AGA stands for antigliadin antibodies, which are specific antibodies produced by the body in response to contact with gliadin, a part of the gluten molecule. IgG stands for immunoglobulin G, which are general-purpose antibody molecules.
A positive AGA-IgG blood test indicates that the body may be mounting an immune system response to gluten ingestion, but it’s considered less specific than other celiac blood tests. However, a positive AGA-IgG test can indicate celiac disease in a patient with IgA deficiency, which is a problem with your immune system that leaves you more susceptible to infections.
Uses
Since the AGA-IgG blood test can show your body is reacting to gluten (even if that reaction is not the specific one found in celiac disease), some physicians use the test as a tool to help them diagnose non-celiac gluten sensitivity.
However, medical research hasn’t shown the test to work all that well. In a 2015 study, clinicians compared blood test results from people with suspected non-celiac gluten sensitivity with results from people with celiac disease and people with neither condition.
After evaluating the data, they concluded that the AGA-IgG blood test isn’t a very sensitive test for non-celiac gluten sensitivity, which means it misses some people who actually do have the condition. The AGA-IgG test results can help with diagnosis, the researchers said, but only if the results are combined with other factors.
What Else Is the AGA-IgG Used For?
Elevated AGA-IgG levels have been found in some children diagnosed with autism. Studies have suggested autistic children who also have gastrointestinal symptoms can have higher levels of AGA-IgG than autistic children without digestive issues.
The AGA-IgG test also can be used to help diagnose gluten ataxia, a neurological autoimmune condition in which your body reacts to gluten ingestion by attacking a part of your brain. Gluten ataxia can cause a loss of coordination that affects your gait, your balance, and even your eyes. As such, physicians are generally advised to use the AGA-IgG blood test in concert with other blood tests if they suspect gluten ataxia.
