Ordering Recommendation

Aids in the diagnosis of autoimmune cerebellar ataxia, encephalitis, neuropathy, and myelopathy. May be used to monitor treatment response in individuals who are antibody positive. The presence of ITPR1 antibodies may be associated with cerebellar ataxia, encephalitis with seizures, peripheral neuropathy, and myelopathy. ITPR1 antibody disease may be paraneoplastic, but tumor type is variable (eg, breast, lung, and renal cancers).

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

1-8 days

Reference Interval

Less than 1:10

Interpretive Data

Inositol 1, 4, 5-trisphosphate receptor type 1 (ITPR1) antibody is found in a subset of patients with autoimmune cerebellar ataxia, encephalitis, neuropathy, or myelopathy and may occur with or without associated tumor. A negative test result does not rule out a diagnosis of autoimmune cerebellar ataxia or related autoimmune neurologic disorders. Interpretation of any antineural antibody test requires clinical correlation.
  
This indirect fluorescent antibody assay utilizes ITPR1 transfected cell lines for detection and semiquantification of ITPR1 IgG antibody.

Compliance Category

Laboratory Developed Test (LDT)

Note

If ITPR1 antibody IgG is positive, then ITPR1 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
3006032 ITPR1 Ab IgG CBA-IFA Screen, Serum 96466-8
* 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
  • encephalitis
  • ITPR 1
  • movement disorder
  • myelopathy
  • neuropathy
Inositol 1,4,5-Trisphosphate Receptor Type 1 (ITPR1) Antibody, IgG by CBA-IFA With Reflex to Titer, Serum