Sarcoidosis is a disease which can affect any organ of the body, although it most commonly affects the lungs, eyes, lymph nodes and skin.
The body’s immune system generally protects against foreign and harmful substances, for example viruses, bacteria and chemicals. The body ordinarily responds by releasing white blood cells to the affected organ. These cells produce chemicals that cause inflammation to break up and destroy the foreign particles.
Sarcoidosis is thought to occur as a result of an abnormal immune response where the body believes itself to be under attack and triggers an immune reaction. An excess build up of white blood cells leads to the formation of granulomas on the affected organ. Granulomas are clusters of these defensive cells that grow together to form lumps. They can impair the function of the organ thus causing the symptoms of sarcoidosis. These granulomas usually resolve on their own or following medication, however in a small number of cases permanent scarring (fibrosis) can occur which is why early detection and treatment of sarcoidosis is important.
Sarcoidosis is not a cancerous or contagious disease.