Sign in →

Test Code GID2 Gastrointestinal Dysmotility, Autoimmune/Paraneoplastic Evaluation, Serum


Ordering Guidance


Multiple neurological phenotype-specific autoimmune/paraneoplastic evaluations are available. For more information as well as phenotype-specific testing options, refer to Autoimmune Neurology Test Ordering Guide.

 

When more than one evaluation is ordered on the same order number the duplicate will be canceled.

 

For a list of antibodies performed with each evaluation, see Autoimmune Neurology Antibody Matrix.

 

This test should not be requested in patients who have recently received radioisotopes, therapeutically or diagnostically, because of potential assay interference. The specific waiting period before specimen collection will depend on the isotope administered, the dose given, and the clearance rate in the individual patient. Specimens will be screened for radioactivity prior to analysis. Radioactive specimens received in the laboratory will be held 1 week and assayed if sufficiently decayed or canceled if radioactivity remains.



Necessary Information


Provide the following information:

-Relevant clinical information

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



Specimen Required


Patient Preparation: For optimal antibody detection, specimen collection is recommended prior to initiation of immunosuppressant medication or intravenous immunoglobulin (IVIg) treatment.

Supplies: Sarstedt Aliquot Tube, 5 mL (T914)

Collection Container/Tube:

Preferred: Red top

Acceptable: Serum gel

Submission Container/Tube: Plastic vial

Specimen Volume: 4 mL

Collection Instructions: Centrifuge and aliquot serum into a plastic vial.


Useful For

Investigating unexplained weight loss, early satiety, anorexia, nausea, vomiting, constipation, or diarrhea in a patient with a past or family history of cancer or autoimmunity

 

Directing a focused search for cancer

 

Investigating gastrointestinal symptoms that appear in the course or wake of cancer therapy, not explainable by recurrent cancer, metastasis, or therapy; detection of autoantibodies on this profile helps differentiate autoimmune gastrointestinal dysmotility from the effects of chemotherapy

 

Detecting early evidence of cancer recurrence in previously seropositive patients who have a rising titer of 1 or more autoantibodies

Profile Information

Test ID Reporting Name Available Separately Always Performed
AGIDI GI Dysmotility, Interpretation, S No Yes
GANG AChR Ganglionic Neuronal Ab, S No Yes
ANN1S Anti-Neuronal Nuclear Ab, Type 1 No Yes
APBIS AP3B2 IFA, S No Yes
CS2CS CASPR2-IgG CBA, S No Yes
CRMS CRMP-5-IgG, S No Yes
DPPCS DPPX Ab CBA, S Yes Yes
LG1CS LGI1-IgG CBA, S No Yes
PCAB2 Purkinje Cell Cytoplasmic Ab Type 2 No Yes

Reflex Tests

Test ID Reporting Name Available Separately Always Performed
AN1BS ANNA-1 Immunoblot, S No No
AN2BS ANNA-2 Immunoblot, S No No
CRMWS CRMP-5-IgG Western Blot, S Yes No
DPPTS DPPX Ab IFA Titer, S No No
AN1TS ANNA-1 Titer, S No No
APBCS AP3B2 CBA, S No No
APBTS AP3B2 IFA Titer, S No No
CRMTS CRMP-5-IgG Titer, S No No
PC2TS PCA-2 Titer, S No No

Testing Algorithm

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

 

If the IFA pattern suggests antineuronal nuclear antibody (ANNA)-1, then the ANNA-1 immunoblot, ANNA-1 titer, and ANNA-2 immunoblot will be performed at an additional charge.

 

If the IFA pattern suggests AP3B2 adaptor protein 3 beta2) antibodies, then the AP3B22 cell binding assay (CBA) and AP3B22 titer will be performed at an additional charge.

 

If the IFA pattern suggests PCA-2 antibody, then the PCA-2 IFA titer will be performed at an additional charge.

 

If dipeptidyl-peptidase-like protein-6 antibody (DPPX) antibody CBA result is positive, then the DPPX titer will be performed at an additional charge.

 

For more information see Autoimmune/Paraneoplastic Gastrointestinal Dysmotility Evaluation Algorithm.

