A Glutamic Acid Decarboxylase Autoantibodies (GAD) test is used to discover whether someone has either type-1 diabetes or Latent Autoimmune diabetes of adulthood. A GAD test is a blood test which measures whether the body is producing a type of antibody which destroys its own GAD cells. When testing for type-1 diabetes you will be tested for antibodies like islet cytoplasmic autoantibodies (ICAs), Insulinoma-associated-2 autoantibodies (IA-2As,) and Insulin autoantibodies (IAAs) which are prevalent in children than in adults. Type-1 diabetes is a result of an immune system malfunction. It occurs when the immune system attacks and destroys the Beta cells in the pancreas these cells produce insulin in the body and maintain the blood glucose levels. Once the beta cells are destroyed they cannot be repaired. Without insulin, glucose builds up in your blood, leaving your cells starved for energy. There are not confirmed symptoms for GAD but if you are being tested for GAD, you might have symptoms of diabetes which are: excessive thirst and hunger, frequent urination, irritability, blurry vision, fatigue, weakness, weight loss, and cuts or sores that take a long time to heal.
You may be advised to not drink or eat for six hours before the test. You may also be refrained from taking certain medicines till the test is not performed so that they don’t affect the diagnosis of the test. For the blood test, you should prefer wearing a sleeveless shirt or a loose fit full sleeve shirt comfortable to give the blood sample.
With the help of the test the doctor will know that If ICA, GADA, and/or IA-2A are present in a person with symptoms of diabetes, the diagnosis of type 1 diabetes is confirmed. Likewise, if IAA is present in a child with diabetes who is not insulin-treated, type 1 diabetes is the cause.
The lab technician taking a sample of your blood will: Wrap an elastic band around your upper arm to stop the flow of blood. This makes the veins below the band larger so it is easier to put a needle into the vein Clean the needle site with alcohol Put the needle into the vein. More than one needle stick may be needed. Attach a tube to the needle to fill it with blood Remove the band from your arm when enough blood is collected Put a gauze pad or cotton ball over the needle site as the needle is removed Put pressure on the site and then put on a bandage