Adaptor Protein 3 Beta2 (AP3B2) Antibody, Tissue Immunofluorescence Titer, Spinal Fluid
Use
AP3B2 (adaptor protein 3 beta2)-IgG is a marker of an autoimmune disorder characterized by gait instability as the predominant neurologic presentation. Patients often exhibit cerebellar, dorsal column, or sensory neuronal dysfunction. Clinical improvement has been reported following treatment. AP3B2 autoimmunity, although rare, accompanies ataxia (sensory or cerebellar) and can be potentially treatable.
Special Instructions
Only orderable as part of a profile. Associated profiles include MAC1 (Myelopathy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid) and MDC2 (Movement Disorder, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid). An additional charge applies if the indirect immunofluorescence pattern suggests AP3B2, necessitating further testing with AP3B2 antibody cell-binding assay (CBA).
Limitations
A negative result does not exclude the presence of neurological autoimmunity or cancer. Interference may occur due to coexisting non-neuron-specific autoantibodies, though these can typically be eliminated by serologic absorption. Interpretation must consider the full clinical context to avoid diagnostic confusion due to improper specimen handling or other interfering substances.
New York Approved
Methodology
Immunoassay (Indirect Immunofluorescence Assay (IFA))
Biomarkers
LOINC Codes
- 101908-2
- 101908-2
Result Turnaround Time
5-10 days
Related Documents
For more information, please review the documents below
Specimen
Cerebrospinal Fluid
Volume
1.5 mL
Minimum Volume
Not provided
Container
Sterile vial
Collection Instructions
Preferred collection is using vial number 1, but any vial is acceptable.
Causes for Rejection
Gross hemolysis, Gross lipemia, Gross icterus
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 28 days |
| Frozen | 28 days |