Gliadin Antibody

What is the usefulness of gliadin antibody testing? What is gluten intolerance? And finally, what is the relation between these two? As much as 15% of the world population cannot digest wheat. It is said that wheat is a recent addition to the human diet, and a protein referred to as 'gluten' in it, is said to be the culprit behind gluten or wheat intolerance and related problems in these people. Is it the complete truth?

Understanding the Gliadin Antibody

One molecule of gluten consists of two molecules, i.e. glutenin and gliadin, and acts as a storage protein. All proteins contain polypeptides which are long chains of amino acids. In case of wheat, gliadin appears to the immune system as a harmful foreign body and is triggered to destroy it. Immune system produces gliadin antibodies, which are complex protein molecules, to deal with this threat and to neutralize it. The condition is termed celiac disease which is an autoimmune disease. It can be detected by measuring gliadin presence in the blood.

In small children, gluten intolerance, which may be called more appropriately as gliadin intolerance, causes damage to the villi of small intestine. These are finger like structures which are tasked with the absorption of nutrients from the food. The damage to the villi results in undernourishment of the child. In infants, gluten intolerance may appear with the introduction of solid food. Following are the gluten intolerance symptoms:

• Abdominal pain
• Bloating
• Diarrhea
• Flatulence
• Painful skin rashes
• Malabsorption symptoms
• Mouth sores
• Weight loss
• Fatigue

If the doctor suspects wheat intolerance as the cause of problems then he may advise to get gluten or wheat intolerance test done to detect gliadin in the blood serum. The gluten intolerance test is important one as many other diseases exhibits symptoms similar to the gluten intolerance symptoms. Sometimes an individual can go on eating the wheat products but never feel these symptoms.

Gliadin Test

In a wheat intolerant person, eating wheat products produces causes synthesis of the gliadin antibody such as Immunoglobulin A (IgA) and Immunoglobulin G (IgG). The blood test to detect these antibodies is simple and a small amount of blood is taken as sample to be tested.

• Immunoglobulin A (IgA): A distinctive characteristics of celiac diseases is the presence of IgA antibody in the blood sample. Response of the immune system to the presence of gliadin in the wheat causes the production of the IgA in the small intestine. Normally, the presence ranges from, 85 to 385 milligrams per deciliter, in case of IgA.
• Immunoglobulin G (IgG): Presence of gliadin antibody IgG, which may be with or without IgA, does not actually signifies gluten intolerance as it may be because of the other autoimmune diseases.
• Immunoglobulin E (IgE): These are detected typically in conditions signifying allergy such as urticaria, wheat-dependent exercise-induced anaphylaxis and asthma.

The procedure used to test the blood sample is called ELISA (enzyme-linked immunosorbent assay). To detect gliadin in the blood sample, a small amount of it is placed on a specially prepared plate, and thus, is brought in contact with certain chemicals. The chemical reaction between these produces change of color. Depending the intensity of the color, technicians can tell whether the antibodies are present in the blood sample or not. If it is then the doctor may advice to get further tests done such as the biopsy of the small intestine to collect evidence of the gliadin induced inflammation.

The treatment advised by the doctor, in this case, is wheat intolerance diet or gluten intolerance diet, which are aimed at bringing the gliadin level below 10, as it normally should be. The patient is asked to stop eating wheat products. It is no use avoiding this additional tests as these are important steps in detection of celiac diseases. The need is felt because of the gluten or wheat intolerance symptoms shared by some other diseases. What may first appear as a case of gluten intolerance may actually be due to some other disease, and without an accurate diagnosis, the patient may end up with an easy source (wheat) of nutrient cut off from his diet.