Purkinje Cell Cytoplasmic Antibody Type 2 (PCA-2) Titer, Spinal Fluid
Use
The PCA-2 Titer test is useful for evaluating patients presenting with subacute neurological disorders of undetermined etiology who have risk factors for lung cancer. It aids in the diagnosis by detecting Purkinje cell cytoplasmic antibody type 2, an autoantibody associated with immune responses to small-cell lung carcinoma (SCLC). Positive results may direct a thorough search for lung cancer, especially small-cell carcinoma, as these antibodies are found in less than 2% of uncomplicated SCLC cases.
Special Instructions
This test is only orderable as a reflex if the indirect immunofluorescence pattern suggests Purkinje cell cytoplasmic antibody type 2 (PCA-2). It may be particularly useful when interfering antibodies are present in the serum. This test carries an additional charge if reflexively added.
Limitations
The test's performance may be complicated by the presence of interfering autoantibodies, which can preclude interpretation of the immunofluorescence pattern. In such cases, a Western blot with native neuronal proteins may be required. The effectiveness of the test may also be reduced by complex patterns including non-neuronal elements, which could be reported as 'uninterpretable'.
New York Approved
Methodology
Immunoassay (IFA)
Biomarkers
LOINC Codes
- 94364-7
- 94364-7
Result Turnaround Time
6-8 days
Related Documents
For more information, please review the documents below
Specimen
Cerebrospinal Fluid
Volume
4 mL
Minimum Volume
2 mL
Container
Sterile vial
Patient Preparation
Serum is preferred; spinal fluid testing is particularly useful when interfering antibodies are present in the serum.
Causes for Rejection
Gross hemolysis, Gross lipemia, Gross icterus
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 28 days |
| Frozen | 28 days |