How is it assessed?
Blood tests
Blood tests for abnormal antibodies are used to identify which children need further testing for coeliac disease. Antibody blood tests may also be used at follow up visits to check whether the gluten free diet is being followed – the antibody tests become negative once gluten is no longer eaten.
The following blood tests are used -:
- tTGA testing – this measures IgA tissue transglutaminase antibody and is the main test used currently. This test may be falsely negative if there is IgA deficiency.
- EMA test – IgA endomysial antibody (EMA) test is used if the tTGA test is not clearly positive or negative – the result will be called ‘equivocal’ in medical evidence.
If either of these tests is positive, referral for intestinal biopsy will be made. If IgA deficiency is present, other antibody tests will be performed instead -:
- IgA levels to quantify IgA deficiency
- IgG tissue transglutaminase antibody
- IgG endomysial antibody (EMA) test
Intestinal Biopsy
This test involves a gastroscopy and biopsy of the duodenum, the first part of the small intestine. It is a definitive test for coeliac disease as long as sufficient gluten is being eaten as part of the diet. The biopsy and blood tests will be normal in a person with coeliac disease if they are sticking to a gluten free diet. A repeat biopsy to check whether the gut lining has healed is not necessary in most cases.
