This article was last reviewed on
This article waslast modified on October 10, 2017.
What is Sarcoidosis?

Sarcoidosis is a condition in which inflammatory cells produce nodules called granulomas in multiple organs. Granulomas can develop anywhere in the body, but they commonly affect the lungs, skin, lymph nodes, and eyes. Granulomas change the structure of the tissues around them and, in sufficient numbers, can cause inflammation, damage, and symptoms related to that tissue.

The cause of sarcoidosis is not known. The condition is thought to be associated with both a genetic predisposition and the immune system's reaction to an environmental trigger, such as exposure to a virus, bacteria, allergen, or chemical. Anyone can develop sarcoidosis, but it most frequently occurs in adults of African or Northern European descent who are 20 to 40 years of age. African Americans are the most affected group in the U.S. The Foundation for Sarcoidosis Research states that nearly 2% of the African American population may be affected. Research also suggests a higher rate of disease for women.

Sarcoidosis varies in severity. A person may have the disease without knowing it since mild cases cause few, if any, symptoms and the symptoms may be nonspecific. It can present as an acute illness that resolves on its own within a few years (remission) and may or may not recur. Sarcoidosis can also be a chronic disease that continues over time. According to the National Heart Lung and Blood Institute, more than half of those affected will go into remission within 3 years of diagnosis, and two-thirds will be in remission within 10 years.

Most people with sarcoidosis will not experience long-term health effects, but about one-third will have some degree of organ damage. Sarcoidosis can cause blindness in rare cases and can sometimes be fatal, primarily in those with severe lung or heart involvement.

Accordion Title
About Sarcoidosis
  • Signs and Symptoms

    The severity of sarcoidosis and the symptoms a person experiences depend upon the tissues and organs affected. A person may have no symptoms or may have nonspecific findings such as:

    • Fever
    • Fatigue
    • Weight loss
    • Night sweats
    • Loss of appetite
    • Swollen lymph nodes
    • Joint pain

    Signs and symptoms associated with specific organs are listed below.

    Lungs
    The American Lung Association estimates that as many as 90% of those with sarcoidosis will have lung involvement. Lung tissues can stiffen and scar tissue may develop. Symptoms include:

    • Dry cough
    • Wheezing
    • Shortness of breath
    • Chest pain


    Skin
    Up to 25% of those with sarcoidosis have skin problems, including:

    • Sores on or near the cheeks, ears, nose, and eyelids
    • A raised, reddish, bumpy rash on the ankles or shins that may itch or be tender and warm
    • Discolored skin
    • Inflammation and nodules around scars


    Eyes

    • Blurred vision
    • Sensitivity to light
    • Eye pain and itching
    • Burning and redness
    • Tears
    • Inflammation


    Heart


    Brain and Nervous System

    • Headaches
    • Weakness
    • Seizures
    • Decreased coordination and tremors


    Muscle and Bone

    • Pain
    • Joint stiffness

    Sarcoidosis can also cause kidney and liver dysfunction, an enlarged liver or spleen, and swollen salivary glands. Granulomas produce activated vitamin D (1,25-dihydroxyvitamin D), which causes the intestines to absorb more calcium, leading to increased calcium in the blood and urine and the formation of kidney stones. In rare cases, it may cause kidney failure.

  • Tests

    The goals of testing are to diagnose sarcoidosis, evaluate its severity, and monitor its course over time. Testing is also used to distinguish sarcoidosis from conditions with similar symptoms and from conditions that are also associated with the development of granulomas, such as tuberculosis and some fungal infections.

    Laboratory Tests

    Tissue biopsy is the primary test used to confirm a diagnosis of sarcoidosis; characteristic changes in the structure of the tissue can be seen under the microscope. Other laboratory tests are not specific for sarcoidosis, but they are helpful in assessing disease activity, looking for damage to individual organs, and ruling out other diseases that may cause similar problems. Tests that may be useful include:


    Non-laboratory Tests

    • Chest X-ray - a common and useful test for detecting lung involvement; in people without symptoms, granulomas may first be discovered when they have an X-ray for another reason.
    • Lung function tests are performed to evaluate lung involvement and its severity. (For more on these, read Johns Hopkins Medicine Health Library: Pulmonary Function Tests.)
    • CT (computed tomography), MRI (magnetic resonance imaging), gallium scan, or other imaging scans are sometimes ordered to help diagnose and evaluate sarcoidosis. (Visit RadiologyInfo.org for additional details on these imaging tests.)
    • EKG (electrocardiogram) - sometimes ordered when heart involvement is suspected
  • Treatment

    There is no way to prevent or cure sarcoidosis, but in many cases it will resolve on its own over time. The goals of treatment are to relieve symptoms, decrease inflammation, and to minimize tissue and organ damage. People who have few or mild symptoms may not need treatment, but their condition should be monitored.

