Days Set Up
Sunday- Thursday
Analytic Time

3 - 7 days

MiChart Code
Glutamic Acid Decarboxylase Antibody
Soft Order Code

Test Updated:


GAD (Glutamic Acid Decarboxylase) Antibody
GAD 65
Glutamate Decarboylase AB
Islet Cell Cytoplasmic Antibody
Stiffman Syndrome
GAD65 Ab Assay, S/CSF
GAD65 Ab Assay, CSF
GAD65 Ab Assay, Serum

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Find a Requisition

All specimens should be accompanied by a requisition.

Submitting Specimens

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Order Kits and Supplies

MLabs provides all the supplies necessary for the collection of specimens.

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Test Overview

Test Methodology

Radioimmunoassay (RIA)

Test Usage

Assessing susceptibility to autoimmune (type 1) diabetes mellitus and related endocrine disorders. Distinguishing between type 1 and type 2 diabetes. Confirming diagnosis of stiff-man syndrome and related autoimmune encephalomyelopathies.

Reference Range

< or = 0.02 nmol/L

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Specimen Requirements

Collection Offsite

Collect specimen in red top or SST tube. Centrifuge, aliquot serum into a plastic vial and refrigerate.

Red Top Tube
Yellow Top Tube
Normal Volume
1.5 mL serum
Minimum Volume
1 mL serum

Billing Information

CPT Code
Pro Fee Code

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Our High Standard

Quality that sets us apart

As the reference laboratory division of Michigan Medicine's Department of Pathology, MLabs shares the institution's commitment to applying established quality principles to clinical laboratory testing. Like other large organizations in complex, consequential fields, we rely on an established approach to monitor quality throughout the testing process.