We look at everything you need to know about coeliac disease and how it differs from gluten intolerance.
By Dr Sian Ludman
Coeliac disease is an autoimmune reaction to gluten. Unlike gluten intolerance, the disease is a lifelong illness which causes intestinal damage, although both produce similar symptoms.
So what exactly is coeliac disease, who’s at risk of it and how is it treated? Dr Sian Ludman explains:
What is coeliac disease?
Coeliac disease, also known as gluten enteropathy or coeliac sprue, is a lifelong autoimmune reaction to consuming gluten, a protein found in wheat, barley, and rye. In coeliac disease, gluten causes the immune system to produce antibodies that attack the delicate lining of the bowel, which is responsible for absorbing nutrients and vitamins from food.
Coeliac disease is a multi-system disorder diagnosed by endoscopy with biopsy of the small intestine (bowel). It can be diagnosed at any age, and can be diagnosed in babies after weaning, when cereals containing gluten are first introduced into the diet. However, the most common age of diagnosis is currently between 40 and 60 years old.
Coeliac disease is a lifelong autoimmune reaction to consuming gluten.
The symptoms can be subtle, and you may feel unwell for some time for no reason before the diagnosis is made. If left untreated, coeliac disease can lead to anaemia, low bone density, osteoporosis and, rarely, some forms of gut cancer.
Avoiding all food that contains gluten generally results in the improvement, or even disappearance, of damage to the bowel lining. However, the damage will start again if gluten is re-introduced into the diet.
Who is at risk for coeliac disease?
It used to be thought that coeliac disease affected about 1 in 1500 people. More accurate diagnosis through blood tests has shown that the condition affects 1 per cent of people across Europe. Coeliac disease affects all ethnic groups and is common not just in Europe, but also in South Asia, the Middle East, North West and East Africa and South America.
Coeliac disease occurs in people who are genetically prone to it.
Coeliac disease is more common in women than men. Coeliac disease is associated with other conditions. People with Type 1 diabetes, and thyroid problems have an increased chance of developing coeliac disease.
The risk of coeliac disease is increased by a family history of the condition. Coeliac disease occurs in people who are genetically prone to it. If you have a parent, sibling or child with coeliac disease, you have a 10 per cent chance of also developing it. In identical twins, if one twin has coeliac disease, the chance of the other twin developing coeliac disease is more than 70 per cent.
What are the symptoms of coeliac disease?
Coeliac disease has many and varied symptoms, and symptoms in adults may be different to those in children.
Childhood symptoms of coeliac disease
In children under 2 years old, symptoms and signs of coeliac disease usually include:
- Chronic diarrhoea
- Swollen stomach
- Failure to thrive
- Arm and leg muscles may become wasted and thin
Older children may experience these coeliac symptoms:
- Failure to gain weight
- Failure to grow
- Delayed puberty
- Neurological symptoms (ADHD, headaches, learning disabilities)
Adult symptoms of coeliac disease
In adults, coeliac disease symptoms may include:
- Weight loss
- Abdominal bloating
- Acid reflux
However, adults with coeliac disease may not have any of these bowel symptoms. They may approach their doctor because of the following symptoms:
- Extreme tiredness
- Bone pain and sometimes even fractures – which are due to thinning of the bones
- Ulcers in the mouth
- A blistering, itchy skin rash mostly on the elbows and knees, called dermatitis herpetiformis
- Recurrent miscarriages
- Tingling hands and feet
- Joint pain
- Hyposplenism, or reduced functioning of the spleen
The gut symptoms seen in coeliac disease may not always be present in people with the neurological symptoms.
❗️ Make an appointment with your GP if you or your child experience any of the above symptoms of coeliac disease for longer than two weeks.
How is coeliac disease diagnosed?
Your GP will ask about your symptoms. Don’t feel embarrassed about questions on the frequency and colour of your bowel motions.
• Physical exam
Your doctor may also want to know whether you have lost weight or whether you have symptoms of anaemia (tiredness, exhaustion, pallor). The doctor may examine your abdomen, look for a blistering rash on your skin and check for mouth ulcers.
The doctor may examine your abdomen or look for a blistering rash on your skin.
• Blood tests
Blood tests are then usually requested. Your doctor will check for anaemia, testing the levels of iron, folic acid, and calcium in your blood. Another blood test detects antibodies that are often found in coeliac disease. Several antibodies are linked to the condition, but the most specific is anti-endomysial antibody. If this is present in the blood, you are very likely to have coeliac disease, but will be falsely negative if you do not have gluten in your diet at the time of the blood test.