    Those with moderate to severe symptoms and those at risk for tissue or organ damage are usually treated with corticosteroids such as prednisone. These anti-inflammatory medications may be given orally, topically, or through an inhaler. Long-term use of corticosteroids can cause significant side-effects.

    Other medications may include:

    • Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen for pain and inflammation
    • Methotrexate and other drugs that suppress the immune system for lung, skin, or eye involvement
    • Hydroxychloroquine (an anti-malarial drug) may be useful for skin and nervous system involvement, especially in people who have increased calcium levels.


    Most people can be successfully treated, but they may need to take medications for an extended period of time. Rarely, a person may need an organ transplant if the lungs or liver have become severely damaged.

View Sources

NOTE: This article is based on research that utilizes the sources cited here as well as the collective experience of the Lab Tests Online Editorial Review Board. This article is periodically reviewed by the Editorial Board and may be updated as a result of the review. Any new sources cited will be added to the list and distinguished from the original sources used. To access online sources, copy and paste the URL into your browser.

Sources Used in Current Review

Cleveland Clinic. 2014. Diseases & Conditions: How Sarcoidosis is Diagnosed. Available online at https://my.clevelandclinic.org/health/diseases_conditions/hic_Overview_of_Sarcoidosis/hic_How_Sarcoidosis_is_Diagnosed. Accessed October 1, 2015.

Foundation for Sarcoidosis Research. 2014. What is Sarcoidosis? Available online at https://www.stopsarcoidosis.org/patient-resources/what-is-sarcoidosis/. Accessed October 2, 2015.

Mayo Clinic. 2013. Diseases and Conditions: Sarcoidosis. Available online at http://www.mayoclinic.org/diseases-conditions/sarcoidosis/basics/symptoms/con-20022569. Accessed October 1, 2015.

National Institute of Health. National Heart, Lung and Blood Institute. 2013. What is Sarcoidosis? Available online at http://www.nhlbi.nih.gov/health/health-topics/topics/sarc. Accessed October 1, 2015.

Sources Used in Previous Reviews

(2011 May 1). What Is Sarcoidosis? National Heart Lung and Blood Institute [On-line information]. Available online at http://www.nhlbi.nih.gov/health/health-topics/topics/sarc/. Accessed September 2011.

(© 2011). Sarcoidosis. American Lung Association [On-line information]. Available online at http://www.lungusa.org/lung-disease/sarcoidosis/. Accessed September 2011.

Mayo Clinic Staff (2010 July 15). Sarcoidosis. Mayo Clinic.com [On-line information]. Available online at http://www.mayoclinic.com/print/sarcoidosis/DS00251/DSECTION=all&METHOD=print. Accessed September 2011.

Dugdale, D. (Updated 2011 June 2). Sarcoidosis. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/000076.htm. Accessed September 2011.

Kamangar, N. and Shorr, A. (Updated 2011 July 29). Sarcoidosis. Medscape Reference [On-line information]. Available online at http://emedicine.medscape.com/article/301914-overview#showall. Accessed September 2011.

(Updated 2011 January). Sarcoidosis. American Academy of Family Physicians [On-line information]. Available online at http://familydoctor.org/online/famdocen/home/common/autoimmune/disorders/320.printerview.html. Accessed September 2011.

Grenache, D, and Roberts, W. (Updated 2010 October). Sarcoidosis. ARUP Consult [On-line information]. Available online at http://www.arupconsult.com/Topics/Sarcoidosis.html. Accessed September 2011.

(© 2010). Sarcoidosis Diagnosis. Foundation for Sarcoidosis Research [On-line information]. Available online at http://www.stopsarcoidosis.org/sarcoidosis/diagnosis.htm. Accessed September 2011.

Nikhar, N.K. and Mani, H. (2010 February 11). Sarcoidosis and Neuropathy. Medscape Reference [On-line information]. Available online at http://emedicine.medscape.com/article/1171907-overview. Accessed September 2011.

Newman, L. (Revised 2009 July). Sarcoidosis. Merck Manual for Healthcare Professionals [On-line information]. Available online at http://www.merckmanuals.com/professional/pulmonary_disorders/sarcoidosis/sarcoidosis.html. Accessed September 2011.

Cedars-Sinai. Sarcoidosis. Available online at http://www.cedars-sinai.edu/Patients/Health-Conditions/Sarcoidosis.aspx. Accessed January 2012.