A short guide to coeliac disease

We are often told to watch what we eat, but this couldn’t be more important for patients with coeliac disease. This lifelong illness can cause problems when certain foods trigger the body’s own immune system to attack the lining of the gut. If left undiagnosed and untreated, this can lead to serious consequences. We talked to top gastroenterologist Dr Stuart Bloom, who answered our questions about coeliac disease.

What is coeliac disease?

Coeliac disease is an immune intolerance to one of the proteins in wheat called gliadin peptide – a component of gluten. It can be confused with wheat intolerance, which is much more common, but while wheat intolerance is one of many food sensitivities (others might be to dairy, eggs, etc.), coeliac disease involves a very specific autoimmune response to one particular protein in wheat.

What is gluten?

Gluten is one of many proteins that are found in wheat and the many foods made from it, including bread. Its elastic properties are what help dough to rise and keep its final shape when baking. There’s a particular region of the protein called gliadin which seems to be responsible for causing coeliac disease.

What causes coeliac disease?

We don’t know exactly how gliadin causes inflammation, but there is a genetic link; we know some of the genetic mutations and it is also more common in some populations, especially Celts and southern Irish.

How common is coeliac?

It used to be thought that coeliac disease was rare, but studies from several countries – mainly on young people – show that the incidence of the antibody that characterises coeliac disease is about one in 300 people. The number of men and women affected is about equal.

What are the symptoms of coeliac disease?

The symptoms of full-blown coeliac are:

• Diarrhoea
• Weight loss
• Abdominal distension (bloating)
• Malabsorption

However, sometimes the presentation is more insidious, with chronic fatigue, abdominal discomfort, and iron deficiency on blood testing. Coeliac can also cause an itchy skin rash over buttocks and elbows called dermatitis herpetiformis (DH). Coeliac can also be associated with other autoimmune diseases like type 1 diabetes and thyroid disease.

What foods should you avoid if you are coeliac?

The classic diet for coeliac patients is a gluten-free diet, which involves avoiding all food containing gluten. These include:

• Bread
• Pasta made from wheat
• Many other foods containing wheat products.

A full list is available from coeliac UK.

The proteins of rice and corn are different from the proteins in gluten and are made up of differently-arranged amino acids. They do not cause inflammation in patients with coeliac disease. The most recent studies suggest that oats do not promote inflammation in patients with coeliac or that only large quantities of oats can do so. One concern with oat flour (and possibly oat bran) is that there may be contamination with wheat, rye, or barley during the process of milling.

How is coeliac disease managed?

The diagnosis of coeliac disease usually involves some blood tests and a camera test (endoscopy) of the stomach. This is done so that we can get biopsies of the upper part of the intestine (the duodenum). These biopsies show damage to the duodenum in untreated coeliac disease, which improves more-or-less to normal with a gluten-free diet.

Subsequent management of coeliac disease involves regular monitoring of blood tests, checking adherence to a gluten-free diet, and sometimes other tests; for instance, we might assess bone density, because coeliac patients are more susceptible to osteoporosis.

Can you get complications from coeliac disease?

Most people do well on a gluten-free diet, although the disease involves life-long avoidance of gluten. Very rarely, if the disease remains active (usually because the diet is not kept to), then there can be some problems with uncontrolled inflammation of the bowel, which can require a more active treatment. There is a small incidence of a type of intestinal cancer called lymphoma, associated with poor control of coeliac disease.

Does coeliac disease involve any drug treatment?

A few people do not respond to a gluten-free diet, in which case steroids or an immunosuppressant may be needed.

If you have noticed any of the gastrointestinal symptoms mentioned in this article, consult your doctor or a specialist.