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Test Code
GADAB
Test Name
Glutamic Acid Decarboxylase Antibody
CPT Codes
86341
Expected Turnaround Time
3 - 4 days
Clinical Utility

This test is intended for the semiquantitative determination of glutamic acid decarboxylase (GAD) antibody in human serum; it is useful as an aid in the diagnosis of type 1 diabetes mellitus (autoimmune mediated diabetes).
Specimen and Container Info

Specimen Type: Serum

  

Collection Container: Gold Top, Serum Separator

Alternate Collection Container: Red Top, Plain

Desired Specimen Volume: 0.5 mL
Collection Instructions
  1. Collect a gold top, serum separator tube via venipuncture.
Processing and Submission Instructions
  1.  Separate serum from cells.
  2. Transfer 0.5 mL of serum to a LabCorp PP transpak frozen purple tube.
Patient Preparation

This test may exhibit interference when sample is collected from a person who is consuming a supplement with a high dose of biotin (also termed as vitamin B7 or B8, vitamin H, or coenzyme R). It is recommended to ask all patients who may be indicated for this test about biotin supplementation. Patients should be cautioned to stop biotin consumption at least 72 hours prior to the collection of a sample.
Transport Instructions

Transport to the laboratory frozen. 
Stability Requirements

Room Temperature

14 days

Refrigerated

14 days

Frozen

14 days

Freeze/Thaw Cycles

 Stable x3
Causes for Rejection
  • Grossly hemolyzed
  • Grossly lipemic
Methodology
ELISA
Reference Intervals

See patient report.

Alternate Names
  •  GAD-65 Autoantibody
Reference Lab
Labcorp Of America Holdings
Testing Schedule
Monday-Friday
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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