Test Catalog

Test Id : EPC2

Epilepsy, Autoimmune Evaluation, Spinal Fluid

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

Investigating new onset cryptogenic epilepsy with incomplete seizure control and duration of less than 2 years using spinal fluid specimens

 

Investigating new onset cryptogenic epilepsy plus 1 or more of the following accompaniments:

-Psychiatric accompaniments (psychosis, hallucinations)

-Movement disorder (myoclonus, tremor, dyskinesias)

-Headache

-Cognitive impairment/encephalopathy

-Autoimmune stigmata (personal history or family history or signs of diabetes mellitus, thyroid disorder, vitiligo, premature graying of hair, myasthenia gravis, rheumatoid arthritis, systemic lupus erythematosus, idiopathic adrenocortical insufficiency) or "multiple sclerosis"

-History of cancer

-Smoking history (20+ pack years) or other cancer risk factors

-Investigating seizures occurring within the context of a subacute multifocal neurological disorder without obvious cause, especially in a patient with past or family history of cancer

Profile Information
A profile is a group of laboratory tests that are ordered and performed together under a single Mayo Test ID. Profile information lists the test performed, inclusive of the test fee, when a profile is ordered and includes reporting names and individual availability.

Test Id Reporting Name Available Separately Always Performed
AEPCI Epilepsy, Interpretation, CSF No Yes
AMPCC AMPA-R Ab CBA, CSF No Yes
AMPHC Amphiphysin Ab, CSF No Yes
AGN1C Anti-Glial Nuclear Ab, Type 1 No Yes
ANN1C Anti-Neuronal Nuclear Ab, Type 1 No Yes
ANN2C Anti-Neuronal Nuclear Ab, Type 2 No Yes
ANN3C Anti-Neuronal Nuclear Ab, Type 3 No Yes
CS2CC CASPR2-IgG CBA, CSF No Yes
CRMC CRMP-5-IgG, CSF No Yes
DPPIC DPPX Ab IFA, CSF No Yes
GD65C GAD65 Ab Assay, CSF Yes Yes
GABCC GABA-B-R Ab CBA, CSF No Yes
GFAIC GFAP IFA, CSF No Yes
LG1CC LGI1-IgG CBA, CSF No Yes
GL1IC mGluR1 Ab IFA, CSF No Yes
NMDCC NMDA-R Ab CBA, CSF No Yes
PCTRC Purkinje Cell Cytoplasmc Ab Type Tr No Yes
PCA2C Purkinje Cell Cytoplasmic Ab Type 2 No Yes

Reflex Tests
Lists tests that may or may not be performed, at an additional charge, depending on the result and interpretation of the initial tests.

Test Id Reporting Name Available Separately Always Performed
AGNBC AGNA-1 Immunoblot, CSF No No
AMPIC AMPA-R Ab IF Titer Assay, CSF No No
AMIBC Amphiphysin Immunoblot, CSF No No
AN1BC ANNA-1 Immunoblot, CSF No No
AN2BC ANNA-2 Immunoblot, CSF No No
CRMWC CRMP-5-IgG Western Blot, CSF Yes No
DPPCC DPPX Ab CBA, CSF No No
DPPTC DPPX Ab IFA Titer, CSF No No
GABIC GABA-B-R Ab IF Titer Assay, CSF No No
GFACC GFAP CBA, CSF No No
GFATC GFAP IFA Titer, CSF No No
GL1CC mGluR1 Ab CBA, CSF No No
GL1TC mGluR1 Ab IFA Titer, CSF No No
NMDIC NMDA-R Ab IF Titer Assay, CSF No No
PC1BC PCA-1 Immunoblot, CSF No No
PCTBC PCA-Tr Immunoblot, CSF No No
PCA1C Purkinje Cell Cytoplasmic Ab Type 1 No No

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

If client requests or if indirect immunofluorescence assay (IFA) patterns suggest collapsin response-mediator protein-5-IgG (CRMP-5-IgG), then CRMP-5-IgG Western blot is performed at an additional charge.