Method Name

ANN1S, AN1TS, APBIS, APBTS, DPPTS, CRMS, CRMTS, PCAB2, PC2TS: Indirect Immunofluorescence Assay (IFA)

 

APBCS, CS2CS, LG1CS, DPPCS: Cell Binding Assay (CBA)

 

CRMWS: Western Blot (WB)

 

AN1BS, AN2BS: Immunoblot (IB)

 

GANG: Radioimmunoassay (RIA)

Reporting Name

GI Dysmotility, Autoimm/Paraneo, S

Specimen Type

Serum

Specimen Minimum Volume

2 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Serum Refrigerated (preferred) 28 days
  Frozen  28 days
  Ambient  72 hours

Reject Due To

Gross hemolysis Reject
Gross lipemia Reject
Gross icterus Reject

Clinical Information

Autoimmune gastrointestinal dysmotility (AGID) is a limited form of dysautonomia (also known as autoimmune autonomic ganglionopathy or neuropathy) that is sometimes a paraneoplastic disorder. Neoplasms most frequently found are lung cancer, thymoma, and miscellaneous adenocarcinomas. Diagnosis is confirmed by objective abnormalities on gastrointestinal (GI) motility studies (eg, gastric, small intestinal, or colonic nuclear transit studies; esophageal, gastroduodenal, or colonic manometry or anorectal manometry with balloon expulsion). These disorders target autonomic postganglionic synaptic membranes and, in some cases, ganglionic neurons and autonomic nerve fibers, and may be accompanied by sensory small fiber neuropathy. Onset may be subacute or insidious. There may be additional manifestations of dysautonomia (eg, impaired pupillary light reflex, anhidrosis, orthostatic hypotension, sicca manifestations, and bladder dysfunction) or signs of other neurologic impairment. Autonomic reflex testing and a thermoregulatory sweat test are valuable aids in the documentation of objective abnormalities.

 

The serological profile of AGID may include autoantibodies specific for onconeural proteins found in the nucleus, cytoplasm, or plasma membrane of neurons or muscle. Some of these autoantibodies are highly predictive of an underlying cancer. A commonly encountered autoantibody marker of AGID is the ganglionic neuronal alpha-3-acetylcholine receptor (alpha-3-AChR) autoantibody. The pathogenicity of this autoantibody was demonstrated in rabbits immunized with a recombinant extracellular fragment of the alpha-3-AChR subunit and in mice injected with IgG from high-titered alpha-3-AChR autoantibody-positive rabbit or human sera. A direct relationship between antibody titer and severity of dysautonomia occurs in both experimental animals and patients. Patients with high alpha-3-AChR autoantibody values (>1.0 nmol/L) generally present with profound pandysautonomia, and those with lower alpha-3-AChR autoantibody values may have limited autoimmune dysautonomia or other neurological signs and symptoms.

 

Importantly, cancer is detected in 30% of patients with alpha-3-AChR autoantibody. Cancer risk factors include the patient's previous or family history of cancer, history of smoking, or social and environmental exposure to carcinogens. Early diagnosis and treatment of the neoplasm favor less morbidity from the GI dysmotility disorder. The cancers recognized most frequently with alpha-3-AChR autoantibody include lymphoma and adenocarcinomas of breast, lung, prostate, and GI tract. A specific neoplasm is often predictable when a patient's autoantibody profile includes other autoantibodies to onconeural proteins shared by neurons, glia, or muscle. Small-cell lung carcinoma is found in 80% of patients who are antineuronal nuclear antibody-type 1 (ANNA-1, also known as anti-Hu) positive, and 23% of patients who are ANNA-1 positive have GI dysmotility. The most common GI manifestation is gastroparesis, but the most dramatic is pseudoobstruction.

Reference Values

Test ID

Reporting Name

Methodology*

Reference Value

AGIDI

GI Dysmotility, Interpretation, S

Medical interpretation

Interpretive report

GANG

AChR Ganglionic Neuronal Ab, S

RIA

≤0.02 nmol/L

ANN1S

Anti-Neuronal Nuclear Ab, Type 1

IFA

Negative

APBIS

AP3B2 IFA, S

IFA

Negative

CS2CS

CASPR2-IgG CBA, S

CBA

Negative

CRMS

CRMP-5-IgG, S

IFA

Negative

DPPCS

DPPX Ab CBA, S

CBA

Negative

LG1CS

LGI1-IgG CBA, S

CBA

Negative

PCAB2

Purkinje Cell Cytoplasmic Ab Type 2

IFA

Negative

Reflex Information:

Test ID

Reporting Name

Methodology*

Reference Value

AN1BS

ANNA-1 Immunoblot, S

IB

Negative

AN1TS

ANNA-1 Titer, S

IFA

<1:240

AN2BS

ANNA-2 Immunoblot, S

IB

Negative

APBCS

AP3B2 CBA, S

CBA

Negative

APBTS

AP3B2 IFA Titer, S

IFA

<1:240

CRMTS

CRMP-5-IgG Titer, S

IFA

<1:240

CRMWS

CRMP-5-IgG Western Blot, S

WB

Negative

DPPTS

DPPX Ab IFA Titer, S

IFA

<1:240

PC2TS

PCA-2 Titer, S

IFA

<1:240

 

*Methodology abbreviations used:

Immunofluorescence assay (IFA)

Cell-binding assay (CBA)

Western blot (WB)

Radioimmunoassay (RIA)

Immunoblot (IB)

 

Neuron-restricted patterns of IgG staining that do not fulfill criteria for ANNA-1, CRMP-5-IgG, or PCA-2 may be reported as "unclassified anti-neuronal IgG." Complex patterns that include nonneuronal elements may be reported as "uninterpretable."

