COELIAC DISEASE

by Digestive Disorders Foundation

What is Coeliac Disease?

Some people are sensitive to a protein in cereals called gluten. When eaten, gluten causes changes in the lining of the upper part of the intestine which impairs its ability to absorb nutrients from food. The condition is therefore sometimes called gluten sensitive enteropathy (intestinal damage). For many years the condition has been recognised in children and called coeliac disease, though it can manifest itself at any age.

How common is it?

In Britain, the condition affects approximately one in a thousand people. It is more frequent in parts of Ireland. Its frequency is increased among family members of a person affected. The condition also occurs among people from abroad, especially from northern India. The frequency of gluten sensitivity is greater than expected among people with some other disorders, particularly those with diabetes who need insulin.

What are the symptoms?

In childhood, the condition most commonly presents between 9 months and 3 years of age after the introduction of cereals into the diet. The child loses or fails to gain weight, loses appetite, and the stools become softer, paler, larger and more frequent than usual. The tummy may appear swollen and contrasts with thin, floppy muscles. Vomiting, diarrhoea or constipation may occur.

At older ages, coeliacs tend to present with a deficiency of one or more nutrients because these are not absorbed properly. In childhood or adolescence there may be short stature and in adults, weight loss. Tiredness and irritability are common. The skin and tongue may appear pale due to lack of the normal red pigment in blood (anaemia). Problems with bones may occur, such as deformity, pain or liability to fracture. Since nutrients are incompletely absorbed, increased bowel frequency with the passage of bulky pale stools may occur and there may be associated abdominal pain and/or distension. However, many sufferers experience no bowel disturbance, and they can be constipated.

It is likely that many people with gluten sensitivity have few or no symptoms and the condition remains unrecognised unless it is looked for when a close relative is discovered to have it, or an unexpected blood test result leads to further investigation.

What investigations are needed to detect gluten sensitivity?

When gluten comes into contact with the intestinal lining of a person who is sensitive to it, changes occur which are detectable under a microscope. The characteristic change is flattening of the projections called ‘villi’, which resemble pile in a carpet though in a few people there may only be an alteration in the surface layer of cells.

The most important test is to examine a tiny snip, known as a biopsy, from the surface of the small intestine.

A flexible telescope (endoscope) is usually passed through the mouth into the stomach and upper intestine so that the lining can be inspected and a biopsy taken.

This process takes only a few minutes and is often made easier and less uncomfortable by giving a mild sedative beforehand. Alternatively, a biopsy can be obtained by swallowing a special capsule on the end of a narrow tube.

If the biopsy is abnormal, a second test may be advised after a period to check that the intestinal surface returns towards normal.

When there is doubt about a previous diagnosis, or the changes on biopsy are uncertain, another biopsy may be advised after a person deliberately takes gluten for a period (gluten challenge).

Blood tests are helpful in detecting the body’s reaction (antibodies) to gluten or as an indication of intestinal damage. Other blood tests indicate deficiencies of iron, vitamins such as folic acid, or minerals such as calcium. Inherited susceptibility can also be suggested by a blood test. Such blood tests are useful for screening relatives or to suggest that gluten sensitivity may be the cause of symptoms or nutrient deficiency. These tests do not make the diagnosis but indicate the advisability of a biopsy test.

If abdominal symptoms are troublesome or develop despite treatment, a barium X-ray of the intestine, which involves swallowing a tasteless white liquid, may be advised.

Association with a skin condition (dermatitis herpetiformis)

People with an itchy, blistering skin eruption affecting the knees, elbows, buttocks and back, called dermatitis herpetiformis, almost always also show evidence of gluten sensitivity on intestinal biopsy. A gluten-free diet is advised as treatment in addition to a drug.

What treatment is available?

The abnormality of the intestine improves or disappears if gluten is avoided in food. This means excluding all foods which contain wheat, rye or barley. There is debate as to whether oats should also be avoided. Currently most authorities advise omitting oats from a gluten free diet since some brands may contain gluten. To remove gluten from all food and drink is difficult because it is present in bread, biscuits, cakes, pastries, breakfast cereals, pasta, beer, and most soups, sauces and puddings.

Gluten-free foods, such as gluten-free flour, bread, biscuits and pasta are available on prescription by the doctor. Lists of gluten-free foods are available from manufacturers and also the Coeliac Society of the UK, PO Box 220, High Wycombe, Buckinghamshire, HP11 2HY. 01494 437 278

What help is available?

Keeping to a strict gluten-free diet requires determination. It affects meal arrangements within the family. It makes eating in restaurants and with friends difficult. Sufferers, especially adolescents, feel different from other people, and restricted in their social life.

It is therefore important to make use of all help available and a dietitian should always be consulted. The Coeliac Society is a national patient self help group offering support and encouragement to people with Coeliac Disease, offering up-dated lists of gluten free foods and information regarding gluten free diets.

How long should gluten be avoided?

The potentially harmful effect of gluten on the intestine is life-long and the diet should therefore be followed as a permanent change in life-style.

Sufferers feel so much better once they start the diet that they tend to regard themselves as cured; this is especially so for teenagers who were diagnosed while an infant. It is essential that the diagnosis should be established with certainty to begin with, and preferably confirmed by recording improvement in a second intestinal biopsy after maintaining the diet for a period of weeks or months. Only if there is doubt about the original tests should gluten be taken again as a preliminary to a further biopsy test.

What complications can occur?

Women with untreated gluten sensitivity can experience infertility which is restored by withdrawal of gluten from the diet. Before and during pregnancy, women with gluten sensitivity should be particularly careful to take a supplement of folic acid, as advised for all women.

Thinning of bones (osteoporosis) may be more common among coeliacs than in the general population.

A few people with the condition do not show the usual rapid response to exclusion of gluten and special advice may be needed. More severe damage than usual, including narrowing of the intestine, and even the development of a special form of cancer can rarely occur. These complications are very uncommon, especially if the condition is well treated.

Conclusion

Gluten sensitivity is curable by avoiding gluten in all food. The results of this treatment are excellent but it is inconvenient. A temporary or occasional lapse in the diet is unlikely to do harm but everyone with this condition should be advised to exclude gluten from their diet for the rest of their life. If they do, they should have no further trouble but they will need help and encouragement to persevere with this alteration to their life-style.