 

If IFA patterns suggest amphiphysin antibody, then amphiphysin immunoblot is performed at an additional charge.

 

If IFA pattern suggests AGNA-1 antibody, then AGNA-1 immunoblot is performed at an additional charge.

 

If IFA pattern suggests ANNA-1 antibody, then ANNA-1 immunoblot is performed at an additional charge.

 

If IFA pattern suggests ANNA-2 antibody, then ANNA-2 immunoblot is performed at an additional charge.

 

If IFA pattern suggests PCA-1 antibody, then PCA-1 immunoblot is performed at an additional charge.

 

If IFA pattern suggests PCA-Tr antibody, then PCA-Tr immunoblot is performed at an additional charge.

 

If IFA pattern suggests AMPA-receptor antibody, and AMPA-receptor antibody cell-binding assay (CBA) is positive, then AMPA-receptor antibody IF titer assay is performed at an additional charge.

 

If IFA pattern suggests GABA-B-receptor antibody, and GABA-B-receptor antibody is positive, then GABA-B-receptor antibody IF titer assay is performed at an additional charge.

 

If IFA pattern suggests GFAP antibody, then GFAP IFA titer and GFAP CBA are performed at an additional charge.

 

If IFA pattern suggests NMDA-receptor antibody, and NMDA-receptor antibody CBA is positive, then NMDA-receptor antibody IF titer assay is performed at an additional charge.

 

If IFA patterns suggest PCA-1, then PCA1C assay is performed at an additional charge.

 

If IFA pattern suggests DPPX antibody, then DPPX antibody CBA and DPPX titer are performed at an additional charge.

 

If IFA pattern suggests mGluR1 antibody, then mGluR1 antibody CBA and mGluR1 titer are performed at an additional charge.

 

See Epilepsy Autoimmune Evaluation Algorithm, Spinal Fluid in Special Instructions.

Special Instructions
Library of PDFs including pertinent information and forms related to the test

Method Name
A short description of the method used to perform the test

AGN1C, AMPHC, AMPIC, ANN1C, ANN2C, ANN3C, CRMC, DPPIC, DPPTC, GABIC, GFAIC, GFATC, GL1IC, GL1TC, NMDIC, PCA1C, PCA2C, PCTRC: Indirect Immunofluorescence Assay (IFA)

AMPCC, CS2CC, DPPCC, GABCC, GFACC, GL1CC, LG1CC, NMDCC: Cell-Binding Assay (CBA)

CRMWC: Western Blot (WB)

AGNBC, AMIBC, AN1BC, AN2BC, PC1BC, PCTBC: Immunoblot (IB)

GD65C:  Radioimmunoassay (RIA)

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

Epilepsy-Autoimmune Evaluation, CSF

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

AMPA-R Ab CBA

Amphiphysin Ab

Anti-Glial Nuclear Ab, Type 1

Anti-Neuronal Nuclear Ab, Type 1

Anti-Neuronal Nuclear Ab, Type 2

Anti-Neuronal Nuclear Ab, Type 3

CASPR2-IgG

Contactin-Associated Protein-Like-2 (CASPR2)-IgG

CRMP-5-IgG

DPPX

Dipeptidyl aminopeptidase-like protein 6

EPIEC

GABA-B-R Ab CBA

Glutamic Acid Decarboxylase (GAD65)

LGI1-IgG

NMDA-R Ab CBA

Metabotropic glutamate receptor 1

mGluR1

Purkinje Cell Cytoplasmic Ab Type 2

Purkinje Cell Cytoplasmic Ab Type Tr

Seizures

Spells

GFAP

Leucine-Rich Glioma Inactivated Protein-1 IgG

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

If client requests or if indirect immunofluorescence assay (IFA) patterns suggest collapsin response-mediator protein-5-IgG (CRMP-5-IgG), then CRMP-5-IgG Western blot is performed at an additional charge.

 

If IFA patterns suggest amphiphysin antibody, then amphiphysin immunoblot is performed at an additional charge.

 

If IFA pattern suggests AGNA-1 antibody, then AGNA-1 immunoblot is performed at an additional charge.

