Test Code AN2TC Antineuronal Nuclear Antibody Type 2 (ANNA-2) Titer, Spinal Fluid
Ordering Guidance
For investigating a smoker presenting with 1 or more elements of encephalomyeloradiculoneuropathy, order PAVAL / Paraneoplastic Autoantibody Evaluation, Serum.
Serum is preferred. Spinal fluid testing is particularly useful when interfering antibodies are present in the serum.
Specimen Required
Only orderable as a reflex. For more information see:
-DMC2 / Dementia, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
-ENC2 / Encephalopathy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
-EPC2 / Epilepsy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
-MDC2 / Movement Disorder, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
-MAC1 / Myelopathy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
Container/Tube: Sterile vial
Specimen Volume: 2 mL
Secondary ID
43441Useful For
Investigating middle-aged or older patients who present with unexplainable signs of midbrain/cerebellar/brain stem disorder and/or myelopathy, especially women with a previous history of breast cancer, and both sexes if there is a history of tobacco abuse or passive exposure
Reporting an end titer result from cerebrospinal fluid specimens
Testing Algorithm
If the indirect immunofluorescence pattern suggests antineuronal nuclear antibody type 2 (ANNA-2), then this test will be performed at an additional charge.
Method Name
Only orderable as a reflex. For more information see:
-DMC2 / Dementia, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
-ENC2 / Encephalopathy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
-EPC2 / Epilepsy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
-MDC2 / Movement Disorder, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
-MAC1 / Myelopathy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
Indirect Immunofluorescence Assay (IFA)
Specimen Type
CSFSpecimen Minimum Volume
1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
CSF | Refrigerated (preferred) | 28 days | |
Frozen | 28 days | ||
Ambient | 72 hours |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Gross icterus | Reject |
Reference Values
Only orderable as a reflex. For more information see:
-DMC2 / Dementia, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
-ENC2 / Encephalopathy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
-EPC2 / Epilepsy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
-MDC2 / Movement Disorder, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
-MAC1 / Myelopathy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
<1:2
Neuron-restricted patterns of IgG staining that do not fulfill criteria for antineuronal nuclear antibody type 2 may be reported as "unclassified antineuronal IgG." Complex patterns that include nonneuronal elements may be reported as "uninterpretable."
Interpretation
Detection of antineuronal nuclear autoantibodies type 2 (ANNA-2) in serum or spinal fluid of patients with a clinically unexplainable neurologic disorder:
-Identifies the neurologic problem as autoimmune and almost certainly paraneoplastic
-Prompts a search for underlying malignancy (breast, lung, or gynecologic)
-Leads to early treatment of cancer and consideration of immunosuppressant therapy
Method Description
The patient's sample is tested by a standardized immunofluorescence assay that uses a composite frozen section of mouse cerebellum, kidney, and gut tissues. After incubation with sample and washing, fluorescein-conjugated goat-antihuman IgG is applied. Neuron-specific autoantibodies are identified by their characteristic fluorescence staining patterns. Samples that are scored positive for any neuronal nuclear or cytoplasmic autoantibody are titrated to an endpoint. Interference by coexisting non-neuron-specific autoantibodies can usually be eliminated by serologic absorption.(Honorat JA, Komorowski L, Josephs KA, et al: IgLON5 antibody: neurological accompaniments and outcomes in 20 patients. Neurol Neuroimmunol Neuroinflamm 2017 Jul 18;4(5):e385. doi: 10.1212/NXI.0000000000000385)
If antineuronal nuclear autoantibody type 1 (ANNA-1), antinuclear antibody, or antimitochondrial antibody titers equal or exceed ANNA-2, Western blot analysis is required to establish ANNA-2 specificity with certainty.
Day(s) Performed
Monday through Sunday
Report Available
5 to 8 daysSpecimen Retention Time
28 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterCPT Code Information
86256
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
AN2TC | ANNA-2 Titer, CSF | 94357-1 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
43441 | ANNA-2 Titer, CSF | 94357-1 |