Celiac disease (also spelt coeliac disease) is an autoimmune disease. But what is an autoimmune disease and what other disorders are in this group?
Broadly speaking an autoimmune disease is caused when a person's immune system produces an inappropriate response where it mistakenly attacks the body's own cells, tissues and/or organs, resulting in inflammation and damage to otherwise healthy tissue. There are a broad range of related diseases which can be described under this label. In fact there are at least 80 different autoimmune disorders ranging in severity from mild to disabling, depending on which system of the body is under attack and to what degree. Autoimmune disorders can affect nearly every organ and system of the body. There is generally no cure, but the symptoms of these various disorders can be managed.
Autoimmune diseases affect many more people than cancer and heart disease, but yet they still remain a mystery to the medical profession. Diseases such as celiac disease, rheumatoid arthritis, lupus erythematosus (LE), multiple sclerosis (MS), inflammatory bowel disease, rheumatic fever and even the problematic skin condition of psoriasis are just some of the autoimmune diseases which affect a multitude of the population. And of course, the people reading this blog will be all too familiar with the autoimmune disease which affects their ability to consume gluten, celiac disease.
Autoimmune disorders are broadly grouped into two categories. 'Organ-specific' where one organ is affected, and 'non-organ-specific' disorders where multiple organs or systems may be affected. Some of the major types of autoimmune disease are:
Celiac disease – affects the small intestine. Symptoms include weight loss, nutrient deficiency, abdominal pain and failure to thrive.
Type I Diabetes - affects the pancreas. Symptoms include thirst, frequent urination, weight loss and an increased susceptibility to infection.
Graves' disease - affects the thyroid gland. Symptoms include weight loss, elevated heart rate, anxiety and diarrhoea.
Inflammatory bowel disease - includes ulcerative colitis and possibly, Crohn's disease. Symptoms include diarrhoea and abdominal pain.
Multiple sclerosis - affects the nervous system. Depending on which part of the nervous system is affected, symptoms can include numbness, paralysis and vision impairment.
Psoriasis - affects the skin. Features include the development of thick, reddened skin scales.
Rheumatoid arthritis - affects the joints. Symptoms include swollen and deformed joints. The eyes, lungs and heart may also be targeted.
Scleroderma - affects the skin and other structures, causing the formation of scar tissue. Features include thickening of the skin, skin ulcers and stiff joints.
Systemic lupus erythematosus - affects connective tissue and can strike any organ system of the body. Symptoms include joint inflammation, fever, weight loss and a characteristic facial rash.
What does a healthy immune system do?
Before you can understand what and autoimmune disease is you need to understand what a healthy immune system does, what it is designed to do. The immune system is the most amazing and complex system of cells, antibodies and other chemicals designed to keep you healthy and well. It is designed to recognise and attack foreign invaders such as bacteria, viruses and even rogue body cells which could turn into cancer cells. Special immune cells are constantly scanning your body to ensure it keeps these invaders out.
Your immune system is an army of soldiers and weapons inside your body which go into action each time an invader, such as a tasty tummy bug enters your body. Each soldier has a specific job to do and is programmed to attack only a specific type of bug. This is because there are so many invaders to monitor that each soldier has to be focussed on its own target. When it detects the target the soldier multiplies and heads into battle with the intention to root out the enemy and destroy it.
The soldiers of our immune system are immune cells and the weapons are a variety of chemicals such as antibodies which are produced by the immune cells to inhibit and/or destroy the invaders
The first phase in the fight against infection certain immune cells, called phagocytes and macrophages, ingest and kill the enemy. You can see the result of this immune response when you have an infected wound which becomes pus-filled, such as with a boil.
Other immune cells called T lymphocytes (T cells) use special receptors on their surfaces to identify foreign microbes, such as bacteria and viruses. They then present these invaders to the immune system and the fight begins. When the immune system is exposed to a foreign invader, either through natural infection or through immunisation programmes, B lymphocytes produce specific antibodies against that specific enemy. This is called humoral immunity. Other cells turn into killer cells to eradicate the enemy. This is called cell-mediated immunity.
