SarcoidosisSarcoidosis is the growth of small collections of inflammatory cells (called granulomas) in different body parts, especially the lungs, lymph nodes, eyes, and skin. No one is certain what causes sarcoidosis, but experts believe it occurs when the body’s immune system reacts to an unknown substance that is likely inhaled. It may occur in people with a genetic predisposition and/or may be triggered by specific germs or chemicals.

Sarcoidosis symptoms mimic many other conditions. Fatigue, fever, weight loss, or swollen lymph nodes may occur. When sarcoidosis affects the lungs, it typically causes a dry, persistent cough, shortness of breath, wheezing, and chest pain. Symptoms may appear suddenly and then just as quickly disappear, or they may gradually develop. As granulomas grow, they can compromise the health of an organ, including the lungs.

A physical exam may be combined with x-rays, a CT scan, a PET or MRI study, blood tests, a biopsy using a bronchoscope, or lung function tests to diagnose sarcoidosis. Regular chest x-rays may monitor the condition over time. Corticosteroids, anti-rejection medications or TNF-alpha inhibitors may also be recommended to reduce inflammation if organ systems are threatened.

Sarcoidosis is most common in people ages 20 to 40 years. Women, African-Americans, and those with a family history of the disease appear to be more likely than other populations to develop the disease.

In the majority of otherwise healthy people, sarcoidosis may heal on its own, but left untreated, pulmonary sarcoidosis can cause permanent damage to lung tissue, causing pain or difficulty breathing.

Learn more about sarcoidosis from the National Heart, Lung, and Blood Institute .