What Is Sarcoidosis?
Sarcoidosis is a rare inflammatory disease in which clumps of inflammatory cells (called noncaseating granulomas) form in the body, most commonly in the lungs and lymph nodes in the chest cavity. It can also affect the heart, eyes, skin, and nervous system.
An acute, mild form of sarcoidosis is called Löfgren syndrome, which usually goes away within six months to two years after diagnosis.
What Are Symptoms of Sarcoidosis?
A small number of patients with sarcoidosis (about 5%) have no symptoms. When symptoms of sarcoidosis occur, they depend on the extent and severity of organ involvement, and may include:
- Shortness of breath on exertion
- Cough (and rarely, coughing up blood)
- Fever
- Loss of appetite
- Chest pain
- Swollen red or purple bumps, usually on the shins (erythema nodosum)
- Purple rash on the cheeks or nose
- Lupus pernio
- Eye inflammation (uveitis)
- Lesions on the eye
- Bone disorders
Uncommon/rare symptoms of sarcoidosis include:
- Skin lesions (maculopapular plaques)
- Heart failure from cardiomyopathy
- Heart arrhythmia, including heart block and sudden death
- Lymphocytic meningitis
- Cranial nerve palsies and hypothalamic/pituitary dysfunction
What Causes Sarcoidosis?
The cause of sarcoidosis is unknown. It is believed both genetic and environmental factors may play a role.
Risk factors for developing sarcoidosis include:
- Environment: Working in dusty or moldy environments
- Ethnicity: People of African and Scandinavian descent are at higher risk
- Gender: It is more common in women
- Age: Sarcoidosis more commonly develops in people between 20 to 40 years of age
How Is Sarcoidosis Diagnosed?
Sarcoidosis can be difficult to diagnose because the symptoms resemble many other conditions. If sarcoidosis is suspected, the following tests may be indicated:
- Breathing tests
- Pulmonary function tests
- Carbon monoxide diffusion capacity test
- Cardiopulmonary exercise testing
- CT scan of the chest
- Chest X-ray
- Gallium scans (less commonly used)
- Electrocardiogram (ECG or EKG) of the heart
- Lung tissue biopsy via bronchoscopy
- Blood tests to check for calcium, phosphate, and angiotensin-converting enzyme (ACE) levels
- Urine testing
- Eye exam
What Is the Treatment for Sarcoidosis?
Treatment for sarcoidosis depends on the severity of the disease and which organs are involved. Patients with mild symptoms may not require treatment.
Treatment may include:
- Nonsteroidal anti-inflammatory drugs (NSAIDs) for joint pain and rheumatologic symptoms
- Corticosteroids for lung inflammation
- Other non-steroid medications:
- Methotrexate (MTX)
- Chloroquine and hydroxychloroquine
- Cyclophosphamide
- Azathioprine
- Chlorambucil
- Cyclosporine
- Infliximab and thalidomide
For patients with advanced lung scarring (pulmonary fibrosis) from sarcoidosis, lung transplantation may be needed.
What Are Complications of Sarcoidosis?
Complications of sarcoidosis result from ongoing inflammation and may include:
- High levels of calcium in the blood (hypercalcemia) and high levels of calcium in urine (hypercalciuria)
- Suppressed parathyroid hormone (PTH)
- Low levels of vitamin D
- Eye problems
- Parasarcoidosis syndromes
- Fatigue
- Vitamin D dysregulation
- Skin lesions, usually on the legs (erythema nodosum)
- Nerve disorders or pain
- Depression
- Cognitive impairment
What Is the Staging for Sarcoidosis?
Sarcoidosis is staged as follows:
- Stage 0: Normal chest radiographic findings
- Stage I: Bilateral hilar lymphadenopathy
- Stage II: Bilateral hilar lymphadenopathy and infiltrates
- Stage III: Infiltrates alone
- Stage IV: Scarring (fibrosis)
What Is the Life Expectancy for Sarcoidosis?
There is no cure for sarcoidosis, and in many cases, no treatment is required and patients recover on their own. Most patients have a normal life expectancy.
About 1 to 8 percent of cases are fatal, and it depends on the severity and location of the disease. Signs of a poor prognosis include advanced scarring of the lungs (pulmonary fibrosis) and pulmonary hypertension. The majority (75%) of fatalities due to sarcoidosis are due to respiratory causes.