 

If IFA pattern suggests ANNA-1 antibody, then ANNA-1 immunoblot is performed at an additional charge.

 

If IFA pattern suggests ANNA-2 antibody, then ANNA-2 immunoblot is performed at an additional charge.

 

If IFA pattern suggests PCA-1 antibody, then PCA-1 immunoblot is performed at an additional charge.

 

If IFA pattern suggests PCA-Tr antibody, then PCA-Tr immunoblot is performed at an additional charge.

 

If IFA pattern suggests AMPA-receptor antibody, and AMPA-receptor antibody cell-binding assay (CBA) is positive, then AMPA-receptor antibody IF titer assay is performed at an additional charge.

 

If IFA pattern suggests GABA-B-receptor antibody, and GABA-B-receptor antibody is positive, then GABA-B-receptor antibody IF titer assay is performed at an additional charge.

 

If IFA pattern suggests GFAP antibody, then GFAP IFA titer and GFAP CBA are performed at an additional charge.

 

If IFA pattern suggests NMDA-receptor antibody, and NMDA-receptor antibody CBA is positive, then NMDA-receptor antibody IF titer assay is performed at an additional charge.

 

If IFA patterns suggest PCA-1, then PCA1C assay is performed at an additional charge.

 

If IFA pattern suggests DPPX antibody, then DPPX antibody CBA and DPPX titer are performed at an additional charge.

 

If IFA pattern suggests mGluR1 antibody, then mGluR1 antibody CBA and mGluR1 titer are performed at an additional charge.

 

See Epilepsy Autoimmune Evaluation Algorithm, Spinal Fluid in Special Instructions.

Specimen Type
Describes the specimen type validated for testing

CSF

Necessary Information

Provide the following information:

-Relevant clinical information

-Ordering provider name, phone number, mailing address, and e-mail address

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Collection Container/Tube: Sterile vial

Specimen Volume: 4 mL

Special Instructions
Library of PDFs including pertinent information and forms related to the test

Forms

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

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

Investigating new onset cryptogenic epilepsy with incomplete seizure control and duration of less than 2 years using spinal fluid specimens

 

Investigating new onset cryptogenic epilepsy plus 1 or more of the following accompaniments:

-Psychiatric accompaniments (psychosis, hallucinations)

-Movement disorder (myoclonus, tremor, dyskinesias)

-Headache

-Cognitive impairment/encephalopathy

-Autoimmune stigmata (personal history or family history or signs of diabetes mellitus, thyroid disorder, vitiligo, premature graying of hair, myasthenia gravis, rheumatoid arthritis, systemic lupus erythematosus, idiopathic adrenocortical insufficiency) or "multiple sclerosis"

-History of cancer

-Smoking history (20+ pack years) or other cancer risk factors

-Investigating seizures occurring within the context of a subacute multifocal neurological disorder without obvious cause, especially in a patient with past or family history of cancer

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

If client requests or if indirect immunofluorescence assay (IFA) patterns suggest collapsin response-mediator protein-5-IgG (CRMP-5-IgG), then CRMP-5-IgG Western blot is performed at an additional charge.

 

If IFA patterns suggest amphiphysin antibody, then amphiphysin immunoblot is performed at an additional charge.

 

If IFA pattern suggests AGNA-1 antibody, then AGNA-1 immunoblot is performed at an additional charge.

 

If IFA pattern suggests ANNA-1 antibody, then ANNA-1 immunoblot is performed at an additional charge.

 

If IFA pattern suggests ANNA-2 antibody, then ANNA-2 immunoblot is performed at an additional charge.

 

If IFA pattern suggests PCA-1 antibody, then PCA-1 immunoblot is performed at an additional charge.

 

If IFA pattern suggests PCA-Tr antibody, then PCA-Tr immunoblot is performed at an additional charge.

 

If IFA pattern suggests AMPA-receptor antibody, and AMPA-receptor antibody cell-binding assay (CBA) is positive, then AMPA-receptor antibody IF titer assay is performed at an additional charge.

