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Glutamic acid decarboxylase Ab

Lab Section:  Sendout Reference  
Lab Location:  Sendout
Reference Lab: Mayo 
Test ID: LAB650 
Methodology: Radioimmunoassay (RIA)
Schedule: Sunday through Thursday; 10 p.m.
Reported: 10 days
Specimen Requirements:  Collection: 3.0 mL Blood in a Red Top Tube.
Pediatric volume: 1 mL.
SST tube also acceptable
Unacceptable conditions: Gross Hemolysis; Gross Lipemia; Gross Icterus
Stability: Ambient 72 hours; Refrigerate 28 days; Frozen 28 days

Notes: 

Clinical Indications: Glutamic acid decarboxylase (GAD) is a neuronal enzyme involved in the synthesis of the neurotransmitter gamma-aminobutyric acid (GABA). Antibodies directed against the 65-kd isoform of GAD (GAD65) are seen in a variety of autoimmune neurologic disorders including stiff-man (Moersch-Woltman) syndrome, autoimmune cerebellitis, brain stem encephalitis, seizure disorders, neuromyelitis optica and other myelopathies, myasthenia gravis, Lambert-Eaton syndrome, and dysautonomia. GAD65 antibody is also the major pancreatic islet antibody and an important serological marker of predisposition to type 1 diabetes. GAD65 autoantibody also serves as a marker of predisposition to other autoimmune disease that occur with type 1 diabetes, including thyroid disease (eg, thyrotoxicosis, Grave disease, Hashimoto thyroiditis, hypothyroidism), pernicious anemia, premature ovarian failure, Addison disease, (idiopathic adrenocortical failure) and vitiligo.

Reference Interval:  See patient report or consult reference laboratory website.
CPT Code(s): 86341
Last Changed: 11/01/2016 11:11:17
Last Reviewed: 12/26/2016 23:47:32