What is coeliac disease?

Coeliac disease (pronounced SEE-lee-ak) is an autoimmune disease that affects the small bowel. If you have coeliac disease and eat foods that contain gluten — even tiny amounts — your body responds by attacking itself, damaging your small bowel. Gluten is a protein found in grains such as wheat (including spelt), rye, barley and oats.

Coeliac disease affects people of all ages and genders. It runs in families and can develop at any age from infancy to adulthood. Currently, the only available treatment is maintaining a strict, lifelong gluten-free diet.

Early diagnosis and treatment of coeliac disease significantly reduces the risk of most complications.

What causes coeliac disease?

If you have coeliac disease, your immune system's response to gluten causes damage to the small intestine. The tiny, finger-like projections lining the bowel, called villi, become inflamed and flattened (known as villous atrophy). This reduces the available surface area of the bowel to absorb nutrients from food.

It's not yet known why people develop coeliac disease, but there are factors that can increase your risk.

If you are diagnosed with coeliac disease, you should tell family who share your genes (parents and siblings) so they can also be tested. An immediate family member (parent, sibling or child) of someone with coeliac disease has a 1 in 10 chance of developing it too.

Having certain genes (known as HLA-DQ2 and HLA-DQ8) makes if more likely that you will develop coeliac disease. However, not everyone with one or both of these genes ends up developing coeliac disease. This means that both a person's genes and their environment are likely to play a role.

You're also more likely to develop coeliac disease if you have certain health conditions including:

• type 1 diabetes
• ulcerative colitis
• neurological disorders such as epilepsy
• thyroid disease
• Down syndrome

What are the symptoms of coeliac disease?

People with coeliac disease may have severe symptoms, or they may have no obvious symptoms at all.

Common symptoms that affect the gastrointestinal tract (gut) include:

• diarrhoea or constipation
• pale stools with an unpleasant smell that are difficult to flush
• nausea and vomiting
• flatulence (passing wind) and bloating
• abdominal pain or discomfort

Other symptoms and problems can include:

• low weight or slow weight gain in children
• fatigue
• weight loss
• severe or persistent mouth ulcers
• irritability and depression
• developmental delay or delayed puberty in children
• unexplained iron, vitamin B12 or folate deficiencies

Many of these symptoms are common and may occur due to other conditions. However, coeliac disease is under-diagnosed, so it's important to consider it as a possible cause of your symptoms.

Up to half of people with coeliac disease don't have any symptoms, but their bowel may still be damaged by the condition.

Symptoms of coeliac disease can be different in children. Find out more about coeliac disease in children.

When should I see my doctor?

You should see your doctor if you have symptoms of coeliac disease, especially if you have a family history or risk factors.

Coeliac disease is a serious medical condition that affects people for their whole life, so it's important to get an accurate diagnosis from your doctor.

If you think you may have coeliac disease, don't stop eating foods containing gluten until you've been officially diagnosed, as this can interfere with the tests needed for diagnosis.

You should also ask your doctor about being tested for coeliac disease if you have:

• early-onset osteoporosis
• unexplained infertility
• a family history of coeliac disease
• liver disease
• Down syndrome or Turner syndrome
• dermatitis herpetiformis (a skin condition linked with coeliac disease)
• autoimmune disease such as type 1 diabetes or thyroid problems
• unexplained neurological (nerve) symptoms

How is coeliac disease diagnosed?

Your doctor will ask about your symptoms and perform a physical examination. If your doctor suspects coeliac disease, they may refer you for tests such as:

• Blood tests — These include testing for antibodies to gluten in your blood (known as coeliac serology). This is a screening test only. If you have a positive blood test, your doctor will confirm the diagnosis with a small bowel biopsy. If you have been diagnosed with coeliac disease and started a gluten-free diet, these antibody levels can also be used to check that your condition is improving.
• Gastroscopy with small bowel biopsy — This is essential to confirm a diagnosis of coeliac disease,
• Genetic tests — If the diagnosis is uncertain, your doctor may refer you for genetic testing. A negative genetic test can be used to rule out coeliac disease but can't confirm a diagnosis.

Beware of alternative diagnostic methods such as hair analysis, stool-based tests, iridology or Vega testing. These tests are unreliable, may delay diagnosis or give you an incorrect diagnosis and lead to unnecessary and ineffective treatments.

How is coeliac disease managed?

Coeliac disease can't be cured, but it can be managed with a strict, lifelong gluten-free diet.

Your sensitivity to gluten will never go away. The only way your small bowel can heal — and then stay healthy — is by removing all gluten from your diet. You should follow a strict gluten-free diet, even if your symptoms are mild. Mild symptoms don't mean you have a mild disease.

You should see your doctor regularly after your diagnosis. Most people with coeliac disease have blood tests at least yearly to monitor their condition. Your doctor may also refer you for another small bowel biopsy 1 to 2 years after diagnosis to make sure that your bowel is healing.

Gluten-free diet

Maintaining a gluten-free diet involves learning new skills, including reading and interpreting food labels.

Foods can only be labelled gluten-free in Australia if they don't contain any detectable gluten, oats or malted ingredients.

Most packaged food in Australia must list ingredients from grains that contain gluten on their ingredients list. Alcoholic beverages are exempt from this labelling law. This means you will need to learn which drinks are gluten-free. For example, all regular beers contain gluten. Your state coeliac association or a dietitian can help you learn which foods are gluten-free.

You can also look for the ‘crossed grain' logo on packaged foods. This logo means the product has been reviewed and approved by Coeliac Australia and is suitable for a gluten-free diet.

Can coeliac disease be prevented?

It is not possible to prevent coeliac disease. Factors such as when you give children gluten for the first time and how long you breastfeed haven't been shown to affect a child's lifelong risk of developing coeliac disease.

However, early diagnosis and treatment can reduce the chance of experiencing complications of coeliac disease.

Complications of coeliac disease

The changes in the small bowel caused by untreated coeliac disease can lead to poor absorption of nutrients. This can cause nutritional problems such as iron-deficiency anaemia and vitamin deficiencies.

Untreated coeliac disease also increases the general level of inflammation in the body. This can increase your risk of developing inflammatory conditions in many other areas of the body, including the skin, joints, bones, liver, pancreas, thyroid and nervous system. It also increases your risk of bowel lymphoma (a type of cancer) and fertility problems.

Early diagnosis and treatment of coeliac disease significantly reduces the risk of developing most of these complications.

Resources and support

Coeliac Australia supports Australians with coeliac disease. Contact your state coeliac organisation for advice and ongoing support by calling 1300 458 836. Become a member for access to research, support, recipes and news.

Making an appointment with a dietitian who specialises in coeliac disease is also useful. They can:

• explain what a gluten-free diet involves
• plan your gluten-free diet with you
• teach you how to read food labels
• make sure you can maintain a balanced diet
• determine if you need dietary supplements

You can find an Accredited Practicing Dietitian through the Dietitians Australia website or at 1800 812 942.

Call healthdirect on 1800 022 222 at any time to speak to a registered nurse (known as NURSE-ON-CALL in Victoria) for more information and advice.