Ordering Recommendation

Aids in the diagnosis of cerebellar ataxia and limbic encephalitis. May be used to monitor treatment response in individuals who are antibody positive. The presence of mGluR1 antibodies may be associated with subacute cerebellar ataxia, dysgeusia, dysarthria, head titubation, and cognitive impairment. mGluR1 encephalitis may be paraneoplastic; hematologic malignancies are reported in a subset of patients.

New York DOH Approval Status

This test is New York state approved.

Specimen Required

Patient Preparation
Collect

Serum separator tube.

Specimen Preparation

Separate serum from cells within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.2 mL)

Storage/Transport Temperature

Refrigerated.

Unacceptable Conditions

CSF or plasma. Contaminated, grossly hemolyzed, icteric, or lipemic specimens.

Remarks
Stability

After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 month (Three freeze/thaw cycles are acceptable)

Methodology

Semiquantitative Cell-Based Indirect Fluorescent Antibody

Performed

Wed

Reported

Within 8 days

Reference Interval

Less than 1:10

Interpretive Data

Metabotropic glutamate receptor 1 (mGluR1) antibody is found in a subset of patients with autoimmune cerebellar ataxia or autoimmune encephalitis and may occur with or without associated tumor. A negative test result does not rule out a diagnosis of autoimmune cerebellar ataxia or limbic encephalitis. Interpretation of any antineural antibody test requires clinical correlation.
  
This indirect fluorescent antibody assay utilizes mGluR1 transfected cell lines for detection and semiquantification of mGluR1 IgG antibody.

Compliance Category

Laboratory Developed Test (LDT)

Note

If mGluR1 antibody IgG is positive, then mGluR1 antibody IgG titer will be added. Additional charges apply.

Hotline History

N/A

CPT Codes

86255; if reflexed, add 86256

Components

Component Test Code* Component Chart Name LOINC
3006045 mGluR1 Ab IgG CBA-IFA Screen, Serum 93498-4
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.

Aliases

  • cerebellar ataxia
  • dementia
  • encephalitis
  • encephalopathy
  • epilepsy
  • Limbic encephalitis
  • movement disorder
  • myelopathy
  • pediatric CNS disorder
Metabotropic Glutamate Receptor 1 (mGluR1) Antibody, IgG by CBA-IFA With Reflex to Titer, Serum