Complete Coeliac Blood Test

Coeliac disease is a lifelong autoimmune disease caused by a sensitivity to gluten. It can come on at any age, but most people are diagnosed in adulthood. It affects approximately 1 in 100 people. Coeliac disease can take many years to diagnose because its symptoms are so common and shared with other conditions such as IBS. Symptoms of coeliac disease can include digestive problems such as bloating, wind, diarrhoea, nausea, weight loss and fatigue. There is no cure for coeliac disease, but the symptoms can be avoided by adopting a gluten free diet. 

Getting a diagnosis of coeliac disease is difficult as there is no single indicator which can be relied upon on its own. Coeliac disease is associated with a variety of autoantibodies, including tissue transglutaminase (tTG), deamidated gliadin antibodies and endomysial autoantibodies, none of which gives a reliable diagnosis in isolation. Often the testing process can last weeks as one test follows another. For those with coeliac disease, who must eat gluten for 6 weeks before each test, this can mean a long period of pain and discomfort. 

The Complete Coeliac Blood Test offers an alternative approach to testing with the aim of giving you a result you can be confident in without the need for repeat sample collection or long wait times. It involves 3 different pathways depending on the initial test results of a tissue transglutaminase (tTG IgA) and a total immunoglobulin A test as follows:

1. tTG IgA result normal: a normal result means that you are very unlikely to have coeliac disease and that you should look for other ways to manage your symptoms. The laboratory will not automatically perform any further tests.

2. tTG IgA and total IgA result very low or undetectable: Some people with a common immunological deficiency (selective IgA deficiency) will not have elevated levels of IgA antibodies in their blood even though they do have coeliac disease (a false negative result). This is especially common in people with coeliac disease. As many as 1 in 50 people with coeliac disease are also affected by selective IgA deficiency. If you have a very low tTG result, the laboratory will automatically perform a de-amidated gliadin IgG antibody test in order to confirm coeliac disease.

3. tTG IgA result high: if you have a high tTG IgA result the laboratory will automatically perform an endomysial IgA antibody test to confirm coeliac disease.

The Complete Coeliac Blood Test is a reliable way of finding out whether you have coeliac disease so that you can take steps to manage your condition.

Ask the doctor FAQs

 

Q. Why don’t we just use a test which checks only tissue transglutaminase and endomysial antibodies?

 

A. IgA deficiency is more common in people with coeliac disease (2-2.5%). This group could easily be missed if the profile did not also include a test for IgA antibodies.  A false negative result can lead to a continuation of symptoms as people who are missed but actually have coeliac disease don’t take the necessary steps to eliminate gluten from their diets.

 

Q. Why do I have to eat gluten for 6 weeks before the test?

 

The test is looking for a response to gluten which unfortunately won’t show up if you don’t eat gluten for more than 1 meal a day for at least 6 weeks. We realise that this can cause a lot of discomfort, but the benefit of this test pathway over testing a single marker at a time is that you will have all the blood tests you need for your doctor to make a diagnosis. You should not have to repeat the process again.

 

Q. Will this test provide a complete diagnosis for coeliac disease?

 

A. Some GPs may want to refer you to a gastroenterologist for you to have an endoscopy and  biopsy (where a small tissue sample is collected from the stomach wall) in order to definitively confirm coeliac disease. However, many health authorities are becoming increasingly comfortable that they can rely in this testing pathway alone, without the need for an invasive procedure.

 

Q. Is there any treatment for coeliac disease?

 

A. The only treatment for coeliac disease is the complete elimination of gluten from the diet. There is no cure for coeliac disease, but the condition and its symptoms can be managed through an exclusion diet.

 

Q Why do I need a diagnosis for coeliac disease if I can manage my symptoms myself?

 

A . Coeliac disease a life-long medical condition which needs careful monitoring for associated conditions and complications. Coeliac disease is an autoimmune disease which raises the risk of another autoimmune conditions like type 1 diabetes or thyroid disease. It can also lead to problems absorbing vitamins and minerals which raise the risk of osteoporosis and nutritional deficiencies. Most people with diagnosed coeliac disease live long, healthy lives, but regular monitoring by your GP or gastroenterologist can make sure that issues are picked up and rectified early.