Have you ever heard of autoimmune diseases? Do you, like millions of others, make one?
The term autoimmune disease is used to describe the conditions under which the body’s immune system – which is supposed to defend the body against viruses, bacteria and other invaders – is involved in the cause or perpetuation of a disease. It is as if the organization’s defense system has activated its host.
Some examples of autoimmune diseases
Unfortunately, conditions considered autoimmune abound. Here are some typical or common examples:
Rheumatic diseases, such as
Rheumatoid arthritis – This condition causes inflammation, stiffness and pain in several joints; inflammation of other organs (such as the lungs or eyes) can also develop
Lupus – When people develop lupus, they usually develop inflammation in several parts of the body, especially the joints, skin, lung walls and kidneys.
Sjogren’s syndrome – This condition causes dry eyes and mouth due to inflammation and healing of the glands that produce tears and saliva; arthritis, lung disease and inflammation of other organs are also common.
Rheumatic polymyalgia (PMR) – People with PMR are generally over 60 years of age and have sudden pain and stiffness in the shoulders, neck and hips; it may be a “close cousin” of rheumatoid arthritis.
Ankylosing spondylitis – This disease is characterized by inflammation and stiffness of the lower spine, including the sacroilic joint; other joints are often also inflamed.
Vascularitis – This term means “inflammation of the vessels” and refers to a family of conditions in which inflammation of blood vessels causes troublesome symptoms and, in some cases, organic damage. Examples include temporal arteritis, granulomatosis with polyangiitis, and hypersensitivity vascularitis.
Multiple sclerosis – This is a condition in which the wall of axons (called myelin) is damaged by an immune attack; axons are projections of nerve cells that allow them to talk to each other. As a result, the brain and spinal cord do not function properly, resulting in problems with movement, balance, vision and others.
Celiac disease – In the case of celiac disease, the consumption of gluten causes an immune response that damages the small intestine and interferes with normal digestion. Other problems, such as rashes, joint pain and fatigue can also develop.
Type 1 diabetes – When people talk about diabetes, they usually refer to type II diabetes (in which the body becomes resistant to insulin); this type accounts for about 95% of all diabetes cases. In the case of type 1 diabetes, an immune attack damages the part of the pancreas that produces insulin, resulting in insufficient insulin to regulate blood sugar levels or the body’s use of energy. Organ damage (including kidneys and eyes), frequent urination and excessive thirst are common problems.
Alopecia areata – This is a skin disease in which an immune attack on hair follicles results in uneven hair loss, especially on the scalp.
And there are many others.
All of these diseases have in common evidence that the body’s immune system is responsible in one way or another. For example, a skin biopsy may show that immune cells congregate near an area of rash; or there may be antibodies circulating in the blood that target normal tissues. In addition, drugs that suppress parts of the immune system can be an effective treatment. However, for most of these conditions, the idea that they are autoimmune in nature is suggested by the evidence but difficult to prove; in fact, some autoimmune diseases may be due to an infection or allergic reaction, and immune abnormalities are only a reaction.
Why do autoimmune diseases develop?
The immune system is extremely complex and decades of research have shed light on some of the reasons why it is failing in autoimmune diseases. But, for most autoimmune diseases – including those mentioned above – the true cause is unknown. The most common (and fairly general) theory is that a person with a particular genetic background that makes them susceptible to having “misses” of the immune system encounters an environmental trigger (such as an infection or toxin) and triggers an autoimmune disease. In most cases, we do not know the trigger or toxin and in a particular population (or a family or even in identical twins), we do not know why some people develop these conditions and others do not. These gaps in our knowledge slow the development of effective treatments or preventive measures.
What can be done about autoimmune diseases?
Treatment depends on the condition, but most autoimmune diseases are treated with drugs that suppress or alter the immune system in the hope of weakening it sufficiently to calm the disease, but not to the point of causing side effects (including infections). In some cases, effective treatments are discovered by chance; for example, in the 1920s, injections of gold salt were first used to treat rheumatoid arthritis because gold had been used as an antibiotic to treat tuberculosis and it was thought that arthritis rheumatoid arthritis was caused by an infection. More recently, the identification of immune cells (such as the B cells that make antibodies) or chemical messages (also called cytokines, such as the tumor necrosis factor, or TNF) involved in autoimmune diseases have led to therapies targeting these components of the immune system (such as rituximab, a treatment for B cells or infliximab, an anti-TNF drug).
The end result
Autoimmune diseases are a mysterious set of conditions whose severity ranges from simple boredom to death danger. Research is ongoing and has made remarkable progress in recent years; while effective therapies are available for most of these conditions, the remedies are not.
It has long been anticipated that we will soon be able to analyze a person’s genes, assess the behavior of their immune system, measure the number and function of immune cells or chemical messengers, and collect all this information to develop a specific and individual treatment regimen that will likely be safe and effective. We are not there yet.