What is sarcoidosis?
Anthony L. Komaroff, MD
Internal Medicine
Sarcoidosis (pronounced sar-coy-DOE-sis) can be a terrible disease, but the severity can range greatly from one person to the next. I have some patients who have lived with it for many decades without it getting any worse and with little effect on their lives.

In sarcoidosis, the immune system attacks tissues and leaves little scars called granulomas. Granulomas can affect nearly every organ in the body, but often they're confined to just the lungs. Sarcoidosis is rare. Only about one or two people out of 10,000 have it in the United States. It tends to start before age 40, so if you are older than 40, the small chance that you will get sarcoidosis gets even smaller.

Despite more than 50 years of research, the cause is still a mystery. Many experts believe that there are multiple causes, which all contribute to triggering the damaging immune system response that leads to the granulomas. Infectious agents—bacteria or viruses of some kind—are among the suspects, but so far none has been identified as a cause.

Sarcoidosis can't be cured. Treatment is usually reserved for people experiencing symptoms, and drugs like prednisone and methotrexate that dampen the immune response are often quite effective. That's the good news, but the better news is that sarcoidosis is one of the many diseases that you will probably never get.
Harvard Medical School The Truth About Your Immune System

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Harvard Medical School The Truth About Your Immune System

Can you boost immunity? Will vitamins, herbs, or probiotics help your immune system fight off disease? What about diet and exercise? Your immune system is your most powerful protector but don't fall...

Sarcoidosis is an inflammatory condition in which clusters of irregular cells, known as granulomas, develop on one or more organs of the body. Sarcoidosis is thought to be caused by a disorder of the immune system, and can affect people of every age, sex and ethnicity. Symptoms of sarcoidosis can range from mild to severe, with potentially long-term complications.

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Immune & Lymphatic System Disorders

The lymphatic system is a key part of the immune system, draining excess fluid from bodily tissues and organs and disseminating white blood cells to fight infection. The white blood cells fight infection in the spleen and special ...

vessels throughout the body called lymph nodes. If your immune system becomes compromised, the lymphatic system wont be able to work properly, causing swelling from a buildup of fluid in parts of the body. Disorders of the lymphatic system include elephantiasis, a swelling of body parts caused by a filarial worm infestation, and lymphedema, a swelling in the arms or legs caused by lymph nodes or lymph vessels disturbed by surgery for breast or prostate cancer. Medication, massage therapy and compression garments can help.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.