Antineuronal Nuclear Antibody Type 3 (ANNA-3) Titer, Spinal Fluid
Use
The test is useful for evaluating patients with a subacute neurological disorder of unknown cause, especially those at risk for primary lung carcinoma. It helps detect the presence of antineuronal nuclear antibody type 3 (ANNA-3) in cerebrospinal fluid, which is indicative of an immune response, typically associated with small-cell lung carcinoma (SCLC). The presence of ANNA-3 suggests the neurological disorder may have an autoimmune basis, potentially predicting the existence of an underlying malignancy, such as SCLC.
Special Instructions
This assay is performed as a reflex test only when the indirect immunofluorescence patterns suggest ANNA-3. It cannot be ordered independently. The test requires a cerebrospinal fluid specimen and may incur additional charges based on testing algorithms.
Limitations
This test may not detect ANNA-3 if coexisting neuronal nuclear antibodies are more prevalent unless identifiable by a higher titer or demonstrable through Western blot. The assay is specific to detecting immunological markers relevant to neurological disorders associated with lung carcinoma, and results should be interpreted in the context of other clinical findings.
New York Approved
Methodology
Immunoassay (Indirect Immunofluorescence Assay (IFA))
Biomarkers
LOINC Codes
- 94358-9
- 94358-9
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
Causes for Rejection
Gross hemolysis, gross lipemia, gross icterus
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 28 days |
| Frozen | 28 days |