Glutamic Acid Decarboxylase-65 Antibody : 34878

Test Code

GADABQ or 34878

CPT Codes
86341

Instructions

Serum separator tube or plain red tube.

Transport Container

Centrifuge serum separator tube and transport. If plain red, centrifuge and aliquot 1 mL serum (Min: 0.5 mL) into a standard transport tube.

Transport Temperature

Refrigerated.

Specimen Stability

Ambient: 7 days; Refrigerated: 14 days; Frozen: 60 days

Methodology
Enzyme Linked Immunosorbent Assay (ELISA)

Setup Schedule

Sunday - Friday

Report Available

3-5 days (From receipt at performing laboratory)

Limitations

GAD-65 antibodies are detected in 20% of diabetic twins who remain disease-free for long periods of time and in 8% of healthy individuals.

Reference Range

less than 5 IU/mL

Clinical Significance

Glutamic acid decarboxylase (GAD-65) antibody is useful to diagnose insulin dependent diabetes mellitus [Type I diabetes (autoimmune-mediated diabetes)] to assess risk for development of Type I diabetes, to predict onset of Type I diabetes, and risk of development of related endocrine disorders, e.g., thyroiditis. Before clinical onset, Type I diabetes is characterized by lymphocytic infiltration of the islet cells, and by circulating autoantibodies against a variety of islet cell antigens, including GAD-65, IA-2 (a tyrosine phosphatase-like protein), and insulin (IAA).

Performing Laboratory
Quest Diagnostics

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.