Test Id : AGNTC
Anti-Glial/Neuronal Nuclear Antibody-Type 1 (AGNA-1) Titer, Spinal Fluid
Useful For
Suggests clinical disorders or settings where the test may be helpful
Reporting an end titer result from cerebrospinal fluid (CSF) specimens
Serological evaluation using CSF specimens from patients who present with a subacute neurological disorder of undetermined etiology, especially those with risk factors for primary lung carcinoma
Directing a focused search for cancer
Investigating neurological symptoms that appear during, or after, cancer therapy and are not explainable by metastasis
Differentiating autoimmune neuropathies from neurotoxic effects of chemotherapy
Monitoring the immune response of seropositive patients during cancer therapy
Detecting early evidence of cancer recurrence in previously seropositive patients
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
If the indirect immunofluorescence pattern suggests anti-glial/neuronal nuclear antibody-type 1 (AGNA-1), then this test will be performed at an additional charge.
Method Name
A short description of the method used to perform the test
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)
NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test
Aliases
Lists additional common names for a test, as an aid in searching
AGNA
ANNA-4
Anti-Glial Nuclear Antibody
SOX
SOX-1
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
If the indirect immunofluorescence pattern suggests anti-glial/neuronal nuclear antibody-type 1 (AGNA-1), then this test will be performed at an additional charge.
Specimen Type
Describes the specimen type validated for testing
CSF
Ordering Guidance
Serum is preferred; see AGN1S / Anti-Glial/Neuronal Nuclear Antibody-Type 1, Serum.
Spinal fluid is particularly useful if interfering antibodies are present.
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
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
Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the testing laboratory. The minimum volume is sufficient for one attempt at testing.
1 mL
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
| Gross hemolysis | Reject |
| Gross lipemia | Reject |
| Gross icterus | Reject |
Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| CSF | Refrigerated (preferred) | 28 days | |
| Ambient | 72 hours | ||
| Frozen | 28 days |
Useful For
Suggests clinical disorders or settings where the test may be helpful
Reporting an end titer result from cerebrospinal fluid (CSF) specimens
Serological evaluation using CSF specimens from patients who present with a subacute neurological disorder of undetermined etiology, especially those with risk factors for primary lung carcinoma
Directing a focused search for cancer
Investigating neurological symptoms that appear during, or after, cancer therapy and are not explainable by metastasis
Differentiating autoimmune neuropathies from neurotoxic effects of chemotherapy
Monitoring the immune response of seropositive patients during cancer therapy
Detecting early evidence of cancer recurrence in previously seropositive patients
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
If the indirect immunofluorescence pattern suggests anti-glial/neuronal nuclear antibody-type 1 (AGNA-1), then this test will be performed at an additional charge.
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Anti-glial/neuronal nuclear autoantibody-type 1 (AGNA-1) is recognized clinically as a marker of a patient's immune response to a lung cancer that is usually limited in metastasis but manifests as an autoimmune neurological disorder.
AGNA-1 is an IgG marker of an immune response to cancer (usually a small-cell lung carcinoma: SCLC) in patients presenting with a subacute, generally multifocal, paraneoplastic neurological disorder.(1-3) It binds to the nucleus, but not cytoplasm, of SCLC cell lines and, in the adult central nervous system, to nuclei in subsets of astrocytes and neurons, as well as ependyma. Its previous name was antineuronal nuclear antibody (ANNA)-4.(2) The most common neurological presentations of patients who are positive for AGNA-1 are Lambert-Eaton myasthenic syndrome, sensorimotor or autonomic neuropathy, limbic encephalopathy, and ataxias.
To date, all 45 seropositive patients identified in the Mayo Clinic Neuroimmunology Laboratory have been smokers. SCLC was confirmed in more than 80% of cases. In 59% of patients, one or more identifiable coexisting paraneoplastic autoantibodies support the prediction of SCLC: P/Q-type Ca(++) channel antibody (41%) greater than collapsin response-mediator protein-5 (CRMP-5)-IgG equal to ANNA-1 greater than other antibodies.
Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
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 anti-glial/neuronal nuclear antibody-type 1 may be reported as "unclassified anti-neuronal IgG." Complex patterns that include nonneuronal elements may be reported as "uninterpretable."
Interpretation
Provides information to assist in interpretation of the test results
A positive result confirms that the patient's subacute neurological disorder has an autoimmune basis and predicts with greater than 80% certainty that the patient has a lung carcinoma (usually small-cell lung carcinoma: SCLC), either new or recurrent, and confined to the chest. Fifteen percent of seropositive patients who are eventually proven to have SCLC additionally have an unrelated, often more obvious, cancer, either coexisting or by past history.
Anti-glial/neuronal nuclear autoantibody-type 1 (AGNA-1) has not been encountered in healthy subjects (n=170). Its onconeural antigen is the nuclear transcription factor Sox1.(2) IgG of this specifically has been reported detectable in 30% to 40% of patients with SCLC who lack neurological complications.(4)
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Anti-glial/neuronal nuclear autoantibody-type 1 (AGNA-1) is difficult to detect by immunofluorescence when it coexists with other neuronal nuclear autoantibodies, such as antineuronal nuclear antibody (ANNA)-1 or ANNA-2, unless the titer of AGNA-1 exceeds that of the coexisting autoantibodies. It has not been detected by Western blot.(1)
Clinical Reference
Recommendations for in-depth reading of a clinical nature
1. Graus F, Vincent A, Pozo-Rosich P, et al: Anti-glial nuclear antibody: marker of lung cancer-related paraneoplastic neurological syndromes. J Neuroimmunol. 2005 Aug;165(1-2):166-171
2. Lachance D, Kryzer TJ, Pittock SJ, et al: Anti-neuronal nuclear antibody type 4 (ANNA-4), a novel paraneoplastic marker of small-cell lung carcinoma (SCLC). Neurology. 2006;66 (Suppl 2):A340
3. Sabater L, Saiz A, Titulaer MG, et al: Sox1 antibodies are markers of paraneoplastic Lambert-Eaton myasthenic syndrome. Neurology. 2008 Mar 18;70(12):924-928
4. Gure AO, Stockert E, Scanlan MJ, et al: Serological identification of embryonic neural proteins as highly immunogenic tumor antigens in small cell lung cancer. Proc Natl Acad Sci USA. 2000 Apr 11;97(8):4198-4203
5. McKeon A, Pittock SJ: Paraneoplastic encephalomyelopathies: pathology and mechanisms. Acta Neuropathol. 2011 Oct;122(4):381-400
6. Horta ES, Lennon VA, Lachance DH, et al: Neural autoantibody clusters aid diagnosis of cancer. Clin Cancer Res. 2014 Jul 15;20(14):3862-3869
7. Pittock SJ, Kryzer TJ, Lennon VA: Paraneoplastic antibodies coexist and predict cancer, not neurological syndrome. Ann Neurol. 2004 Nov;56(5):715-719
Method Description
Describes how the test is performed and provides a method-specific reference
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)
PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information
Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.
Monday through Sunday
Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.
Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location
Indicates the location of the laboratory that performs the test
Fees :
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.
- Authorized users can sign in to Test Prices for detailed fee information.
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- Prospective clients should contact their account representative. For assistance, contact Customer Service.
Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.
CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
CPT codes are provided by the performing laboratory.
CPT codes are provided by the performing laboratory.
86256
LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.
| Test Id | Test Order Name | Order LOINC Value |
|---|---|---|
| AGNTC | AGNA-1 Titer, CSF | 93455-5 |
| Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
|---|---|---|
| 43443 | AGNA-1 Titer, CSF | 94355-5 |