Ordering Recommendation
Aids in the differential evaluation of encephalitis of unknown origin with subacute onset of seizures, confusion, memory loss, and/or behavioral change. For adults and patients with suspicion of cancer, additional evaluation of paraneoplastic autoantibodies is recommended; refer to Paraneoplastic Reflexive Panel (3002929).
Mnemonic
Methodology
Semiquantitative Cell-Based Indirect Fluorescent Antibody/Quantitative Radioimmunoassay/Semiquantitative Enzyme-Linked Immunosorbent Assay
Performed
Tue
Reported
3-10 days
New York DOH Approval Status
Specimen Required
Serum Separator Tube (SST).
Separate from cells ASAP or within 2 hours of collection. Transfer three (3) 1 mL serum aliquots to ARUP standard transport tubes. (Min: 1.5 mL)
Frozen.
Contaminated specimens.
After separation from cells: Ambient: 24 hours; Refrigerated: 1 week; Frozen: 1 month (Three freeze/thaw cycles are acceptable)
Reference Interval
Test Number |
Components |
Reference Interval |
---|---|---|
Glutamic Acid Decarboxylase Antibody | 0.0-5.0 IU/mL | |
N-methyl-D-Aspartate Receptor Ab, Serum | Less than 1:10 | |
Voltage-Gated Potassium Channel Ab, Ser | 31 pmol/L or less | |
CASPR2 Ab IgG Screen by IFA, Serum | Less than 1:10 | |
LGI1 Ab IgG Screen by IFA, Serum | Less than 1:10 | |
Neuromyelitis Optica/AQP4-IgG, Serum | Less than 1:10 | |
AMPA Receptor Ab IgG Screen, Serum | Less than 1:10 | |
GABA-B Receptor Ab IgG Screen, Serum | Less than 1:10 | |
MOG Antibody IgG Screen, Serum | Less than 1:10 | |
DPPX Ab IgG CBA IFA Screen, Serum | Less than 1:10 | |
GABA-AR Ab IgG CBA-IFA Screen, Serum | Less than 1:10 | |
IgLON5 Ab IgG CBA-IFA Screen, Serum | Less than 1:10 | |
mGluR1 Ab IgG CBA-IFA Screen, Serum | Less than 1:10 |
Interpretive Data
Refer to report.
Component |
Interpretive Data (pmol/L) |
---|---|
Voltage-Gated Potassium Channel Ab, Ser | 31 or less: Negative 32-87: Indeterminate 88 or greater: Positive |
Laboratory Developed Test (LDT)
Note
If N-methyl-D-Aspartate Receptor antibody is positive, then a titer will be added. Additional charges apply.
If Aquaporin-4 Receptor antibody IgG is positive, then a titer will be added. Additional charges apply.
If LGI1 antibody IgG is positive, then LGI1 antibody IgG titer will be added. Additional charges apply.
If CASPR2 antibody IgG is positive, then CASPR2 antibody IgG titer will be added. Additional charges apply.
If AMPAR antibody IgG is positive, then a titer will be added. Additional charges apply.
If GABABR antibody IgG is positive, then a titer will be added. Additional charges apply.
If MOG antibody IgG is positive, then a titer will be added. Additional charges apply.
If DPPX antibody IgG is positive, then a titer will be added. Additional charges apply.
If GABAAR antibody IgG is positive, then a titer will be added. Additional charges apply.
If IgLON5 antibody IgG is positive, then a titer will be added. Additional charges apply.
If mGluR1 antibody IgG is positive, then a titer will be added. Additional charge apply.
Hotline History
Hotline History
CPT Codes
83519; 86052; 86341; 86362; 86255 x9; if reflexed, add 86256 per titer.
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
2001772 | Glutamic Acid Decarboxylase Antibody | 56540-8 |
2004222 | N-methyl-D-Aspartate Receptor Ab, Serum | 80221-5 |
2004890 | Voltage-Gated Potassium Channel Ab, Ser | 41871-5 |
2009453 | CASPR2 Ab IgG Screen by IFA, Serum | 82979-6 |
2009457 | LGI1 Ab IgG Screen by IFA, Serum | 82978-8 |
2013322 | Neuromyelitis Optica/AQP4-IgG, Serum | 63439-4 |
3001261 | AMPA Receptor Ab IgG Screen, Serum | 82733-7 |
3001271 | GABA-B Receptor Ab IgG Screen, Serum | 93428-1 |
3001278 | MOG Antibody IgG Screen, Serum | 91545-4 |
3004361 | DPPX Ab IgG CBA IFA Screen, Serum | 94676-4 |
3006009 | GABA-AR Ab IgG CBA-IFA Screen, Serum | |
3006019 | IgLON5 Ab IgG CBA-IFA Screen, Serum | 96478-3 |
3006045 | mGluR1 Ab IgG CBA-IFA Screen, Serum | 93498-4 |
Aliases
- AMPA
- AQP4
- CASPR2
- DPPX
- encephalitis
- encephalopathy
- GABA-A
- GABA-B
- GAD
- GAD 65
- GAD65
- IgLON5
- LGI1
- mGluR1
- MOG
- NMDA
- VGKC