Glutamic Acid Decarboxylase Antibodies (GAD 65)
The Glutamic Acid Decarboxylase Antibodies (GAD 65) blood test measures antibodies directed against the GAD 65 enzyme, a protein involved in the production of gamma-aminobutyric acid (GABA), an important neurotransmitter that helps regulate nerve signalling. In some individuals, the immune system mistakenly targets this enzyme, producing antibodies that can interfere with normal function.
GAD 65 antibodies are most commonly associated with autoimmune conditions, particularly type 1 diabetes and other forms of autoimmune diabetes. They may also be seen in certain neurological autoimmune conditions. Testing helps identify autoimmune activity and supports diagnosis, classification, and management decisions.
- Price: £150
- Code: GAD65
- TAT: 8 Working Days
- Sample Type: Blood
What are GAD 65 antibodies?
Glutamic acid decarboxylase is an enzyme found in pancreatic beta cells and nerve tissue. It plays a key role in normal metabolic and neurological processes. When the immune system produces antibodies against GAD 65, it can damage cells involved in insulin production or nerve function.
The presence of GAD 65 antibodies suggests an autoimmune process rather than a lifestyle-related cause of disease. This distinction is particularly important when assessing different types of diabetes or unexplained neurological symptoms.
Why might I need a GAD 65 antibody test?
This test may be recommended if you have newly diagnosed diabetes and there is uncertainty about whether it is type 1, type 2, or latent autoimmune diabetes in adults (LADA). Identifying an autoimmune cause helps guide treatment decisions and long-term management.
GAD 65 antibody testing may also be used when investigating certain neurological symptoms, such as muscle stiffness, spasms, or unexplained neurological changes, where autoimmune involvement is being considered.
What do the results mean?
A positive GAD 65 antibody result indicates autoimmune activity and supports a diagnosis of autoimmune diabetes or another autoimmune condition, depending on the clinical context.
A negative result makes significant GAD-related autoimmune activity less likely but does not completely exclude all autoimmune causes. Results are interpreted alongside symptoms, blood glucose tests, and other antibody markers.
How is the test performed?
The GAD 65 antibody test is performed using a blood sample collected during a short appointment. The procedure is routine and well tolerated, and our clinical team will ensure you are comfortable throughout.
Do I need to prepare the test?
No special preparation or fasting is required for this test unless you have been advised otherwise.
FAQs
When will I receive my results?
Results are usually available within the stated turnaround time.
Should I discuss my results with a doctor?
Yes, results should always be reviewed with a qualified healthcare professional.
Why Choose Marylebone Diagnostic Centre?
Marylebone Diagnostic Centre provides specialist autoimmune antibody testing in a calm and supportive environment, with clear communication and careful interpretation of results.
Our experienced clinical team supports you in understanding your results and how they relate to your symptoms, diagnosis, and treatment options.
Book Your Folate (Serum) Test Today
If you require clarification of diabetes type or investigation of autoimmune causes, book your GAD 65 antibody blood test with Marylebone Diagnostic Centre.
