Coeliac disease blood test (antibodies)

Coeliac disease blood test with IgA tissue transglutaminase antibodies, IgA endomysial antibodies and total IgA. It is the initial assessment for coeliac disease when there are symptoms, iron deficiency anaemia or a family history. For the result to be reliable, you must keep eating gluten as normal before the sample is taken.

No prescription or appointment needed

Results in 3-5 working days

Includes: Tissue transglutaminase antibodies IgA · Endomysial antibodies IgA · Total IgA. See what each one measures

What it is for

It is used to investigate whether there are antibodies compatible with coeliac disease. It can help with persistent diarrhoea, bloating or abdominal pain, but also when the disease shows itself outside the digestive system, for example with iron deficiency anaemia, weight loss or nutritional abnormalities.

Serology is the first step, not always the last. A positive result must be assessed by a doctor and, depending on age and context, may require a biopsy or other checks before gluten is cut out for good.

When it is recommended

Persistent diarrhoea, bloating or abdominal pain
Iron deficiency anaemia without a clear cause
Unexplained weight loss or nutritional deficiencies
A first-degree relative with coeliac disease
Dermatitis herpetiformis
Type 1 diabetes, autoimmune thyroiditis or other conditions linked to a higher risk of coeliac disease

Clinical comment

We have included total IgA because the transglutaminase and endomysial antibodies in this profile are IgA type. In a person with IgA deficiency, both can come back negative even when coeliac disease is present. In that case, antibodies of another type and a specific assessment are required.

The second important condition is to keep eating gluten. When it is cut out, the antibodies can fall or disappear and serology is no longer reliable. Bear in mind that it is not advisable to start a gluten-free diet on suspicion alone, nor to reintroduce gluten on your own if it has already been cut out: the amount and the length of exposure should be decided with a professional.

Conventional antigliadin antibodies are not included because they perform less well than current tests. A negative result makes coeliac disease less likely, but does not exclude it in every scenario, especially if little gluten has been eaten, there is IgA deficiency or clinical suspicion is high.

Dr. Antonio Mas

What is tested

Tissue transglutaminase antibodies IgA: The most widely used initial serological test for investigating coeliac disease.
Endomysial antibodies IgA: They have high specificity and help confirm that a positive serology is compatible with coeliac disease.
Total IgA: Checks for IgA deficiency, which could make the two antibodies above come back falsely negative.

How to prepare

No fasting is required. You must have been eating gluten as normal during the preceding weeks. If you already follow a gluten-free diet, seek advice before having the blood test, because a negative result might not be valid.

You can add

Without another needle. It is offered when you order, so you do not have to decide now.

General blood testA general blood test with full blood count, glucose, cholesterol and kidney and liver function: the basic parameters included in any general check-up.+€59.00
General + nutritional blood testEverything in the general blood test (anaemia, kidneys, liver, cholesterol and glucose) plus iron stores, vitamin D, vitamin B12 and folic acid. It is the broadest add-on: it covers the general and the nutritional in one go.+€129.00
Iron and anaemia studiesDistinguishes between iron deficiency, anaemia and vitamin B12 or folic acid deficiency, which call for different approaches.+€49.00

Related blood tests

We have other profiles in Digestive with more or fewer tests:

The most comprehensive is not always the most useful. Each profile page explains when it makes sense and when it does not.

What it is based on

Rubio-Tapia A, Hill ID, Semrad C, et al. · American Journal of Gastroenterology 118(1):59-76
American College of Gastroenterology Guidelines Update: Diagnosis and Management of Celiac Disease
Recommends IgA tissue transglutaminase antibodies as the first test for coeliac disease and measuring total IgA in the same sample, because people with IgA deficiency do not produce those antibodies and the result comes back falsely negative. It also makes clear that serology is only valid while gluten is still being eaten as normal.

Protocol designed by Dr. Antonio Mas, specialist in Endocrinology and Nutrition, Spanish medical licence no. 080846289, and reviewed in September 2026.

This blood test is a standardised protocol and does not replace a medical consultation. If you have symptoms, a known condition or a complex clinical situation, speak to your doctor.