 

If IFA pattern suggests GABA-B-receptor antibody, and GABA-B-receptor antibody is positive, then GABA-B-receptor antibody IF titer assay is performed at an additional charge.

 

If IFA pattern suggests GFAP antibody, then GFAP IFA titer and GFAP CBA are performed at an additional charge.

 

If IFA pattern suggests NMDA-receptor antibody, and NMDA-receptor antibody CBA is positive, then NMDA-receptor antibody IF titer assay is performed at an additional charge.

 

If IFA patterns suggest PCA-1, then PCA1C assay is performed at an additional charge.

 

If IFA pattern suggests DPPX antibody, then DPPX antibody CBA and DPPX titer are performed at an additional charge.

 

If IFA pattern suggests mGluR1 antibody, then mGluR1 antibody CBA and mGluR1 titer are performed at an additional charge.

 

See Epilepsy Autoimmune Evaluation Algorithm, Spinal Fluid in Special Instructions.

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Antiepileptic drugs (AEDs) are the mainstay of treatment for epilepsy, but seizures continue in one-third of patients despite appropriate AED therapeutic trials. The etiology of epilepsy often remains unclear. Seizures are a common symptom in autoimmune neurological disorders, including limbic encephalitis and multifocal paraneoplastic disorders. Seizures may be the exclusive manifestation of an autoimmune encephalopathy without evidence of limbic encephalitis.

 

Autoimmune epilepsy is increasingly recognized in the spectrum of neurological disorders characterized by detection of neural autoantibodies in serum or spinal fluid and responsiveness to immunotherapy. The advent of more sensitive and specific serological detection methods is increasingly revealing previously underappreciated autoimmune epilepsies. Neural autoantibodies specific for intracellular and plasma membrane antigens aid the diagnosis of autoimmune epilepsy, but no single antibody is specific for this diagnosis.

 

Autoantibody specificities currently most informative for autoimmune epilepsies include leucine-rich glioma inactivated protein-1 (LGI1), glutamic acid decarboxylase-65 (GAD65), N-methyl-D-aspartate receptor (NMDAR), alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPAR), and gamma aminobutyric acid type B receptor (GABABR) antibodies.

 

Autoantibodies recognizing onconeural proteins shared by neurons, glia, or muscle (eg, antineuronal nuclear antibody, type 1: ANNA 1; collapsin response-mediator protein-5 neuronal: CRMP-5-IgG; N-type calcium channel antibody), also serve as markers of paraneoplastic or idiopathic autoimmune epilepsies. A specific neoplasm is often predictable by the individual patient's autoantibody profile.

 

Suspicion for autoimmune epilepsy on clinical grounds justifies comprehensive evaluation of cerebrospinal fluid (CSF) and serum for neural autoantibodies. Selective testing for individual autoantibodies is not advised because each is individually rare, and a timely diagnosis is critical. Collectively, the antibodies tested for in the autoimmune epilepsy evaluations represent a broad spectrum of treatable disorders, some of which are associated with occult cancer. Testing of CSF for autoantibodies is particularly helpful when serum testing is negative, though in some circumstances testing both serum and CSF simultaneously is pertinent. Testing of CSF is recommended for some antibodies in particular (such as NMDA-R antibody and GFAP-IgG) because CSF testing is both more sensitive and specific. In contrast, serum testing for LGI1 antibody is more sensitive than CSF testing. Failure to detect a neural antibody does not exclude the diagnosis of autoimmune epilepsy when other clinical clues exist. A trial of immunotherapy is justifiable in those cases.

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.

Test ID

Reporting Name

Methodology

Reference Value

AMPCC

AMPA-R Ab CBA, CSF

Cell-binding assay (CBA)

Negative

AMPHC

Amphiphysin Ab, CSF

Indirect immunofluorescence assay (IFA)

<1:2

AGN1C

Anti-Glial Nuclear Ab, Type 1

IFA

<1:2

ANN1C

Anti-Neuronal Nuclear Ab, Type 1

IFA

Negative at <1:2

ANN2C

Anti-Neuronal Nuclear Ab, Type 2

IFA

<1:2

ANN3C

Anti-Neuronal Nuclear Ab, Type 3

IFA

<1:2

CS2CC

CASPR2-IgG CBA, CSF

CBA

Negative

CRMC

CRMP-5-IgG, CSF

IFA

<1:2

DPPIC

DPPX Ab IFA, CSF

IFA

Negative

GABCC

GABA-B-R Ab CBA, CSF

CBA

Negative

GD65C

GAD65 Ab Assay, CSF

Radioimmunoassay (RIA)

< or =0.02 nmol/L

Reference values apply to all ages.

