Alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid Receptor (AMPAR) Antibody, IgG by CBA-IFA With Reflex to Titer, CSF
Ordering Recommendation
Aid in diagnosis of limbic encephalitis. May be used in monitoring treatment response in individuals who are antibody positive. The presence of AMPA receptor antibodies may be associated with psychosis, with or without seizures; AMPA encephalitis may be paraneoplastic but tumor type is variable (thymic, lung, and breast cancer).
New York DOH Approval Status
Specimen Required
CSF.
Transfer 0.5 mL CSF to an ARUP standard transport tube. (Min: 0.15 mL)
Refrigerated.
Hemolyzed, contaminated, or severely lipemic specimens.
Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 month
Methodology
Semi-Quantitative Cell-Based Indirect Fluorescent Antibody
Performed
Wed
Reported
1-8 days
Reference Interval
Less than 1:1
Interpretive Data
Alpha-amino-3-hydroxy-5-methyl-4-isoxazoleproprionic acid receptor (AMPAR) 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. A negative test result does not rule out a diagnosis of autoimmune encephalitis. Results should be interpreted in correlation with the patients clinical history and other laboratory findings.
This indirect fluorescent antibody assay utilizes AMPAR transfected cell lines for detection and semiquantification of AMPAR IgG antibody.
Laboratory Developed Test (LDT)
Note
If Alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid (AMPA) Receptor Antibody, IgG by IFA with Reflex to Titer, CSF IgG is positive, then an Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid (AMPA) Receptor Antibody Titer, IgG, CSF is reported. Additional charges apply.
Hotline History
Hotline History
CPT Codes
86255; if reflexed, add 86256
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
3001258 | AMPA Receptor Ab IgG CBA-IFA Screen, CSF | 82732-9 |
Aliases
- AMPA
- AMPA Receptor Ab
- AMPA Reflex
- AMPA Titer