Sarcoidosis is a condition in which groups of cells in your immune system form small, red, and swollen (inflamed) lumps. These lumps are called granulomas. They can form in any organ in the body. But they most commonly affect the lungs and lymph nodes in the chest. Over time, sarcoidosis can cause permanent scarring of organs.

Your immune system creates inflammation to help defend you against germs and sickness. But in sarcoidosis, inflammation goes off track. It causes the cells in your immune system to form granulomas. Studies suggest that this inflammation might be triggered by infections and certain substances in the environment such as insecticides and mold. And your genes may affect how your immune system reacts to a trigger.

Anyone can develop sarcoidosis, but you are more likely to have it if you:

• Are older, especially if you are over age 55
• Live or work near insecticides, mold, or other substances that may cause inflammation
• Have a close relative who has sarcoidosis
• Take certain medicines, such as some types of HIV medicines and monoclonal antibodies
• Are of African or Scandinavian descent
• Are female

Many people who have sarcoidosis have no symptoms, or they may feel unwell but without any obvious symptoms. If you have symptoms, you may have some general symptoms. And you may have other symptoms, which will depend upon which part of the body is affected.

The general symptoms can include:

• Fatigue
• Weight loss
• Swollen lymph nodes
• Depression
• Fever
• Night sweats (heavy sweating during sleep)

The symptoms of sarcoidosis in the lungs can include:

• Wheezing
• Cough
• Shortness of breath
• Chest pain

The symptoms of sarcoidosis in other parts of the body can include:

• Larger than normal liver or spleen
• Jaundice, which can make your eyes or skin yellow
• Nervous system problems, such as:
  • Headache
  • Dizziness
  • Vision problems
  • Seizures
  • Numbness or tingling
• Heart palpitations or an irregular heartbeat (arrhythmia)
• Pain and swelling in the joints
• Skin problems such as rashes and growths under the skin

There is also a set of symptoms that are called Lofgren's syndrome. Some people have Lofgren's syndrome when they first develop sarcoidosis. It usually goes away completely within 2 years. The symptoms of Lofgren's syndrome may include:

• Swollen lymph nodes in your chest, neck, chin, armpits, or groin.
• A rash of small, itchy, or painful bumps called erythema nodosum. The rash is most often on your head, neck, or legs.
• Blurred vision, eye pain or redness, light sensitivity, or watery eyes.
• Joint pain, stiffness, or swelling.
• Fever.

If untreated, or if the treatment does not work, sarcoidosis can cause serious health problems called complications. Possible complications include:

• Lung problems
• Heart problems
• Hormone problems
• Brain, nerve, or muscle problems
• Kidney problems
• Severe organ damage

There is no single test that can diagnose sarcoidosis, and its symptoms can be similar to the symptoms of many other conditions. That makes it hard to diagnose. To find out if you have sarcoidosis, your health care provider:

• Will ask about your medical history, including your symptoms, lifestyle, and any other health conditions you may have.
• Will do a physical exam, which may include:
  • Checking your temperature
  • Checking to see if your lymph nodes, spleen, or liver are swollen
  • Listening to your chest with a stethoscope as you breathe in and out
  • Looking for rashes or sores on your body, such as scalp and lower legs
• Will likely order various tests, such as:
  • Chest x-rays
  • A biopsy of the skin, lymph nodes, lungs, or other affected organs
  • Blood tests to check your blood counts, hormone levels, and how well your kidneys are working
  • Other imaging tests

If you are diagnosed with sarcoidosis, your provider may order other tests to look at how sarcoidosis is affecting the body.

There is no cure for sarcoidosis. The goal of treatment for sarcoidosis is remission, which means you still have the condition, but it does not cause you problems.

You may not need treatment, and sometimes the condition goes away on its own. If you do need treatment, which treatment(s) you get will depend on your symptoms, which organs are affected, and whether those organs are working well. You may be given medicines to:

• Lower inflammation
• Treat an overactive immune response
• Treat joint pain
• Treat skin problems

If you have complications from sarcoidosis, you may need other treatments, such as other medicines, surgery, oxygen therapy, pulmonary rehabilitation, or an implanted cardiac pacemaker or defibrillator.

Whether or not you have symptoms from sarcoidosis, it's important to get regular follow-up care from your provider, make healthy lifestyle changes, and contact your provider if you have any new symptoms.

NIH: National Heart, Lung, and Blood Institute