GFAIC

GFAP IFA, CSF

IFA

Negative

LG1CC

LGI1-IgG CBA, CSF

CBA

Negative

GL1IC

mGluR1 Ab IFA, CSF

IFA

Negative

NMDCC

NMDA-R Ab CBA, CSF

CBA

Negative

PCTRC

Purkinje Cell Cytoplasmc Ab Type Tr

IFA

<1:2

PCA2C

Purkinje Cell Cytoplasmic Ab Type 2

IFA

<1:2

Reflex Information:

Test ID

Reporting Name

Methodology

Reference Value

AGNBC

AGNA-1 Immunoblot, CSF

Immnuoblot (IB)

Negative

AMPIC

AMPA-R Ab IF Titer Assay, CSF

IFA

<1:2

AMIBC

Amphiphysin Immunoblot, CSF

IB

Negative

AN1BC

ANNA-1 Immunoblot, CSF

IB

Negative

AN2BC

ANNA-2 Immunoblot, CSF

IB

Negative

 

 

 

 

CRMWC

CRMP-5-IgG Western Blot, CSF

Western blot

Negative

DPPCC

DPPX Ab CBA, CSF

CBA

Negative

DPPTC

DPPX Ab IFA Titer, CSF

IFA

<1:2

GABIC

GABA-B-R Ab IF Titer Assay, CSF

IFA

<1:2

GFACC

GFAP CBA, CSF

CBA

Negative

GFATC

GFAP IFA Titer, CSF

IFA

<1:2

GL1CC

mGluR1 Ab CBA, CSF

CBA

Negative

GL1TC

mGluR1 Ab IFA Titer, CSF

IFA

<1:2

NMDIC

NMDA-R Ab IF Titer Assay, CSF

IFA

Negative at <1:2

PC1BC

PCA-1 Immunoblot, CSF

IB

Negative

PCTBC

PCA-Tr Immunoblot, CSF

IB

Negative

 

 

 

 

PCA1C

Purkinje Cell Cytoplasmic Ab Type 1

IFA

<1:2

 

Neuron-restricted patterns of IgG staining that do not fulfill criteria for ANNA-1, ANNA-2, ANN3C, CA-1, PCA-2, or PCA-Tr may be reported as "unclassified antineuronal IgG." Complex patterns that include nonneuronal elements may be reported as "uninterpretable."

 

Note: CRMP-5 titers lower than 1:2 are detectable by recombinant CRMP-5 Western blot analysis. CRMP-5 Western blot analysis will be done on request on stored spinal fluid (held 4 weeks). This supplemental testing is recommended in cases of chorea, vision loss, cranial neuropathy, and myelopathy. Call the Neuroimmunology Laboratory at 800-533-1710 to request CRMP-5 Western blot.

Interpretation
Provides information to assist in interpretation of the test results

Antibodies specific for neuronal, glial, or muscle proteins are valuable serological markers of autoimmune epilepsy and of a patient's immune response to cancer. These autoantibodies are not found in healthy subjects, and are usually accompanied by subacute neurological symptoms and signs. It is not uncommon for more than 1 of the following autoantibodies to be detected in patients with autoimmune epilepsy:

-Plasma membrane antibodies (N-methyl-D-aspartate: NMDA receptor; 2-amino-3-[5-methyl-3-oxo-1,2-oxazol-4-yl] propanoic acid: AMPA receptor; gamma-amino butyric acid: GABA-B receptor). These autoantibodies are all potential effectors of dysfunction.

-Neuronal nuclear autoantibody, type 1 (ANNA-1) or type 3 (ANNA-3).

