SARCOIDOSIS - A multisystem disease process whose pathogenesis involves the formation of an inflammatory lesion known as a granuloma. Most patients with sarcoidosis are without symptoms. The disease is often detected on routine chest x-ray. When symptoms are present they include cough, shortness of breath, and arthritis. The lungs are the most frequently affected, but the eyes, nervous system, heart, kidneys, bones, and joints may also be affected.