Glutamic Acid Decarboxylase (GAD65) Antibody, Serum/Plasma (Qualitative Line Blot)
This test measures antibodies against GAD65, a protein linked to autoimmune conditions affecting the pancreas. It helps diagnose or monitor type 1 diabetes or related autoimmune disorders.
["This test may help identify autoimmune conditions affecting the pancreas."]
Key facts at a glance
- LOINC
- 81725-4
- Short code
- GAD65 Ab Ser Ql Line blot
- Synonyms
- GAD65 Ab Ser Ql Line blot
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- line-blot
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why Is This Test Done?
Your healthcare provider may order this test if you have symptoms of type 1 diabetes, such as frequent urination, extreme thirst, unexplained weight loss, or fatigue. It may also be used in patients with unexplained pancreatic issues or other autoimmune conditions suspected to involve GAD65 antibodies.
What Does a Positive Result Mean?
A positive result suggests the presence of GAD65 antibodies, which can indicate an autoimmune response targeting pancreatic cells. This finding is often associated with type 1 diabetes or related autoimmune disorders, though it may not confirm the diagnosis alone.
What Does a Negative Result Mean?
A negative result means no detectable GAD65 antibodies were found in your sample. However, this does not rule out type 1 diabetes or other autoimmune conditions—other tests or follow-up may be needed.
How Is This Test Performed?
A blood sample is drawn from a vein in your arm. The sample is then tested using a line blot assay to detect GAD65 antibodies. This method detects the presence or absence of antibodies without providing a specific quantity.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
GAD65 antibodies are strongly associated with type 1 diabetes and other autoimmune conditions affecting the pancreas, such as insulinoma or autoimmune pancreatitis. Their presence can support a diagnosis of these conditions, but additional testing (e.g., glucose monitoring, C-peptide levels) may be required for confirmation. Early detection can help manage symptoms and prevent complications.
Short name
GAD65 Antibody Screening
Frequently asked questions
How long does it take to get results from this test?
Can I eat or drink before this test?
Is this test painful?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy