Coeliac disease (gluten-sensitive enteropathy; coeliac sprue)

• What is Coeliac Disease (Gluten-Sensitive Enteropathy, Coeliac Sprue)
• Statistics on Coeliac Disease
• Risk Factors for Coeliac Disease
• Progression of Coeliac Disease
• Symptoms of Coeliac Disease
• Clinical Examination of Coeliac Disease
• How is Coeliac Disease diagnosed?
• Prognosis of Coeliac Disease
• How is Coeliac Disease treated?
• Coeliac Disease (Gluten-Sensitive Enteropathy, Coeliac Sprue) References

What is Coeliac Disease (Gluten-Sensitive Enteropathy, Coeliac Sprue)

Coeliac disease is a chronic inflammatory disease of the small bowel. In genetically susceptible individuals, ingestion of gluten (a protein found in wheat, barley and rye) causes injury to the lining of the small bowel, resulting in diarrhoea and malabsorption of nutrients and minerals. It usually affects the first part of the small bowel (duodenum and jejunum), but can affect the entire small bowel in some people.

Statistics on Coeliac Disease

Coeliac disease is a common condition which affects 1% of people in Western populations. It is more common among Caucasians but less common among people of African and Asian descent. In Australia, it occurs in at least 1 in 250 people. Symptoms may start at any age, ranging from infancy to adulthood. For unknown reasons, it is 2-3 times more common in women than men.

Risk Factors for Coeliac Disease

Environmental factors

It is clear that coeliac disease is associated with the ingestion of gliadin, which is a component of gluten. Gluten is present in wheat, rye, barley and, in smaller amounts, oats. A gluten free diet reverses both patient symptoms and damage to the small bowel. Exposure to other environmental antigens (e.g. a virus) may also have a role in triggering the onset of the disease. Other risk factors may include breastfeeding, when gluten ingestion commences, and smoking.

Immunological factors

People with coeliac disease have certain antibodies in the blood, such as IgA antigliadin, IgA antiendomysial, and IgA anti-tissue transglutaminase (tTG) antibodies. These antibodies are rarely seen in people without coeliac disease, but it is unknown whether these antibodies actually cause coeliac disease or are a result of the disease.

Genetic factors

Coeliac disease has a genetic component: 10% of immediate family members are likely to have the disease as well, even though they may experience no symptoms.

Almost all people with coeliac disease have certain genetic components (alleles) known as HLA-DQ2 or HLA-DQ8. However, these two alleles are also present in around 30% of the population, and most of those people do not have coeliac disease. Therefore, there may be other genes or factors that are also involved in causing coeliac disease.

Associated diseases

Coeliac disease is associated with other autoimmune diseases, including diabetes mellitus type 1, IgA deficiency, thyroid disease, primary biliary cirrhosis, Sjogren’s syndrome, and a skin condition known as dermatitis herpetiformis.

Progression of Coeliac Disease

The first symptoms of coeliac disease may appear in infancy after the introduction of cereals in the diet. Children may grow out of it during adolescence, but some experience a return of symptoms a few years later. Alternatively, the symptoms may first appear at any age from infancy through to adulthood. Many patients experience frequent attacks of disease that come and go spontaneously. Different people experience different symptoms, ranging from mild/minimal to severe, but the majority get relief after starting a gluten-free diet.

Symptoms of Coeliac Disease

In coeliac disease, some people may experience different symptoms to others. Adults usually have diarrhoea and abdominal pain or discomfort, but some may have symptoms unrelated to the bowels. The following are the main symptoms of coeliac disease:

Symptoms related to the bowels:

• Steatorrhoea / offensive stools (caused by excess fat in the stools);
• Diarrhoea;
• Abdominal pain;
• Nausea and vomiting;
• Flatulence;
• Bloating and other non specific gastrointestinal symptoms.

Other symptoms:

• Weight loss;
• Fatigue and weakness;
• Aphthous ulcers, angular stomatitis and dermatitis herpetiformis;
• Joint pain, arthritis and myalgia;
• Depression or neurological symptoms;
• Symptoms of iron-deficiency anaemia;
• Symptoms of osteomalacia.

Infants and children

Infants and young children may experience diarrhoea, distended abdomens, and poor weight gain. Vomiting, poor appetite, irritability and constipation are also common. Older children may also have short stature or anaemia.

People who are diagnosed after being screened or during biopsy for another reason may have no symptoms at all.

Clinical Examination of Coeliac Disease

During the examination, the doctor may check for signs of anaemia and malnutrition. There may be signs of iron deficiency, such as anaemia, deformed nails (koilonychia), mouth ulcers and inflammation of the tongue. Other signs include swelling due to lack of protein, and neurological problems from multiple nutrient deficiency. An itchy, blistering skin condition called dermatitis herpetiformis may be seen, especially around the elbows and scalp, and occurs almost exclusively in people with coeliac disease.

