Signs and Symptoms of Autoimmune Disease
The primary function of the immune system is the protection of hosts from infectious agents. However, there are some diseases, called autoimmune diseases (ADs), triggered by the loss of immunological tolerance to self-antigens leading to chronic illnesses. There occurs a failure to differentiate self from non-self and the formation of autoantibodies in these illnesses. The existence of autoreactive T and B cells and a complex mechanism of multifactorial etiology forms the basis of autoimmune diseases. Genetics and environmental factors are responsible for the onset of disease. The incidence of ADs is estimated at 3–5% worldwide.
Autoimmunity, play a major role in more than 80 different diseases. Autoimmune disorders can be of different types. These may be systemic, as in the case of systemic lupus erythematosus (SLE), tissue-specific, as in the case of multiple sclerosis (against myelin) or type 1 diabetes (against pancreatic beta cells), or organ-specific such as autoimmune thyroid disease.
Autoimmune disease symptoms
- Rheumatoid arthritis: The most common clinical presentation of RA is inflammatory polyarthritis (affecting more than 5 joints). The joints most commonly involved are the hands and feet, even though any synovial joint (the joint that joins bones or cartilage with a fibrous joint capsule) is also at risk. The immune system targets the joints leading to the immobilization of fingers, wrists, feet, and ankle joints and causing pain and inflammation in these joints. If untreated, rheumatoid arthritis slowly causes permanent joint damage.
- Systemic lupus erythematosus (lupus/SLE): SLE is an autoimmune disease with multiorgan involvement. In SLE the autoimmune antibodies can attach to tissues throughout the body. The disease mostly affects joints, lungs, blood cells, nerves, and kidneys. The main symptoms include flares, skin rashes, fatigue, fevers, and pain or swelling in the joints.
- Inflammatory bowel disease (IBD): IBD is a chronic inflammatory disease of the gastrointestinal tract. It is divided into two types of intestinal diseases: ulcerative colitis (UC) and Crohn's disease (CD). The immune system attacks the lining of the intestines, causing symptoms of diarrhea, rectal bleeding, urgent bowel movements, abdominal pain, fever, and weight loss. In UC, inflammation leads to edema (swelling), ulcers, bleeding, and electrolyte imbalances. CD can affect any part of the GI tract causing inflammation.
- Multiple sclerosis (MS): MS is a chronic inflammatory autoimmune disease affecting the central nervous system (CNS). The immune system attacks nerve cells, causing symptoms that can include pain, muscle spasms, numbness, tingling, and burning sensation.
- Type 1 diabetes mellitus: Type 1 diabetes mellitus is a metabolic disorder characterized by increased blood sugar levels (hyperglycemia) due to insulin deficiency. It is characterized by the presence of polyuria (excessive urination), polydipsia (excessive thirst), weight loss, and weakness for a few days or weeks. Some patients may present with diabetic ketoacidosis. Microvascular complications include retinopathy (in eyes), nephropathy (in kidneys), and neuropathy (in nerves). Macrovascular complications include coronary artery, cerebrovascular, and peripheral vascular disease.
- Psoriasis: Psoriasis is an autoimmune disease affecting the skin. In psoriasis, immune system cells called T cells accumulate in the skin. The most common symptom of psoriasis is the formation of plaques which are dry, thick, and raised patches on the skin. These patches cause itching in the skin.
- Graves' disease: Hyperthyroidism (overactive thyroid) is the most commonly encountered symptom of Grave's disease. The immune system produces antibodies that stimulate the thyroid gland to release excessive thyroid hormone and decline in thyroid stimulating hormone levels in the blood leading to hyperthyroidism. The subsequent inflammation of the thyroid gland is responsible for its growth and bulging of the eyes, two typical symptoms of Graves' disease.
- Hashimoto's thyroiditis: Hypothyroidism (underactive thyroid) is the most commonly encountered symptom of Hashimoto's thyroiditis. In this disease autoantibodies produced by the immune system attack and slowly destroys the thyroid gland. As a result of this thyroid produces too little of the thyroid hormone leading to hypothyroidism. Symptoms include weight gain, cold sensitivity, fatigue, hair loss, constipation, depression, and dry skin.
- Myasthenia gravis: Myasthenia gravis is a disease characterized by muscle weakness. Symptoms of myasthenia gravis include weakness of muscles (eye muscles, neck muscles, throat muscles, and limb muscles) double vision, drooping eyelids, impaired speech, and problems in chewing, swallowing, and breathing.
- Scleroderma: Scleroderma is an autoimmune chronic connective disease characterized by the hardening of the skin. It is of two types: localized and systemic. Localized scleroderma affects the skin and the underlying structures only. Systemic scleroderma damage blood vessels and affects many internal organs, such as the heart, lungs, and kidneys. Inflammation occurs in this disease causing the body to make too much collagen, leading to visible hardening of the skin. There is damage to blood vessels and other internal organs, such as the heart, lungs, and kidneys.
- Sjogren’s syndrome: Sjögren's syndrome is a systemic autoimmune, rheumatic disease characterized by chronic dry eyes and dry mouth due to the damage of lachrymal and salivary glands. Other complications include other areas of dryness, internal organ involvement, neurological problems, and lymphomas.
Autoimmunity more common in women
Females are more prone to the development of autoimmune diseases; around three times more common in women than in men. The epidemiological statistics document that Sjogren's syndrome affects women in a 9:1 ratio; SLE affects women in a 7:1 ratio; rheumatoid arthritis affects women in a 3:1 ratio; and systemic sclerosis affects women in a 3:1 ratio.
Women undergo three main endocrinological transitions during their life: puberty, pregnancy, and menopause. These different phases display a significant effect on the innate and adaptive immune system due to interactions between the hormonal environment and pro-and anti-inflammatory cytokines.16 Many autoimmune disorders seem to affect women during pregnancy or during a great hormonal change.
Pregnancy challenge and hormonal changes in the onset of autoimmune diseases in women
Pregnancy results in various hormonal and bodily changes. Such changes elicit the development of autoimmune diseases. There are physiological changes such as increased basal metabolic rate, lipid levels, and weight gain that occur during pregnancy. Moreover, there are hormonal changes that occur during pregnancy leading to changes in the levels of hormones such as estriol, progesterone, and prolactin.
Hormonal changes also during the post-partum (after pregnancy) period lead to an increased incidence of certain autoimmune diseases, such as rheumatoid arthritis. Studies document an increased incidence ratio of 1: 7 for rheumatoid arthritis in the 24 months after delivery.