---|
Room temperature | 14 days |
Refrigerated | 14 days |
Frozen | 14 days |
Freeze/thaw cycles | Stable x3 |
Storage Instructions
Room temperature
Causes for Rejection
Gross hemolysis; grossly lipemic; gross icterus
References
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 505720 | Anti-NMDAR, Spinal Fluid | 82988-7 | 505599 | NMDAR Antibody, Cell-based IFA | 82988-7 | |
| Order Code | 505720 | |||||
| Order Code Name | Anti-NMDAR, Spinal Fluid | |||||
| Order Loinc | 82988-7 | |||||
| Result Code | 505599 | |||||
| Result Code Name | NMDAR Antibody, Cell-based IFA | |||||
| UofM | ||||||
| Result LOINC | 82988-7 |
| Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
|---|---|---|---|---|---|---|
| Reflex 1 | 505606 | Anti-NMDAR Antibody Titer | 505606 | Anti-NMDAR Antibody Titer | 90840-0 | |
| Reflex 1 | ||||||
| Order Code | 505606 | |||||
| Order Name | Anti-NMDAR Antibody Titer | |||||
| Result Code | 505606 | |||||
| Result Name | Anti-NMDAR Antibody Titer | |||||
| UofM | ||||||
| Result LOINC | 90840-0 | |||||