Test Catalog

Test Id : APHTC

Not Orderable

Amphiphysin Antibody Titer Assay, Spinal Fluid

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Overview

Test Catalog

Useful For
Suggests clinical disorders or settings where the test may be helpful

Evaluating patients with recent onset of a subacute neurological disorder for which a paraneoplastic basis might be suspected, particularly if the patient has a previous history, risk factors, or family history of cancer, especially lung or breast cancer

 

Reporting an end titer result from cerebrospinal fluid specimens

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

If the indirect immunofluorescence pattern suggests amphiphysin antibody, 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

-SPPC / Stiff-Person Spectrum Disorders Evaluation, including Progressive Encephalomyelitis with Rigidity and Myoclonus, 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.

Yes

Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Amphiphysin Ab Titer, CSF

Aliases
Lists additional common names for a test, as an aid in searching

Amphiphysin Antibody

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

If the indirect immunofluorescence pattern suggests amphiphysin antibody, 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. Spinal fluid testing is particularly useful if interfering antibodies are present in the serum.

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

-SPPC / Stiff-Person Spectrum Disorders Evaluation, including Progressive Encephalomyelitis with Rigidity and Myoclonus, Spinal Fluid

 

Container/Tube: Sterile vial

Specimen Volume: 4 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.

2 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
Frozen 28 days
Ambient 72 hours

Useful For
Suggests clinical disorders or settings where the test may be helpful

Evaluating patients with recent onset of a subacute neurological disorder for which a paraneoplastic basis might be suspected, particularly if the patient has a previous history, risk factors, or family history of cancer, especially lung or breast cancer

 

Reporting an end titer result from cerebrospinal fluid specimens

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

If the indirect immunofluorescence pattern suggests amphiphysin antibody, 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

Antineuronal autoantibodies specific for amphiphysin (a 128-kDa synaptic vesicle-associated protein) are found in a paraneoplastic context. These IgG antibodies were initially described as a serological marker of paraneoplastic stiff-man syndrome associated with breast carcinoma. They are now more aptly recognized as a marker of autoimmune encephalomyeloneuritis, sensory neuronopathy, and assorted neuromyopathic disorders associated with small-cell lung carcinoma or breast carcinoma.

 

Only 1 of 30 patients identified as seropositive for amphiphysin antibodies in the Mayo Clinic Neuroimmunology Laboratory exhibited any stiff-person phenomena (n=63: 39% women, 12% men). Only 10% of women (some with lung carcinoma) and 4% of men fulfilled diagnostic criteria for stiff-man syndrome. Overall, cancer was detected in 79.4% of seropositive patients (at last follow-up). Lung carcinoma (small cell) accounted for 61% of cancers and 35% had breast carcinoma (42% for women).

 

Amphiphysin seropositivity implicates antineuronal autoimmunity as the basis for a variety of neurological presentations and focuses the patient's subsequent investigation to a search for breast carcinoma or small-cell lung carcinoma.

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

-SPPC / Stiff-Person Spectrum Disorders Evaluation, including Progressive Encephalomyelitis with Rigidity and Myoclonus, Spinal Fluid

 

<1:2

Neuron-restricted patterns of IgG staining that do not fulfill criteria for amphiphysin antibody may be reported as "unclassified antineuronal IgG." Complex patterns that include nonneuronal elements may be reported as "uninterpretable."

Interpretation
Provides information to assist in interpretation of the test results

Positive results are consistent with neurologic autoimmunity; usually related to breast carcinoma or small-cell lung carcinoma.

Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

Nonorgan-specific autoantibodies in high titer preclude identification of amphiphysin IgG by indirect immunofluorescence; Western blot assay should be done in those cases.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Folli F, Solimena M, Cofiell R, et al: Autoantibodies to a 128-kd synaptic protein in three women with the stiff-man syndrome and breast cancer. N Engl J Med. 1993 Feb 25;328(8):546-551

2. Pittock SJ, Lucchinetti CF, Parisi JE, et al: Amphiphysin autoimmunity: paraneoplastic accompaniments. Ann Neurol. 2005 Jul;58(1):96-107

3. McKeon A, Pittock SJ: Paraneoplastic encephalomyelopathies: pathology and mechanisms. Acta Neuropathol. 2011 Oct;122(4):381-400

4. 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

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

No

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.

6 to 8 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

28 days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test

Rochester

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.
  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • 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.

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
APHTC Amphiphysin Ab Titer, CSF 94354-8
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.
618164 Amphiphysin Ab Titer, CSF 94354-8

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports