Tissue transglutaminase, IgA-antibodies
In coeliac disease, the gluten in food causes inflammation on the lining of the small intestine which, over time, damages the villi structures of the small intestine. The damage can be repaired by eliminating gluten from the person’s diet. Gluten is found in wheat, rye and barley, for example.
Coeliac disease entails hereditary predisposition and may break out in childhood or adulthood, causing a life-long disorder. About 2% of Finns have been diagnosed with coeliac disease, whereas about 10% have been diagnosed with dermatitis herpetiformis, a cutaneous manifestation of coeliac disease. In coeliac disease, the body forms antibodies against its own structures. These include transglutaminase, endomysial and gliadin peptide antibodies.
When should tTGAbA be measured?
The symptoms may be so mild or vague that it is difficult to realise they are caused by coeliac disease.
The most typical symptoms include:
- Long-term diarrhoea
- Stomach pain, bloating and flatulence
- Fluctuations in bowel movements
- Reduced speed of growth in children
- Weight loss
- Lack of nutrients: iron deficiency anaemia, vitamin D deficiency
- Lactose intolerance caused by damage to the small intestine
- Bone fragility (osteoporosis)
- Tooth enamel loss
- Memory disorders
What does a tTGAbA test measure?
IgA-class transglutaminase antibodies (tTGAbA) are the most sensitive and precise test for diagnosing coeliac disease. Some people don't have IgA antibodies at all, and in that case coeliac disease is diagnosed with test tTGAbG. In those suffering from coeliac disease, the IgA deficiency is about 10–15-fold compared to the entire population.
How to interpret the tTGAbA-test result?
Normally, the result is:
- Negative: < 7 U/ml
- At threshold range: 7–10 U/ml
- Positive: >10 U/ml
tTGAbA is the most sensitive and precise test for diagnosing coeliac disease.
Changes in the antibodies indicate aggravated or reactivated coeliac disease. A gluten-free diet alleviates or even eliminates the symptoms of those suffering from coeliac disease and normalises the antibodies, although this takes several months. After a diagnosis of coeliac disease, the antibody levels should be monitored after about 6 months and then every 1 to 2 years. The tissue transglutaminase antibody test is not suited for diagnosing coeliac disease in children under the age of 2.
What can cause elevated tTGAbA values?
High levels of tTGAbA antibodies may indicate coeliac disease.
What can cause decreased tTGAbA values?
A healthy body does not produce tTGAbA antibodies.
The most typical additional tTGAbA tests:
- Endomysial antibodies (3729 S-EMA)
- Lactose intolerance test indicates whether you suffer from a metabolic disorder (B -Lakt-D)
SYNLAB test list: Tissue transglutaminase, IgA and IgG antibodies (1885 S -tTGAbA, 1886 S -tTGAbG) https://www2.synlab.fi/laboratoriokasikirja/tutkimuskuvaukset/kudostransglutaminaasi-iga-ja-igg-vasta-aineet-1885-s-ttgaba-1886-s-ttgabg/
Terveyskirjasto health library: Coeliac disease https://www.terveyskirjasto.fi/terveyskirjasto/tk.koti?p_artikkeli=khp00011&p_hakusana=keliakia
Fasting is not required
This examination does not require fasting