Autoimmune disease

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at December 12, 2016
StartDiseasesAutoimmune disease

The immune system protects a person from infection and disease. An autoimmune disease or autoimmune disorder is a condition in which a person's immune system attacks healthy cells or tissues in their own body. It has been estimated by the American Autoimmune Related Diseases Association (AARDA) that over 49 million Americans have some type of an autoimmune disease. 

Contents

Definition & Facts

The National Institutes of Health (NIH) estimates that there are between 80 and 120 autoimmune diseases. Examples include type 1 diabetes mellitus, autoimmune hepatitis, multiple sclerosis, rheumatoid arthritis, celiac disease, scleroderma, Graves' disease, immune thrombocytopenia purpura, and systemic lupus erythematosus (SLE).

Viruses, bacteria, and fungi are pathogens that can provoke an immune response, in which the immune system produces antibodies. These antibodies make it possible for the body to destroy harmful invaders or pathogens. Autoimmune diseases involve a process whereby the immune system mistakenly interprets the body's own tissue as harmful and thus attacks it.

Autoimmune diseases may involve attacks on specific organs or they may involve systemic attacks on multiple organs. These attacks may be perpetrated by autoantibodies or by T-cells. Much remains unknown about how these diseases develop or how best to categorize them.

Symptoms & Complaints

The symptoms of autoimmune diseases vary widely and depend on the type of autoimmune disease and the types of tissues the immune system abnormally attacks. They may cause digestive, neurological, or musculoskeletal symptoms.

Rheumatoid arthritis causes aching, inflammation, burning, and soreness of the joints. Multiple sclerosis involves an attack on the brain and spinal cord and thus results in neurological symptoms such as weakness of limbs and loss of coordination.

Celiac disease causes intense abdominal pain, vomiting, and diarrhea. Graves' disease, a disorder affecting the thyroid gland, causes bulging eyes. Type 1 diabetes involves an attack on the pancreas and causes thirst, blurred vision, and unexplained weight loss.

Causes

The underlying causes of autoimmune diseases are largely unknown. There is evidence linking autoimmune diseases to mutations of the gene that codes for human leukocyte antigen. While autoimmune diseases tend to run in families, there are a variety of environmental factors that play a role in their development. These factors include chemicals, drugs, psychological factors, hormones, and diet. Autoimmune diseases are considered a leading cause of death among women who are young or in their middle age.

Diagnosis & Tests

Unfortunately, many autoimmune diseases are diagnosed when the disease is already in its later stages. A physician will inquire about the patient's medical history, and they will also want to know if a person has a family history of autoimmune disorders when evaluating their symptoms. The diagnostic process will likely include a physical examination.

The physician may run imaging tests such as X-rays, magnetic resonance imaging (MRI scans, computed tomography (CT) scans, and positron emission tomography (PET) scans. These scans can help identify the areas where the immune system response is attacking the tissue and detect the degree of deterioration. For example, patients with multiple sclerosis will undergo scans that can identify abnormalities of the brain and spine.

Diagnostic process will involve the physician running a battery of blood tests and clinical urine tests. An erythrocyte sedimentation rate test can help detect inflammation that is characteristic of many autoimmune diseases. An antinuclear antibody test may also be run and is a blood test designed to detect the presence of rogue antibodies or autoantibodies that attack the healthy tissue.

The immunofluorescence assay is a diagnostic test utilizing a fluorescence microscope to analyze microbiological samples. It uses fluorescent dyes to target the antibodies and antigens inside cells. It shows the distribution of molecules within the sample. This test is done on small sections of tissue.

Liver function tests and kidney function tests will also be performed in many cases. The latter include tests to study the presence of creatinine in the blood or urine as well as blood urea nitrogen tests.

Treatment & Therapy

Autoimmune disorders are chronic conditions that have no known cure in most cases. Treatment for these conditions involves stopping the disease from progressing, reducing the frequency of flare-ups, and decreasing symptoms in general.

It is common for physicians to recommend dietary changes as part of the treatment process. The goal will be to remove food from their diet that could cause or increase an immune response from their body. For those with Celiac disease, this means eliminating gluten from one's diet.

People who suffer from chronic pain as a result of their condition such as those with rheumatoid arthritis may be treated with nonsteroidal anti-inflammatory drugs like ibuprofen and naproxen. Regular exercise and stress reduction may also play a role in reducing the incidences of flare-ups depending on the disease.

Treatment often involves taking corticosteroids as well as other immunosuppressive drugs. The steroids are able to suppress the immune system. Other medical interventions involve everything from hormone replacement therapy to blood transfusions, physical therapy, and more. People with type 1 diabetes require extra insulin acquired through an insulin pump.

Prevention & Prophylaxis

There is no proven method for the prevention of an autoimmune disorder except to maintain one's overall health. Proactive diagnosis and treatment of infections may help reduce the risk. Stress reduction via relaxing activities such as yoga and meditation promote good health.

Avoiding exposure to environmental toxicants, quitting smoking or never beginning in the first place, avoiding secondhand smoke, and drinking alcohol in moderation promote one's overall health and may reduce the risk of autoimmune diseases.