Definition and causes
Some diseases affect the body's connective tissues. The symptoms from these diseases are caused by the immune system mistakenly attacking the body's own tissues, causing an inflammatory reaction (inflammation).
The function of connective tissue is to support other tissues. It consists of a complex composition of various proteins, sugars, water, ions, salts and cells. Connective tissue is found in all organs, and the composition of the connective tissue is vital to the specific part of the body's mechanical properties. The vast majority of connective tissue consists of collagen and elastin, and their characteristics is to respectively strengthen the tissue and increase the elasticity of the tissue.
More than half of the body's proteins are made up of collagen, and diseases affecting the connective tissues are thus widespread throughout the body. Not all connective tissue diseases are however targeting collagen but can be aimed against many other components of the connective tissue.
The fundamental nature of the connective tissue diseases are that the immune system is directed against the body's own tissues. Normally the immune system fights harmful external organisms, such as bacteria and viruses, but connective tissue diseases give rise to the formation of antibodies, which can sit on the body's own tissue, which in turn are attacked by the immune defense cells. This leads to prolonged inflammation and subsequent tissue death. The reason for the formation of antibodies, is unknown but is believed to be caused by:
Connective tissue diseases typically affects: joints, muscles, tendons, skin, blood vessels, heart, lungs, kidneys and eyes. Look under the specific diseases for symptoms.
The various connective tissue diseases
Sjögrens syndrome is the most common. About 5,000 inhabitants in every million have the disease.
SLE (Lupus) is the second most common with about 300 per million inhabitants affected.
Arteritis temporalis, approximately 200 per million inhabitants are affected.
Dermato-polymyosistis, which is rare.
Scleroderma, which is rare.
Mixed connective tissue disease (MCTD), which is also rare.
Common features of connective tissue disease
The involvement of multiple organ systems. Joint symptoms are frequent, but less pronounced than in rheumatoid arthritis (RA).
Inflammatory reaction in blood vessels.
Treatment of connective tissue disease
Generally connective tissue disease is treated with anti-inflammatory and immuno suppressive drugs. The intensity of the treatment depends on the severity of the disease.
Prognosis and complications
The vast majority of diseases are chronic but have a varying course. The prognosis depends on the particular disease, but in some cases, early diagnosis and treatment (eg. Arteritis Temporalis) is very important for the prognosis.