Coeliac disease and gluten sensitivity — what is the difference?

How coeliac disease differs from gluten sensitivity

Coeliac disease is autoimmune in nature. In it, gluten triggers an inflammatory reaction leading to atrophy of the intestinal villi, which is why it requires a strict, permanent gluten-free diet. Left untreated, it carries a risk of osteoporosis, mental health disorders, fertility problems and small bowel lymphoma.

Non-coeliac gluten sensitivity (NCGS) is neither autoimmune nor allergic in nature and does not damage the intestine. The diagnosis was defined for patients in whom tests had ruled out coeliac disease and wheat allergy, yet gluten still caused symptoms. The diet here may be less restrictive, and the sensitivity can change over time — whereas coeliac disease is lifelong.

Symptoms

Both conditions cause similar symptoms, appearing from a few minutes to a few hours after eating products containing gluten. The most common are:

• bloating
• abdominal pain
• headache
• constipation
• diarrhoea
• nausea
• fatigue

Symptoms outside the gut can be misleading: bone and joint pain, skin changes, sensory disturbances or mouth ulcers lead patients to look for the cause with doctors of other specialties.

In gluten sensitivity the complaints usually last from a few hours to a few weeks; in coeliac disease they may last longer. Observation alone, however, is not enough for a diagnosis — tests are needed.

Diagnosis

Gluten should not be removed from the diet before testing — withdrawing it on your own affects the reliability of the results.

Diagnosing coeliac disease

The gastroenterologist orders serological tests, that is measurement of EmA, tTG, DGP or GAF antibodies in the serum, and a small bowel biopsy, which shows whether atrophy of the villi has occurred. Genetic testing for the HLA-DQ2 and HLA-DQ8 antigens is also performed. Their presence alone does not mean disease — it indicates predisposition.

Diagnosing gluten sensitivity

There is no specific marker for this condition, so it is diagnosed by ruling out coeliac disease and wheat allergy. Confirmation may come from a provocation test, carried out under medical supervision after a period on a gluten-free diet: a return of symptoms after gluten is given supports the diagnosis.