-Neuronal or muscle cytoplasmic antibodies (amphiphysin, Purkinje cell antibody-type 2: PCA-2, collapsin response-mediator protein-5 neuronal: CRMP-5-IgG, or glutamic acid decarboxylase: GAD65 antibody).

 

A rising autoantibody titer in a previously seropositive patient suggests cancer recurrence.

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

Negative results do not exclude autoimmune epilepsy or cancer.

 

This evaluation does not detect Ma2 antibody (alias MaTa). Ma2 antibody has been described in patients with brainstem and limbic encephalitis in the context of testicular germ cell neoplasms. Scrotal ultrasound is advisable in men who present with unexplained subacute encephalitis.

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

1. Quek AL, Britton JW, McKeon A, et al: Autoimmune epilepsy: clinical characteristics and response to immunotherapy. Arch Neurol 2012 May;69(5):582-593

2. Yu Z, Kryzer TJ, Griesmann GE, et al: CRMP-5 neuronal autoantibody: marker of lung cancer and thymoma-related autoimmunity. Ann Neurol 2001 Feb;49(2):146-154; Editorial: 49:141-142

3. Pittock SJ, Yoshikawa H, Ahlskog JE, et al: Glutamic acid decarboxylase autoimmunity with brainstem, extrapyramidal and spinal cord dysfunction. Mayo Clin Proc 2006;81:1207-1214

4. Klein CJ, Lennon VA, Aston PA, et al: Insights from LGI1 and CASPR2 potassium channel complex autoantibody subtyping. JAMA Neurol 2013;70(2):229-234

5. Lancaster E, Martinez-Hernandez E, Dalmau J: Encephalitis and antibodies to synaptic and neuronal cell surface proteins. Neurology 2011;77(2):179-189

Special Instructions
Library of PDFs including pertinent information and forms related to the test

Method Description
Describes how the test is performed and provides a method-specific reference

Indirect Immunofluorescence Assay:

Before testing, patient's specimen is pre-diluted. After applying to a composite substrate of frozen mouse tissues (brain, kidney, and gut) and washing, fluorescein-conjugated goat-antihuman IgG is applied to detect the distribution and pattern of patient IgG binding.(Pittock SJ, Kryzer TJ, Lennon VA: Paraneoplastic antibodies coexist and predict cancer, not neurological syndrome. Ann Neurol 2004;56:715-719; 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)

 

Radioimmunoassay:

Duplicate aliquots of patient specimen are incubated with I(125)-labeled antigen. Immune complexes, formed by adding secondary (goat) antihuman immunoglobulin, are pelleted by centrifugation and washed. Gamma emission from the washed pellet is counted, and mean counts per minute (cpm) are compared with results yielded by high positive and negative control sera. Specimen yielding cpm higher than the background cpm yielded by normal human specimen are retested to confirm positivity and titrated as necessary to obtain a value in the linear range of the assay. The antigen binding capacity (nmol per liter) is calculated from the cpm precipitated at a dilution yielding a linear range value.(Griesmann GE, Kryzer TJ, Lennon VA: Autoantibody profiles of myasthenia gravis and Lambert-Eaton myasthenic syndrome. In Manual of Clinical and Laboratory Immunology. Sixth edition. Edited by NR Rose, RG Hamilton, et al. ASM Press, 2002, pp 1005-1012; Walikonis JE, Lennon VA: Radioimmunoassay for glutamic acid decarboxylase [GAD65] autoantibodies as a diagnostic aid for stiff-man syndrome and a correlate of susceptibility to type 1 diabetes mellitus. Mayo Clin Proc 1998 December;73[12]:1161-1166; Jones AL, Flanagan EP, Pittock SJ, et al: Responses to and Outcomes of Treatment of Autoimmune Cerebellar Ataxia in Adults. JAMA Neurol 2015 Nov;72[11]:1304-1312 doi: 10.1001/jamaneurol.2015.2378)

 

Western Blot:

