Coeliac Disease

What is Coeliac Disease?

Coeliac disease is an autoimmune disorder that affects the small intestine. People with coeliac disease experience an adverse reaction to gluten, a protein found in wheat, barley, and rye. This reaction causes damage to the lining of the small intestine, leading to the malabsorption of nutrients.

The body produces antibodies against gluten, which can cause gastrointestinal symptoms. Coeliac disease is a lifelong disorder. 

Coeliac Disease's Impact on Anatomy and Health

The small intestine's lining is covered in tiny finger-like projections called villi. In people with coeliac disease, gluten triggers an immune response that damages the villi, leading to inflammation, swelling, and even destruction.

Types of Coeliac Disease

There are three main types of coeliac disease based on the symptoms experienced.

• Classical coeliac disease is the most common form of coeliac disease and is typically diagnosed in childhood. People with classical coeliac disease have primarily gastrointestinal symptoms, including diarrhoea, bloating, and abdominal pain.
• Non-classical coeliac disease is often diagnosed later in life and can present with symptoms, including anaemia, fatigue, and infertility. People with non-classical coeliac disease may have few or no gastrointestinal symptoms.
• Asymptomatic (Silent) coeliac disease presents itself without any signs or minor bowel issues. The patient experiences edema (oedema), joint pain and migraines.

Who Does Coeliac Disease Affect?

Coeliac disease affects 1 in every 100-300 individuals. It can appear at any age, with peaks in childhood and for adults above 50. 

Coeliac disease can affect anyone, but it is more common in specific populations. People who are most at risk for coeliac disease include:

• Family members of people with coeliac disease
• People with other autoimmune disorders, such as type 1 diabetes or thyroid disease
• People with Down syndrome or Turner syndrome
• People with a family history of coeliac disease

How Does Coeliac Disease Occur?

Coeliac disease occurs when the body’s immune system abnormally responds to the gluten protein in everyday food items. 

The body’s T-cells attack the small intestine cells, causing inflammation and causing the loss of your microscopic intestinal tentacles (villi). These hair-like projections or villi absorb all the nutrients and vitamins from the food. 

Villous atrophy is what causes Coeliac disease symptoms. This damage to the intestines also leads to fatigue. 

Causes of Coeliac Disease

The exact cause of coeliac disease is unknown, but it is believed to be a combination of genetic and environmental factors. Some of the factors that may contribute to the development of coeliac disease include:

• Genetics - Coeliac disease tends to run in families, and specific genetic markers are associated with an increased risk of developing the condition.
• Gluten - Gluten is a key trigger for the immune response that causes damage to the small intestine in people with coeliac disease.
• Other environmental factors - Other factors, such as infections, gut bacteria, and even stress, may contribute to the development of coeliac disease.

Symptoms of Coeliac Disease

The symptoms of coeliac disease can occur on their own or appear with symptoms of another disorder. 

They often mimic the signs of Irritable Bowel Syndrome (IBS). The patient may complain of: 

• Abdominal pain and bloating
• Diarrhoea or constipation
• Nausea and vomiting
• Fatigue and weakness
• Anaemia
• Weight loss or weight gain
• Depression and anxiety
• Skin rash or dermatitis herpetiformis
• Joint pain
• Headaches
• Abnormal liver tests
• Miscarriage 

Stages of Coeliac Disease

There are no stages, but the severity of the symptoms is gradient and depends on the amount of gluten in the diet. 

The symptoms will be proportionally severe to higher ingestion of gluten-containing products.

How is Coeliac Disease Diagnosed?

Diagnosing coeliac disease can be challenging, as its symptoms may be similar to those of other conditions. To diagnose coeliac disease, doctors typically perform tests to assess symptoms and confirm the presence of antibodies and intestinal damage.

• Blood Tests: Blood tests are typically the first step in diagnosing coeliac disease. These tests can detect antibodies in the blood, including anti-tissue transglutaminase (tTG) and deaminated gliadin antibodies, produced when a person with coeliac disease consumes gluten. Elevated levels of these antibodies indicate an autoimmune response to gluten.
• Biopsy: If blood tests suggest coeliac disease, the doctor may perform a biopsy of the small intestine. During an endoscopy, a small piece of tissue from the small intestine's lining is taken and examined under a microscope for signs of damage, such as flattened or shortened villi. This test is considered the gold standard for diagnosing coeliac disease.
• Genetic Testing: Genetic testing can also diagnose or rule out coeliac disease. The test looks for the presence of specific genes associated with it. However, having these genes does not necessarily mean having coeliac disease, as many people with these genes may not develop the condition.

The disease is confirmed by performing a duodenal biopsy to observe villous changes and intestinal inflammation. 

How is Coeliac Disease Treated?

The only treatment for coeliac disease is a strict gluten-free diet. This means avoiding all foods that contain wheat, barley, and rye. Some people may also need to avoid oats. Following a gluten-free diet can be challenging, but it is essential for managing the symptoms of coeliac disease and preventing further damage to the small intestine.

In addition to a gluten-free diet, some people with coeliac disease may need vitamin and mineral supplements to address any deficiencies caused by malabsorption. If you are unsure what foods are safe or need help sticking to a gluten-free diet, speak to a dietitian specialising in coeliac disease.

Once the gluten has cleared in your system, the symptoms subside with time and eventually stop. 

Your doctor can monitor progress by re-examination and repeating lab tests. If the symptoms are severe, steroids may be prescribed to control the symptoms, and multivitamins would be given to treat malnutrition. 

What if Coeliac Disease is Untreated?

If left untreated, coeliac disease can have serious long-term consequences. Some of the potential complications of untreated coeliac disease include:

• Malnutrition: When the small intestine is damaged, the body cannot absorb essential nutrients, leading to malnutrition.
• Anaemia: Coeliac disease can cause iron deficiency anaemia, leading to fatigue, weakness, and shortness of breath.
• Osteoporosis: Untreated coeliac disease can lead to a loss of bone density and an increased risk of fractures.
• Infertility: Women with coeliac disease may have trouble getting pregnant.
• Increased risk of certain cancers: People with coeliac disease are at an increased risk of developing certain cancers, such as lymphoma.

Make sure to seek medical advice if you suspect you may have coeliac disease, as early diagnosis and management can prevent serious complications and improve quality of life.