Sarcoidosis is an inflammatory condition that most commonly affects the lungs and lymph nodes, although it can affect other organs as well. It can sometimes be difficult to diagnose because there are a wide range of potential symptoms and, though certain individuals are known to have a relatively higher risk, the causes remain unknown.

Fortunately, many people with sarcoidosis experience no symptoms or only mild ones that don’t require treatment. And though the condition can become chronic, it’s not uncommon for it to go into remission after a few years, even without treatment. When that happens, it’s unlikely to cause future problems.  

Sarcoidosis affects women more frequently than men. It may strike anyone at any age, but people are most commonly diagnosed in their 20s, 30s, 40s or 50s. In nine out of 10 people with sarcoidosis, the condition affects the lungs. 

Some people experience permanent organ damage, while others eventually recover. A number of medications are available to treat sarcoidosis, including corticosteroids, which may help to manage or reverse symptoms.  

“It is important to know that sarcoidosis can be treated,” says Yale Medicine dermatologist William Damsky, MD, PhD. “At Yale, we have world-class sarcoidosis experts in many different medical specialties including pulmonology, cardiology, rheumatology, dermatology, ophthalmology, and others. At Yale, our specialists will always work together as a team to develop the best individualized treatment plan for each patient’s sarcoidosis.”

Sarcoidosis is a condition that causes inflammation within the lungs or other organs. Sometimes this leads to scarring. It may resolve on its own or become a chronic condition that requires ongoing treatment to protect various organs, including the lungs. 

In healthy people, the immune system fights off viruses, bacteria, and other unwanted invaders. In people with sarcoidosis, environmental triggers appear to prompt the immune system to become overactive in a setting where it’s not really necessary. 

This overactivation causes groups of immune cells to clump together within different organs, forming small lumps known as granulomas. These granuloma deposits may cause scarring within the organs over time. The condition may lead to a host of symptoms throughout the body, depending on the organ(s) affected.  

When sarcoidosis affects the lungs, a person may have a cough or difficulty breathing. It can also affect the heart, liver, spleen and other organs, as well as the skin.  

Sometimes, sarcoidosis is mild and doesn’t require treatment. When symptoms worsen, or when organ function is compromised, medication may help to improve the condition.

Doctors and researchers aren’t sure exactly what causes sarcoidosis. They believe that a person with a genetic predisposition for the condition may become affected after being exposed to certain chemicals or environmental triggers at work or at home. These include:

• Pesticide or insecticide
• Mold or mildew
• Metal dusts
• Combustible products 

When susceptible people are affected by triggers like these, their immune systems go into overdrive. This leads to inflammation in various sites around the body, such as the lungs or lymph nodes, and the formation of granulomas at those locations. The presence of granulomas may cause symptoms and organ damage that can lead to permanent scarring, though some people don’t experience any such changes.

Up to half of people with sarcoidosis don’t experience any symptoms and are diagnosed after getting an abnormal chest X-ray. Others may experience any among a wide range of symptoms, including:  

• Coughing or wheezing
• Shortness of breath or trouble breathing
• Chest pain
• Swollen lymph nodes
• A bumpy rash which may appear on the head and/or face, legs, or occasionally other areas
• Dizziness, lightheadedness, or fainting
• Palpitations or irregular heartbeat
• Fatigue
• Vision problems
• Inflammation of the sinuses and/or nose bleeds
• Joint pain, bone pain, or stiffness
• Feelings of discomfort
• Enlarged liver or spleen

Some people with sarcoidosis experience a combination of symptoms known as Löfgren syndrome. This includes a fever, enlarged lymph nodes, painful and swollen joints, eye pain with redness, and an inflammatory skin condition characterized by uncomfortable red lumps which appear beneath the skin. Löfgren syndrome often affects younger individuals and commonly goes away without treatment.

Sarcoidosis is more common in some population groups than others. It affects more women than men, for instance.  Risk is higher among those of Black American and/or Scandinavian descent, as well as in anyone with a family history of the condition. Sarcoidosis is sometimes also linked to taking certain medications, including monoclonal antibodies for other inflammatory conditions or specific cancer treatments. 

Exposure to certain chemicals or environmental triggers also may increase the risk of sarcoidosis. Careers that may increase a person’s risk include:  

• Agricultural employment
• Metal working
• Construction work and handling building supplies
• Workers in the automotive industry
• Firefighters

There is no single diagnostic test for sarcoidosis. When doctors suspect sarcoidosis, they ask about a family history of the condition or whether a patient works in an environment where they may be exposed to triggers. They’ll ask about medications, to see if anything on the list may be a risk factor. They will want to discuss a detailed history of symptoms.  

During a physical exam, doctors look for possible signs of sarcoidosis, including swollen lymph nodes, breathing difficulties (which they assess by listening to the lungs with a stethoscope), red bumps beneath the skin’s surface, other rashes or a swollen liver or spleen. They may also inquire about joint pain, eye, and sinus problems.  

Common tests a doctor may order to aid in diagnosis of sarcoidosis include:

• A chest X-ray or a CT scan, which may show abnormalities in the lungs, including inflammation (granulomas) or scar tissue
• A biopsy, which may confirm the presence of granulomas in the lungs, lymph nodes, or other organs including the skin
• Imaging tests, including MRI, ultrasound, or PET scan, which may be used to search for granulomas or inflammation in other parts of the body
• Blood tests, which may help to rule out other conditions
• Pulmonary function tests, which can see how well your lungs work
• Cardiac tests, such as electrocardiography or echocardiography, which can assess heart function

Not all people with sarcoidosis require treatment. For instance, doctors may choose to start with monitoring of the condition when people have mild symptoms or because certain treatments may cause unwanted side effects that outweigh their benefits.  

Doctors may recommend treatment when the lungs or heart are involved, when the condition causes neurological symptoms, or when symptoms become worse over time. 

Common treatments include:

• Corticosteroids, such as prednisone, which treat inflammation, help to reduce a variety of symptoms and improve function of the lungs and other affected organs
• Immunosuppressant medications, such as methotrexate (which may be given to a person who can’t tolerate corticosteroids or to try to reduce the dose of steroids) or the monoclonal antibody infliximab (e.g. a TNF-alpha inhibitor), which may help to improve lung and other symptoms
• Anti-malarial medications, such as hydroxychloroquine, which may help to improve skin conditions associated with sarcoidosis
• Other medications. Clinical trials at Yale are evaluating new treatments, including “JAK inhibitors.” 

During treatment, people will be monitored closely by their doctors. Individuals with sarcoidosis may be evaluated by multiple specialists to help follow the response to treatment in different organs, such as the lungs, eyes, and skin. The condition may recur or require ongoing treatment in some people.

More than half of people who have sarcoidosis recover within 2 to 5 years. For such patients, the condition goes into remission and they are unlikely to experience problems again.  

In other people, sarcoidosis becomes a chronic condition that may worsen over time. Remaining under the care of a physician may help to relieve symptoms.  

About 20% of people with sarcoidosis experience permanent lung damage. Roughly 5% of people with the condition die from respiratory failure caused by excessive scarring to lung tissue.

“Yale is a Foundation for Sarcoidosis Research [FSR]- and World Association of Sarcoidosis and Other Granulomatous disorders [WASOG]-designated Sarcoidosis Center of Excellence,” says Dr. Damsky. “Several sarcoidosis doctors and researchers at Yale are world experts and are working together to perform cutting-edge research in sarcoidosis. We are also evaluating new treatment approaches for sarcoidosis through clinical trials. At Yale, we are not only dedicated to improving the lives of the sarcoidosis patients we care for, but also to improving the lives of sarcoidosis patients around the world through research.”