When the fight is over some of the T lymphocytes turn into memory cells so that the next time that specific invader enters our body it can quickly raise the immune response and eradicate the invader before it has a chance to establish and infection.
So why do autoimmune diseases occur?
Your immune system can usually tell the difference between your normal body cells and the foreign invaders. But sometimes it go horribly wrong and gets the message muddled and starts targeting normal healthy cells by mistake. This results in chronic inflammation to organ damage which is not so good.
Normally rogue T cells that target the normal tissues of the body are destroyed by the thymus, an organ of the immune system located behind the breastbone. Unfortunately, in some people, these 'self-attacking' T cells escape destruction and can then be activated by a trigger. The exact triggers are unknown, but viral infections and hormones are among the suspects. The rogue T cells then instruct B lymphocytes (B cells) to make antibodies against the particular tissue, organ or system. Such antibodies are called 'autoantibodies'.
But the reason why this happens is not clearly understood. Many autoimmune related conditions appear spontaneously and there is not a clear trigger. Whereas others such as rheumatic fever and celiac disease have a very clear trigger.
Rheumatic fever, for example, occurs when a person (usually a child) develops Strep throat infection. As the untreated child is recovering from the Strep throat (about 2-3 weeks later) their immune system forms antibodies against the Strep bacteria to kill it and prevent it from invading again. Unfortunately, however, these same antibodies can also attack the muscles of the heart in some people which causes rheumatic fever. Sometimes these Strep antibodies attack the kidneys and cause glomerular nephritis.
And those of you reading this blog will be well aware of the role gluten has in triggering celiac disease.
So how does gluten act as a trigger in provoking an autoimmune response?
A recent study in The Lancet found that gluten could stimulate the production of a chemical called zonulin. Zonulin controls what can enter the intestinal tract by opening up the spaces between the cells of the intestinal lining. Its role is to let good nutrients in and keep larger food molecules (such as gluten) and foreign invaders out.
However, when leaky gut is present, the spaces between the cells open up too much allowing larger protein molecules such as gluten to get into the bloodstream where an immunologic reaction can take place. This has led to the theory that the overproduction of zonulin may allow the absorption of gluten to occur, and this, in turn, leads to autoimmune antibodies to form against a gluten/cellular complex. This is because the immune system thinks the larger protein molecules are foreign invaders and mount an immune response leading to food sensitivities and/or celiac disease.
In addition, this immune activation leads to more damage to the intestinal cells and the gut becomes more inflamed and more permeable or "leaky". As the damage continues, the microvilli that line the intestines and absorb nutrients become damaged, leading to other nutrient deficiencies.
Other causes of increased Zonulin production leading to leaky gut syndrome are an overgrowth of harmful organisms, like bacteria or yeast in the intestine, as well as parasite infections.
What are the risk factors for an autoimmune disease?
For many of the autoimmune diseases, women are more susceptible than men, particularly during their childbearing years. It is thought that sex hormones may be at least partly responsible. There is generally no cure, but the symptoms of autoimmune disorders can be managed. The exact causes of most autoimmune disorders are not known but the risk factors seem to include:
Genetics - a tendency to develop autoimmune disorders seems to run in families. However, family members can be affected by different disorders; for example, one person may have diabetes while another has rheumatoid arthritis. It seems that genetic susceptibility alone is not enough to trigger an autoimmune reaction, and other factors must contribute. If your first-degree relative (sibling or parent) has an autoimmune disease you are more likely to develop one too
Environmental factors - a family's susceptibility to developing autoimmune disorders may be linked to environmental factors which make work together with genetic factors. Factors such as infection, smoking, toxins in food, UV light and pollution may act as a trigger to activate the autoimmune disease in a genetically susceptible person. But what pulls the actual trigger is still a mystery.
Chronic stress – can affect the body's inflammation regulator and because inflammation plays a role in the development of autoimmune disorders, stress may be considered a trigger.
