Anti-insulin antibody testDefinition:
The anti-insulin antibody test checks to see if your body has produced antibodies against insulin.
Insulin antibodies - serum; Insulin Ab test
How the Test is Performed:
A blood sample is needed.
How to Prepare for the Test:
No special preparation is necessary.
How the Test will Feel:
When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away.
Why the Test is Performed:
This test may be performed if you have or are at risk for type 1 diabetes . It also may be done if you appear to have an allergic response to insulin, or if insulin no longer seems to control your diabetes.
Normally, there are no antibodies against insulin in your blood.
Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your doctor about the meaning of your specific test results.
What Abnormal Results Mean:
If you have IgG and IgM antibodies against insulin, your body reacts as if the insulin is foreign. This may make insulin less effective, or not effective at all. This is because the antibody prevents the insulin from working the right way in your cells. As a result, your blood sugar can be unusually high.
The antibodies can also prolong the effect of insulin by releasing some insulin long after your meal has been absorbed. This can put you at risk for low blood sugar.
If the test shows a high level of IgE antibody against insulin, your body has developed an allergic response to the medication. This could put you at risk for skin reactions at the site of the insulin injection. Or you can develop more severe reactions that affect your blood pressure or breathing.
Other medicines, such as antihistamines or low-dose injectable steroids, may help to lessen the reaction. If reactions have been severe, you may need a treatment process called desensitization.
Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight but may include:
- Excessive bleeding
- Fainting or feeling light-headed
- Hematoma (blood accumulating under the skin)
- Infection (a slight risk any time the skin is broken)
Eisenbarth GS, Buse JB. Type 1 diabetes mellitus. In: Melmed S, Polonsky KS, Larsen PR, Kronenberg HM, eds. Williams Textbook of Endocrinology. 12th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 32.