 

CRMP-5 titers lower than 1:240 are detectable by recombinant CRMP-5 Western blot analysis. CRMP-5 Western blot analysis will be done on request on stored serum (held for 4 weeks). This supplemental testing is recommended in cases of chorea, vision loss, cranial neuropathy, and myelopathy. Call 1-800-533-1710 to request CRMP-5 Western blot.

Interpretation

Antibodies directed at onconeural proteins shared by neurons, muscle, and certain cancers are valuable serological markers of a patient's immune response to cancer. They are not found in healthy subjects and are usually accompanied by subacute signs and symptoms. It is not uncommon for more than one antibody to be detected. Three classes of antibodies are recognized (the individual antibodies from each class included in the profile are denoted in parentheses):

-Antineuronal nuclear autoantibody-type 1

-Neuronal and muscle cytoplasmic (collapsin response-mediator protein-5)

-Plasma membrane cation channel (neuronal ganglionic alpha-3-acetylcholine receptor).

These autoantibodies are potential effectors of autoimmune gastrointestinal dysmotility.

Cautions

Negative results do not exclude autoimmune gastrointestinal dysmotility or cancer.

 

Intravenous immunoglobulin (IVIg) treatment prior to the serum collection may cause a false-positive result.

Method Description

Indirect Immunofluorescence Assay:

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;4(5):e385. doi:10.1212/NXI.0000000000000385)

 

Radioimmunoassay:

(125)I-labeled recombinant human antigens or labeled receptors are incubated with patient specimen. After incubation, anti-human IgG is added to form an immunoprecipitate. The amount of (125)I-labeled antigen in the immunoprecipitate is measured using a gamma-counter. The amount of gamma emission in the precipitate is proportional to the amount of antigen-specific IgG in the specimen. Results are reported as units of precipitated antigen (nmol) per liter of patient sample.(Griesmann GE, Kryzer TJ, Lennon VA. Autoantibody profiles of myasthenia gravis and Lambert-Eaton myasthenic syndrome. In: Rose NR, Hamilton RG, et al, eds. Manual of Clinical and Laboratory Immunology. 6th ed. ASM Press; 2002:1005-1012; Jones AL, Flanagan EP, Pittock SJ, et al. Responses to and outcomes of treatment of autoimmune cerebellar ataxia in adults. JAMA Neurol. 2015;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, Kim K, Benarroch EE, Lennon VA l. CRMP-5 neuronal autoantibody: marker of lung cancer and thymoma-related autoimmunity. Ann Neurol. 2001;49[2]:146-154; Dubey D, Jitprapaikulsan J, Bi H, et al. Amphiphysin-IgG autoimmune neuropathy: A recognizable clinicopathologic syndrome. Neurology. 2019;93(20):e1873-e1880. doi:10.1212/WNL.0000000000008472)

 

Immunoblot:

All steps are performed at ambient temperature (18-28° C) utilizing the EUROBlot One instrument. Diluted patient serum (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 serum samples will bind to the purified recombinant antigen and negative serum samples will not bind. Strips are washed to remove unbound serum antibodies and then incubated with antihuman IgG antibodies (alkaline phosphatase-labeled) for 30 minutes. The strips are again washed to remove unbound antihuman IgG antibodies and nitroblue tetrazolium chloride/5-bromo-4-chloro-3-indolyl phosphate substrate is added. Alkaline phosphatase enzyme converts the soluble substrate into a colored insoluble product on the membrane to produce 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;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)

Report Available

8 to 12 days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test Classification

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

83519

86255 x 7

84182 AN1BS (if appropriate)

86256 AN1TS (if appropriate)

84182 AN2BS (if appropriate)

86255 APBCS (if appropriate)

86256 APBTS (if appropriate)

86256 CRMTS (if appropriate)

84182 CRMWS (if appropriate)

86255 DPPCS (if appropriate)

86256 DPPTS (if appropriate)

86256 PC2TS (if appropriate)

LOINC Code Information

Test ID Test Order Name Order LOINC Value
GID2 GI Dysmotility, Autoimm/Paraneo, S 97557-3

 

Result ID Test Result Name Result LOINC Value
34269 GI Dysmotility, Interpretation, S 69048-7
80150 ANNA-1, S 33615-6
83077 CRMP-5-IgG, S 72504-4
84321 AChR Ganglionic Neuronal Ab, S 94694-7
83138 PCA-2, S 84925-7
64279 LGI1-IgG CBA, S 94287-0
64281 CASPR2-IgG CBA, S 94285-4
64933 DPPX Ab CBA, S 94676-4
615863 AP3B2 IFA, S 101907-4
618899 IFA Notes 48767-8