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Anti-TTG (Tissue Transglutaminase)

Anti-tTG: coeliac disease in adulthood and the route to diagnosis

Q: Can coeliac disease first appear later in life?

Yes, according to Thuisarts coeliac disease, the condition an anti-tTG test is requested for, can start at any age, and according to Thuisarts the symptoms can also start at any age.

According to the NVKC, in coeliac disease, in which the body does not tolerate gluten from most cereals, the immune system makes anti-tTG: antibodies against the body's own protein tissue transglutaminase in the gut wall. According to the NVKC, tissue transglutaminase plays a role in breaking down and absorbing nutrients in the gut.

According to Thuisarts, coeliac disease can start at any age, and according to the NVKC people with coeliac disease develop a shortage of iron and vitamins in the long run. A blood test is the only way to know whether anti-tTG is present.

Star-SHL calls anti-tTG IgA below 7.0 U/ml negative.

Doctor's Assessment Included

Anti-tTG are antibodies against tissue transglutaminase, a protein in the gut wall, which the immune system makes in coeliac disease. According to the NVKC, when anti-tTG is detected the chance of coeliac disease is high, and a bowel biopsy can establish the diagnosis with certainty.

Star-SHL calls anti-tTG IgA below 7.0 U/ml negative and above 10.0 U/ml positive; Unilabs uses below 7 kU/l and Diagnostiek voor U below 8 U/mL.
According to Thuisarts, anti-tTG testing for coeliac disease requires carrying on eating gluten, because the doctor can only investigate coeliac disease while someone still eats gluten.
Anti-tTG is measured when coeliac disease is in question, which according to Thuisarts 1 in 100 people in the Netherlands have.

Anti-TTG (Tissue Transglutaminase): what Dutch laboratories use

There is no nationally agreed reference value; this is what individual laboratories publish.

The upper limit runs from 7 u/ml at Star-shl to 8 u/ml at Diagnostiek voor U.

Reference ranges by group, in u/ml
Laboratory	Group	Reference value (u/ml)	Relative scale
Star-shl	· Everyone · a limit, not a range · IgA, negative	< 7 U/ml	7
Star-shl	· Everyone · IgA, doubtful	7–10 U/ml	7 10
Star-shl	· Everyone · a limit, not a range · IgA, positive	> 10 U/ml	10
Unilabs	· Everyone · a limit, not a range · IgA	< 7 kU/l kU/l
Diagnostiek voor U	· Everyone · a limit, not a range · IgA	< 8 U/mL	8

6.25 10.75 u/ml

Source: Star-shl

Source: Unilabs

Source: Diagnostiek voor U

Each value as the laboratory itself publishes it, retrieved in 2026.

Anti-TTG (Tissue Transglutaminase): what this test measures

Unilabs measures anti-tTG as IgA in kU/l and confirms a first result of 10 times the upper limit with a test for antibodies against endomysium (EMA).

Anti-TTG (Tissue Transglutaminase): why this value matters

Anti-tTG matters because according to Thuisarts people with coeliac disease more often than others have other immune diseases, such as type 1 diabetes or a thyroid disease.

Anti-TTG (Tissue Transglutaminase): how the blood test works

Referral: No GP referral needed. After the order we arrange the referral through ZorgDomein, within one business day; orders after 17:00 or at the weekend start on the next business day. ZorgDomein emails a barcode, and that barcode is what the draw site needs.
The draw: A blood draw from a vein in the arm, at a partner laboratory's draw site. No home kit, no finger prick.
Which test: Celiac Disease · €184,-
Where: 650+ draw sites run by independent laboratories across the Netherlands. Draw sites

Anti-TTG (Tissue Transglutaminase): how to prepare

Keep eating gluten
Required

Eat gluten every day, in more than one meal, for at least 6 weeks before the draw. If you already eat gluten-free, the test can come back falsely negative.

Water is always fine. Drink as usual beforehand, it makes the draw easier.
Take your usual medication, unless your own doctor told you otherwise.

Anti-TTG (Tissue Transglutaminase): when is testing worthwhile?

According to the NVKC, an anti-tTG test is requested to establish whether coeliac disease is the cause of the symptoms, and according to Thuisarts someone has to go on eating gluten until the hospital investigation.

Anti-TTG (Tissue Transglutaminase): symptoms of a high or low value

Low Levels

When anti-tTG is not detected in the blood, the NVKC calls the chance of coeliac disease small, but in a relative of someone with coeliac disease, Thuisarts says such a result applies only to that moment.

High Levels

According to the NVKC, a positive anti-tTG gives a high chance of coeliac disease. According to Thuisarts, the hospital investigation for coeliac disease often needs an endoscopy of the duodenum, in which the doctor takes small pieces from the inside of the gut to look at under the microscope.

Anti-TTG (Tissue Transglutaminase): causes of a low or high value

What lowers the value

Too little IgA antibody production

The anti-tTG test measures antibodies of the IgA type, and a negative result is followed by checking whether the patient can make IgA antibodies in sufficient amounts.

What raises the value

Coeliac disease

When anti-tTG is detected, it usually points to hypersensitivity to gluten (coeliac disease), and the chance of coeliac disease is then high.

Anti-TTG (Tissue Transglutaminase): lifestyle and this value

Take a positive anti-tTG to your GP. According to Thuisarts, with coeliac disease a check-up with the gastroenterologist usually follows once every 1 or 2 years, and the GP sometimes takes over the check-ups for adults who manage their coeliac disease well and no longer have symptoms.

Anti-TTG (Tissue Transglutaminase): frequently asked questions

Can coeliac disease first appear later in life?

Yes, according to Thuisarts coeliac disease, the condition an anti-tTG test is requested for, can start at any age, and according to Thuisarts the symptoms can also start at any age.

Anti-TTG (Tissue Transglutaminase): sources

Star-shl, Labbepalingen (referentiewaarden per bepaling), star-shl.nl, geraadpleegd 2026-10-01 (retrieved 2026) star-shl.nl
Unilabs, Bepalingenklapper (referentiewaarden per bepaling), bepalingenklapper.nl, geraadpleegd 2026-10-01 (retrieved 2026) bepalingenklapper.nl
Diagnostiek voor U, eLabgids (Referentiewaarden DvU), diagnostiek.getincontrol.eu, geraadpleegd 2026-10-01 (retrieved 2026) diagnostiek.getincontrol.eu
NVKC, Alles over testen: Anti-TTG, allesovertesten.nl, geraadpleegd 2026-10-16 (retrieved 2026) allesovertesten.nl