Sarcoidosis

Key Points
Granulomatous condition which develops in the lungs, but may affect various organs including the skin
Exact cause is unknown, but is thought to be an immune disorder
Cutaneous symptoms consist of lesions of varying type, which may be accompanied by itching and thickening of skin

Sarcoidosis is a granulomatous condition which initially develops in the lungs and may involve various other organs, including the skin. The condition initially consists of various respiratory symptoms, such as coughing, shortness of breath, painful breathing, tightness in the chest, and may be accompanied by sinus congestion. Additional symptoms may include weight loss, loss of appetite, fatigue, fever, and chills or night sweats. Presentation of cutaneous symptoms varies widely, and may include specific or non-specific lesions. Non-specific lesions appear similar to other skin conditions, such as erythema nodosum or multiforme, nummular eczema, calcinosis cutis, and severe itching. Specific lesions may consist of large, thickened nodules which are bluish-red to purple in color (forming on the face, ears, and digits), circular plaques which are reddish purple to brown in color, maculopapular eruptions, nodules which form in the deeper layers of the skin, and thickening of scar tissue in the affected area. Additionally, the condition may involve other organs, such as the eyes, liver, heart, nervous system, muscular and skeletal systems. The condition may also affect calcium metabolism.

The exact cause of Sarcoidosis is unknown, though it is thought that it may be a disorder of the immune system. Though the condition may affect anyone regardless of ethnic, gender or age group, it typically develops from 20 to 40 years of age. Persons of African American (especially women), Scandanavian, German, Irish or Puerto Rican descent are at increased risk of developing the condition.

Differential Diagnosis (Other conditions with similar appearance)
Acute Retinal Necrosis
Leiomyoma, Iris
Amblyopia
Lyme disease

Diagnosis
Key Points
Diagnosis based on the characteristic appearance of the affected area in conjunction with clinical symptoms
Various imaging, laboratory and organ function testing may be performed to confirm diagnosis and rule out other conditions

Sarcoidosis is typically diagnosed based on the characteristic appearance of the affected area in conjunction with the clinical presentation of symptoms. Various imaging, laboratory and organ function testing may be performed to confirm the diagnosis and to rule out similar appearing conditions.

Treatment
Treatment is not typically required, as most cases are self-resolving and non-disabling
The primary goal of treatment is symptom management and maintaining function of affected organs
In a small number of cases, the condition may be fatal

Sarcoidosis does not typically require treatment, as most cases are self-resolving and non-disabling. The primary goal of treatment is to manage symptoms and maintain function of any affected organs. Treatment typically consists of the administration of systemic or topical corticosteroids, and treatment courses may persist for several years, as cutaneous symptoms tend to be more persistent. In the case of lesions which are disfiguring, laser therapies have been used with success. In a small percentage of cases, typically involving internal organs, the condition may be fatal.