Sarcoidosis is an autoimmune condition which results in the development of tiny collections of inflammatory cells in different parts of the body. These cells are called granulomas and they most commonly accumulate in the lungs, lymph nodes, eyes and skin.
Sarcoidosis results from the body’s immune system responding to an unknown substance, most likely something inhaled from the air. There is no cure for sarcoidosis, but most people do very well with minimal treatment and it often goes away on its own. But in some people it can persist for years and on occasion lead to organ damage.
Sarcoidosis is more common in people of African descent.
The exact cause of sarcoidosis is still unknown. Some people seem to have a genetic tendency to develop autoimmune diseases, which may be activated by exposure to certain bacteria, viruses, dust or chemicals. Researchers are still trying to identify the genes and exact processes connected with sarcoidosis.
Usually, your immune system helps protect your body from foreign substances and invading microorganisms, such as bacteria and viruses. But in sarcoidosis, some immune cells accumulate in a pattern of inflammation called granulomas. As granulomas build up in an organ, the function of that organ can be affected.
Many people with sarcoidosis have no symptoms, so the disease may be discovered only when a chest X-ray is done for another reason.
Swollen lymph glands
Persistent dry cough
Shortness of breath
Skin symptoms occur in about 25 % of people and include:
Rash consisting of red or reddish-purple bumps, typically found on the shins or ankles, which may be warm and tender to the touch.
Sores. Scarring skin eruptions may occur on the nose, cheeks and ears.
Colour change. Areas of skin may get darker or lighter in colour.
Nodules. Growths just under the skin may develop, particularly around scars or tattoos.
Eye symptoms include:
Sensitivity to light
Swelling or protrusion of the eye.
Sarcoidosis can however affect the eyes without causing any symptoms, so it’s important to have your eyes checked if you have been diagnosed with it.
For most people with sarcoidosis, the illness goes away on its own with no lasting problems. But sarcoidosis can be long-lasting (chronic) in some people and lead to problems that may upset different parts of your body:
Lungs: Untreated pulmonary sarcoidosis can lead to irreversible damage to the tissue between the air sacs in your lungs, making it difficult to breathe.
Eyes: Inflammation can affect almost any part of your eye and can result in blindness. Infrequently, sarcoidosis also can cause cataracts and glaucoma.
Kidneys: Sarcoidosis can affect how your body handles calcium, which can lead to kidney failure.
Heart: Granulomas can deposit in the heart and interfere with the electrical signals that drive the heartbeat, causing abnormal heart rhythms and, in rare cases, death.
Nervous system: In some people sarcoidosis causes problems related to the central nervous system when granulomas form in the brain and spinal cord.
Sarcoidosis can be difficult to diagnose because the disease produces few signs and symptoms in its early stages and like other autoimmune diseases manifestations can mimic those of other disorders.
Diagnostic tests can help exclude other disorders and determine what body systems may be affected by sarcoidosis. Your doctor may request:
X-ray: to check for evidence of lung damage or enlarged lymph nodes in your chest. Some people are diagnosed with the condition after chest X-rays taken for other reasons.
CT scan of the chest: if lung complications are suspected.
Blood tests: to assess your overall health and assess whether organs like your kidneys and liver are involved.
Lung function tests: to measure lung volume and how much oxygen your lungs deliver to your blood.
Eye exam: to check for vision problems that may be caused by sarcoidosis.
Biopsies: a small sample of tissue (biopsy) can be taken from a part of your body believed to be affected by sarcoidosis usually the skin, lymph nodes, or lungs to look for the granulomas commonly seen in the condition. The tissue is sent to a laboratory for analysis. Lung biopsies or lymph node biopsies can be obtained through a procedure (called bronchoscopy) in which a thin, flexible tube containing a camera is inserted down your throat.
There’s no cure for sarcoidosis. You may not need treatment if you don’t have significant signs and symptoms of the condition. Sarcoidosis often goes away on its own. But you should be monitored closely with regular chest X-rays and exams of the eyes, skin and any other organ involved.
If organ function is threatened, you will likely be treated with a medication.
Corticosteroids: These potent anti-inflammatory drugs are typically the standard treatment for sarcoidosis. In some cases, corticosteroids can be smeared directly on the affected area e.g. a cream to a skin lesion or with an inhaler to the lungs.
Immune-modulatory medications: These medications reduce inflammation by suppressing your immune system.
Anti-malarial medications: These medications e.g. hydroxychloroquine may be useful for skin disease, nervous system involvement and raised blood-calcium levels.
Tumor necrosis factor-alpha (TNF-alpha) inhibitors: These treatments are most frequently used to treat the inflammatory conditions and can also be helpful in treating sarcoidosis that doesn’t respond to other treatments.
Surgery: Organ transplant may be considered if sarcoidosis has severely damaged your lungs or liver.
Although sarcoidosis is not always serious, it can cause long-term damage to your organs. See your doctor if you experience signs and symptoms suggestive of sarcoidosis.
The writer is a Physician specialist/Rheumatologist