What is sarcoidosis? It’s an inflammatory disease that most often affects your lungs and lymph nodes but can impact any organ in your body, including your eyes, skin and heart. Sarcoidosis is characterized by small clusters of inflamed cells, called granulomas, that form in the affected organ. Granulomas can alter the normal structure of the organ and interfere with its function.

Sarcoidosis affects between 150,000 and 200,000 people in the US and an estimated 1.2 million worldwide. Some people with sarcoidosis experience no signs and symptoms. When symptoms do appear – usually in people between the ages of 20 and 40 – they vary depending on the organ involved.

In many cases, people with sarcoidosis initially present with a classic set of signs and symptoms collectively referred to as Lofgren’s syndrome. Signs and symptoms associated with this syndrome include: fever, enlarged lymph nodes, swollen and painful joints, and a rash – typically found on the shins and ankles – that consists of raised red and tender bumps. This rash is called erythema nodosum.

Other common signs and symptoms of sarcoidosis include but are not limited to: fatigue; weight loss; irregular heartbeat; discoloration of the nose, cheeks, lips and ears; blurry vision; sensitivity to light, headaches; swollen legs; arm, leg or facial weakness; hoarse voice; enlarged liver or spleen; pain in your hands or feet; and a general feeling of ill health.

If your lungs are affected by sarcoidosis, you may experience shortness of breath, dry cough, chest pain or wheezing.

The exact cause of sarcoidosis is unknown. Some experts believe it results from an overreaction by your immune system to a foreign substance. These substances may include infectious agents, chemicals, dust and possibly your body’s own proteins. An immune system reaction causes inflammation. With sarcoidosis, inflamed cells collect and form granulomas.

Certain factors put you at a greater risk for developing sarcoidosis. These risk factors include: age; living or working near insecticides, mold or other substances that cause inflammation; family history of sarcoidosis; race or ethnicity – the condition is more common in people of African and Scandinavian descent; and gender – women are affected more often than men.

Diagnosing sarcoidosis can be challenging because its signs and symptoms are similar to those of other diseases. To make a diagnosis, your doctor will first review your medical history and perform a thorough physical exam. Tests your doctor may use to diagnosis sarcoidosis include: chest x-ray, high resolution CT scan, pulmonary function tests, bronchoscopy with biopsy, PET scan, gallium scan, blood tests, electrocardiogram and slit lamp test to examine your eyes.

In some people, particularly those who experience mild symptoms, sarcoidosis will resolve on its own without treatment. The goal of treatment, when it’s needed, is to reduce symptoms and maintain function of the affected organ.

Treatment of sarcoidosis begins with good health practices. You are encouraged to see your doctor routinely for check-ups, eat a balanced diet that includes plenty of fruits and vegetables, drink eight to 10 8-oz glasses of water daily, exercise regularly and manage your weight, get six to eight hours of sleep per night and quit smoking.

Medication treatment it typically reserved for people experiencing moderate to severe sarcoidosis symptoms. The oral corticosteroid prednisone, which reduces inflammation, is the most commonly used medication. Initially, a relatively high dose of corticosteroids is prescribed. This is followed by a slow tapering of the medication until the lowest effective dose is reached.

Unfortunately, corticosteroids, including prednisone, have side effects such as excessive weight gain, insomnia, acne and depression. Some people taking corticosteroids develop high blood pressure, cataracts, glaucoma, osteoporosis or diabetes. These medications also increase your risk for infection.

Other treatment options may be tried if you can’t take corticosteroids or find their side effects intolerable. For example, medications commonly used to treat arthritis, such as methotrexate and azathioprine, can suppress the inflammatory response of your immune system. These medications may be used in place of or together with corticosteroids. But they can be toxic to your liver, so regular blood tests to check liver function are necessary.

If the granulomas affect the function of an organ, you may develop complications, including permanent damage to your heart or lungs due to scarring of the tissue. So it’s important to visit your doctor as soon as you notice the signs and symptoms of sarcoidosis.