Infants and children

In children, the doctor may check for signs of anaemia, malnutrition and poor weight gain. In addition, the doctor may also do a developmental assessment to check for developmental delay. A developmental assessment is a way of assessing whether a child is developing at a normal level for his/her age. It may involve observing the child at play, getting the child to sit, stand or walk, or asking questions about the child’s behaviour and speech.

How is Coeliac Disease diagnosed?

In patients with signs and symptoms suggestive of coeliac disease, first of all the doctor might do some blood tests to determine if biopsy is necessary. These blood tests screen for coeliac disease but cannot diagnose the disease.

To confirm the diagnosis, biopsies have to be taken, which are tiny samples of the lining of the first section of the bowel (duodenum and jejunum). This is usually done under sedation by passing a tube with a camera down the throat into the stomach and the small bowel (endoscopy). It is vitally important to not start on a gluten-free diet before undergoing these tests, because they can produce false results in patients who are on a gluten-free diet.

Prognosis of Coeliac Disease

Untreated coeliac disease can result in a poorer quality of life from multiple bowel symptoms, weight loss, anaemia and general weakness. In the long term, untreated coeliac disease is associated with a higher risk of certain cancers, infertility, osteoporosis, and a small spleen.

Patients with coeliac disease are 80 times more likely to develop cancer of the small bowel compared with the general population. However, this cancer is usually extremely rare, so the absolute risk of a patient actually developing it is still very low. Other associated cancers include oesophageal squamous cell carcinoma, oropharyngeal (throat) squamous cell carcinoma, and non-Hodgkin’s lymphoma. It is thought that a gluten free diet is protective against the development of these cancers in patients with coeliac disease.

Coeliac disease is also associated with delayed onset of periods in girls, early menopause, absent menstruation, recurrent miscarriages and fewer children due to relative infertility. A gluten free diet can reduce the risks of having these conditions.

People with coeliac disease are 1.9 to 3.8 times more likely to die when compared to the normal population. This is mostly because of the increased risk of getting cancer. However, after 1-5 years on a gluten free diet, the risk returns down to normal. Hence, a gluten free diet improves quality of life and reduces the risk of dying in people with coeliac disease.

How is Coeliac Disease treated?

Diet

The mainstay of treatment for coeliac disease is complete elimination of gluten from the diet. Because it is a major, lifelong dietary change, it is important to note that this should be tried only after the diagnosis is confirmed through biopsy. The doctor may refer patients to a dietitian, who is the best person to provide important information and education about nutritional and dietary requirements in coeliac disease. They may also provide practical advice about implementing a gluten free diet.

People with coeliac disease should avoid all foods containing wheat, rye and barley, as well as gluten-containing medicines. Most patients are not affected by oats, but commercially available oats are often contaminated with gluten from wheat and other grains.

Other starchy foods such as rice, corn, maize, buckwheat, potato, soybean and tapioca are all safe for patients with coeliac disease.

For more information, see Gluten free diet.

Medication

Medications are not useful in most patients with coeliac disease. Some patients with refractory coeliac disease have had improvement with corticosteroids, azathioprine, cyclosporin or infliximab, but these areas are still being actively researched.

Screening

Coeliac disease has a genetic component, as around 10% of immediate family members are likely to have the condition as well. Hence, it is important to screen all immediate family members for coeliac disease. This usually involves a simple blood test, followed by endoscopy if the test is positive.

Support

Joining a local support group can be helpful for people with coeliac disease. A reputable coeliac association is a great resource for up-to-date information on services and support groups in the local area.

Follow-up

Maintaining a gluten-free diet can be a challenging and overwhelming process for some people. Hence it is important to have regular follow-up with a doctor or dietitian so that any problems or issues can be discussed. Some common problems encountered are:

• Inadequate education/ no dietitian referral
• Unable to read food labels due to poor vision, illiteracy or non-English speaking background
• Food not prepared by the patient
• Frequent dining out / travel
• Gluten free products are too expensive
• Other medical problems that may affect a person’s ability to understand and follow the strict diet

Often patients may be continuing to eat gluten inadvertently, as many processed foods can have gluten in them. This is a common reason for persistent symptoms after commencing a gluten free diet. Nevertheless, occasionally there may be another reason for the persistent symptoms, such as complications of coeliac disease, another diagnosis, and refractory coeliac disease. Hence, it is important to follow up with a health professional if the symptoms persist or recur after a period of remission.

Click here to view an information pamphlet on coeliac disease.

Coeliac Disease (Gluten-Sensitive Enteropathy, Coeliac Sprue) References

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4. Dubé C, Rostom A, Sy R, Cranney A, Saloojee N, Garritty C, et al. The prevalence of celiac disease in average-risk and at-risk Western European populations: A systematic review. Gastroenterology. 2005; 128(4, Suppl 1): S57-S67.
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7. Robbins SL, Fausto N, Abbas AK, Kumar V, Cotran RS. Robbins and Cotran Pathologic Basis of Disease. 7th ed. Philadelphia: Saunders; 2004.
8. Longmore JM. Oxford Handbook of Clinical Medicine. 6th ed. Oxford; New York: Oxford University Press; 2004.