Gender – about 75% of people with autoimmune disorders are women
Sex hormones - autoimmune disorders tend to strike when a woman is in her childbearing years. It is thought that the female sex organs can increase the production of autoantibodies. Some disorders may also change – sometimes for better sometimes for or worse, by major hormonal changes such as pregnancy, childbirth and menopause.
Infection – some autoimmune disorders may be caused, triggered or worsened by particular infections. For example, rheumatic fever as described above. There is also a theory that celiac disease is caused by a previous rotavirus infection. My daughter who has celiac disease had a severe rotavirus infection which required hospitalisation when she was two. When she was 17 she developed a severe case of whooping cough (despite being immunised when she was young) I firmly believe that the rotavirus was the cause of her celiac disease and the whooping cough was the trigger.
How could rotavirus cause celiac disease?
Viruses have 2 phases of growth related to infections, latent and lytic, and it is easiest explained with cold sores caused by the herpes virus. When the virus is in the lytic phase the sufferer has an active infection and develops a cold sore on the lips or other areas of the face. In this phase, the virus is actively multiplying and is highly infectious. When the virus is in the latent phase it lives within the nerve cells and becomes part of the cell reproducing with the genetic material of the host cell. Does the latent existence of the rotavirus genetic material within the gut cells target it as being foreign by the immune system and the antibodies against gluten attack the cell as foreign?
Diagnosis of autoimmune disease
It can be hard to diagnose an autoimmune disorder, especially in its earlier stages and if multiple organs or systems are involved. Depending on the disorder, diagnosis methods may include physical examination, medical history, blood tests, biopsy and x-rays. Blood tests depend on the symptoms but include testing for autoantibodies and specific antibodies (celiac) and raised levels of chemicals like high sugar levels (diabetes) or nutritional defects (celiac. A person may have more than autoimmune disease at one time. For example, it is common for a person to have both celiac disease and diabetes type I.
It is interesting to note that often there is a significant lag time between the development of autoimmune antibodies and the onset of disease. Autoantibodies can exist for years in some people before they begin to develop symptoms. Some people may never develop symptoms.
Treatment for autoimmune disease
Autoimmune disorders, in general, cannot be cured, but the condition can be controlled and managed to reduce the symptoms. Treatments plans include:
Dietary Control - e.g. a gluten free diet for celiacs, reduced sugar diet for diabetes. Some studies have linked too much salt and high kilojoule food to more rapid development of autoimmune disease so those at risk should work on their diets.
Anti-inflammatory drugs - to reduce inflammation and pain
Corticosteroids - to reduce inflammation. They are sometimes used to treat an acute flare of symptoms
Pain-killing medication - such as paracetamol and codeine
Immunosuppressant drugs - to inhibit the activity of the immune system
Physical therapy - to encourage mobility
Treatment for the deficiency - for example, insulin injections in the case of diabetes, iron injects for celiac disease
Surgery - for example, to treat bowel blockage in the case of Crohn's disease
Other than a gluten free diet for celiac disease and a reduced sugar intake for diabetes, there is no compelling evidence that diet or exercise has a significant effect on the symptoms caused by an autoimmune disease. Obviously choosing a healthier lifestyle has health benefits overall and will make you feel better. For example, if an arthritis sufferer loses 20 kg their joints will benefit from having to carry less weight about. It is also good to avoid inflammatory foods and eat more foods with anti-inflammatory properties.
Foods which are considered to be inflammatory foods include things like farmed seafood, fast foods, foods with a high GI, processed dressings, saturated fats, soft drinks, white bread and white rice.
Foods with anti-inflammatory properties include avocado, balsamic vinegar, broccoli, cabbage, cinnamon, dark chocolate, flax seeds, garlic, ginger, green tea, legumes, mushrooms, olive oil, onions, red sweet potato and strawberries.
Science is still in the dark about so much concerning autoimmune disease. Most have only been described in the past 50 years and the difficulty is that unlike infectious diseases the cause cannot be pinpointed. The exact cause of an autoimmune disease is often unknown. Because there are few specific diagnostic tests, diagnosis of many of these disorders is delayed and there is often confusion over exactly what the patient has. There is an urgent need for more research so the answers to the many questions can be found.