Neuronal antigens extracted aqueously from adult rat cerebellum, full-length recombinant human collapsin response-mediator protein-5 (CRMP-5), or full-length recombinant human amphiphysin protein is denatured, reduced, and separated by electrophoresis on 10% polyacrylamide gel. IgG is detected autoradiographically by enhanced chemiluminescence.(Yu Z, Kryzer TJ, Griesmann GE, et al: CRMP-5 neuronal autoantibody: marker of lung cancer and thymoma-related autoimmunity. Ann Neurol 2001 February;49[2]:146-154; Dubey D, Jitprapaikulsan J, Bi H, et al: Amphiphysin-IgG autoimmune neuropathy: A recognizable clinicopathologic syndrome. Neurology 2019 Oct 17 pii: 10.1212/WNL.0000000000008472. doi: 10.1212/WNL.0000000000008472)

 

Immunoblot:

All steps are performed at ambient temperature (18-28 degrees C) utilizing the EUROBlot One instrument. Diluted patient specimen (1:12.5) is added to test strips (strips containing recombinant antigen manufactured and purified using biochemical methods) in individual channels and incubated for 30 minutes. Positive specimens will bind to the purified recombinant antigen and negative specimens will not bind. Strips are washed to remove unbound antibodies and then incubated with antihuman IgG antibodies (alkaline phosphatase-labelled) for 30 minutes. The strips are again washed to remove unbound antihuman IgG antibodies and nitroblue tetrazolium chloride/5-bromo-4-chloro-3-indolylphosphate (NBT/BCIP) substrate is added. Alkaline phosphatase enzyme converts the soluble substrate into a colored insoluble product on the membrane to produces a black band. Strips are digitized via picture capture on the EUROBlot One instrument and evaluated with the EUROLineScan software.(O'Connor K, Waters P, Komorowski L, et al: GABAA receptor autoimmunity: A multicenter experience. Neurol Neuroimmunol Neuroinflamm 2019 Apr 4;6[3]:e552 doi: 10.1212/NXI.0000000000000552)

 

Cell-Binding Assay:

Patient specimen is applied to a composite slide containing transfected and nontransfected HEK-293 cells. After incubation and washing, fluorescein-conjugated goat-antihuman IgG is applied to detect the presence of patient IgG binding.(Package insert: : IIFT: Neurology Mosaics, Instructions for the indirect immunofluorescence test. EUROIMMUN, FA_112d-1_A_UK_C13, 02/2019)

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.

AMPHC, AGN1C, ANN1C, ANN2C, ANN3C, CRMC, DPPIC, GD65C, GFAIC, GL1IC, PCTRC, PCA2C, AMPIC, DPPTC, GABIC, GFATC, GL1TC, NMDIC, PCA1C: Monday through Sunday

 

AMPCC, CS2CC, GABCC, LG1CC, NMDCC, DPPCC: Monday through Thursday, Sunday

 

GL1CC: Monday, Thursday

 

AGNBC, AMIBC, AN1BC, AN2BC, PC1BC, PCTBC: Monday through Friday

 

CRMWC: Monday through Thursday

 

GFACC: Monday, Wednesday, Friday

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.

5 to 10 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 Regional Manager. 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. This test 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.

86255x16

86341 x1

84182-AGNBC (if appropriate)

86256-AMPIC (if appropriate)

84182-AMIBC (if appropriate)

84182-AN1BC (if appropriate)

84182-AN2BC (if appropriate)

84182-CRMWC (if appropriate)

86255-DPPCC (if appropriate)

86256-DPPTC (if appropriate)

86256-GABIC (if appropriate)

86255-GFACC (if appropriate)

86256-GFATC (if appropriate)

86255-GL1CC (if appropriate)

86256-GL1TC (if appropriate)

86256-NMDIC (if appropriate)

84182-PC1BC (if appropriate)

84182-PCTBC (if appropriate)

86255-PCA1C (if appropriate)

LOINC® Information

Test Id Test Order Name Order LOINC Value
EPC2 Epilepsy-Autoimmune Evaluation, CSF In Process
Result Id Test Result Name Result LOINC Value
Result LOINC Value Tooltip

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