• Endoscopy and biopsy
An endoscopy with biopsy is needed to diagnose coeliac disease. Your doctor should arrange this test at the endoscopy unit at your local hospital. Children can have endoscopy under general anaesthetic (sedation) and adults may have sedation or a local anaesthetic that numbs the throat with a spray.
What else could it be?
Diarrhoea and weight loss can be due to several other causes:
- A bowel infection caused by parasites called Giardia lamblia and Strongyloides. If your symptoms start after a tropical holiday, one of these infections may be to blame.
- Overgrowth of bacteria in the small intestine.
- Lactose (milk) intolerance (though this is rare and transient)
- Whipple’s disease (a rare disease in men that prevents nutrients and fat being absorbed).
- Intestinal lymphoma (a type of cancer).
Coeliac disease treatments
✔️ Gluten-free diet
It’s not possible to prevent coeliac disease, but a gluten-free diet can reverse damage to the small intestine. This requires considerable support and information. After diagnosis your GP should refer you for a consultation with a dietitian.
It’s important that you receive regular follow up from your healthcare team. The general recommendations are to have an annual review appointment.
We can’t prevent coeliac disease, but a gluten-free diet can reverse damage to the small intestine.
✔️ Vitamins and minerals
Another important aspect of treatment is recommending supplements for vitamins and minerals. If nutrient levels are low, you may need iron tablets, folic acid supplements, and calcium.
Treatment may include the use of steroids and other drugs that damp down the immune system. This is rare.
How to follow a gluten-free diet
The gluten-free diet involves avoiding gluten, the protein found in wheat, rye and barley.
✔️ Gluten-free foods
Many foods do not contain gluten, including:
- All fruit, salads, vegetables
- Rice, maize, quinoa, millet, buckwheat
- Pulses and lentils
- Red meat, chicken, fish, eggs, and dairy products
- Processed foods such as ready meals and soups which are made without gluten
𝗫 Foods that contain gluten
- Breakfast cereals
- Pizza bases
- Biscuits, cakes, and pastries
- Some soy sauces, mustards, and mayonnaises
- Some tinned soups, sauces, ready meals, and some processed foods
- Some crisps and similar snacks
- Chips should be avoided if cooked in the same oil as battered fish
- Beer, lager, stouts, and ales are made from grain containing gluten, but other alcoholic drinks such as wine, cider, sherry, spirits and liqueurs can be included in the gluten-free diet
Gluten-free substitutes are available from most supermarkets and pharmacies. You can also get staples such as gluten-free flour, breads and pasta on prescription from your doctor. There are excellent books available on gluten-intolerance, including general guides and recipe books.
Coeliac disease complications
Coeliac disease that does not respond to a gluten-free diet may need additional treatment. In the vast majority of cases, failure of the gut to heal is due to continued gluten in the diet.
If you have been told that your gut has not healed it is important that you see a registered dietitian who can discuss your diet in more detail. Refractory coeliac disease is a term used to describe a condition that does not respond despite following a strict gluten-free diet.
Other complications of coeliac disease are rare. They include:
➡️ Infertility in women: recurrent miscarriage is sometimes associated with coeliac disease.
➡️ Severe anaemia in pregnancy: when the bowel cannot absorb enough iron and vitamins to keep up with the demands of mother and baby.
A gluten-free diet reduces all these complications, as well as treating associated symptoms.
➡️ Intrauterine growth retardation: babies who are small for their age in the womb are more frequently born to mothers with coeliac disease.
➡️ Autoimmune diseases: thyroid disease, Type 1 diabetes and some types of liver disease such as primary biliary cirrhosis.
➡️ Osteoporosis: thinning of the bones
➡️ Some cancers: sufferers have a slightly increased risk of developing bowel cancer, intestinal lymphoma and cancer of the oesophagus
A gluten-free diet reduces all these complications, as well as treating associated symptoms and conditions such as diarrhoea, mouth ulcers and dermatitis herpetiformis. Studies have shown that sticking to a gluten-free diet for five years or more reduces the risk of all cancers associated with coeliac disease to that of the general population.
Is there a cure for coeliac disease?
A gluten-free diet should enable the lining of the bowel to return to normal in most people. But damage will return as soon as you start eating gluten again.
This means the disease can be ‘cured’, but only by avoiding foods that contain gluten. If you do this, you can enjoy a good quality of life without symptoms or long-term complications.