++
A 42-year-old man presents with "multiple bumps" that had been growing on his scalp, the back of the neck, and on preexisting scars (Figure 184-1). These lesions started developing slowly over a period of 1 year. The differential diagnosis of these lesions included cutaneous sarcoidosis, acne keloidalis nuchae, and pseudofolliculitis barbae. A punch biopsy was performed and the diagnosis of sarcoidosis was made.
++
++
Sarcoidosis is a multisystem granulomatous disease most commonly involving the skin, lungs, lymph nodes, liver, and eyes. The condition more commonly affects patients of African descent compared to Caucasian patients. Diagnosing cutaneous sarcoidosis is critical, as 30% of these patients are later found to have systemic involvement. In addition, recent evidence has shown that approximately 25% of autopsies performed on patients with sarcoidosis revealed cardiac involvement.1 Nevertheless, the diverse presentations of cutaneous sarcoidosis in addition to variants of specific sarcoidosis syndromes can make for a diagnostic challenge.
++
Lupus pernio (cutaneous sarcoidosis).
Darier-Roussy disease (subcutaneous sarcoidosis).
Löfgren syndrome (erythema nodosum, hilar adenopathy, fever, arthritis).
++
Cutaneous manifestations occur in approximately 25% of systemic sarcoidosis patients.
In approximately one third of cases, cutaneous lesions are the first signs of systemic sarcoidosis.2
In the United States, the annual incidence is estimated at 35.5 per 100,000 persons of African descent and 10.9 per 100,000 Caucasians.3
The ratio of patients with only cutaneous sarcoidosis versus multisystem involvement is 1:3.
Specific cutaneous involvement is most common in older, female patients of African descent (Figures 184-2 and 184-3).
Common types of cutaneous lesions seen in sarcoidosis include erythema nodosum (EN); papular or plaque type, lupus pernio, cutaneous or subcutaneous nodules, and infiltrative scars.
EN occurs in 3% to 34% of patients with sarcoidosis and is the most common associated skin finding (see Chapter 186, Erythema Nodosum).
Sarcoidosis-related EN is more prevalent in Caucasians, especially Scandinavians. EN also has a predilection for Irish and Puerto Rican populations.
EN occurs between the second and fourth decades of life, more commonly in women.
Other nonspecific lesions of sarcoidosis reported include erythema multiforme, calcinosis cutis, prurigo, and lymphedema. Nail changes can include clubbing, onycholysis, subungual keratosis, and dystrophy, with or without underlying changes in the bone (cysts).
++++