Sarcoidosis is a multisystem disorder characterized by noncaseating granulomatous inflammation at sites of disease.1 Although any organ can be involved, the disease most commonly affects the lungs and intrathoracic lymph nodes. A diagnosis of sarcoidosis is most securely established from compatible clinical and radiologic findings, confirmed by a biopsy showing noncaseating epithelioid granulomas in more than one organ and the exclusion of granulomatous disorders of known cause. Clinical, epidemiologic, and family studies support the hypothesis that sarcoidosis is triggered by exposure to microbial agents in individuals with a genetic susceptibility to the disease. The clinical course is highly variable, with a mortality rate of <1% to 5%. Corticosteroids remain the mainstay of treatment for patients with threatened organ failure or progressive disease.
Jonathan Hutchinson was the first to describe a case of sarcoidosis in 1887; he called it Mortimer’s malady, after one of his patients who presented with face and limb skin lesions. In 1889, Besnier of Paris described a 34-year-old man with violaceous skin lesions of the nose, ear lobules, and central face; he proposed that the lesions were a variant of lupus erythematosus leading to its designation as “lupus pernio.” In 1899, Caesar Boeck first described the characteristic noncaseating granulomas in a patient with peripheral lymphadenopathy and skin nodules. He proposed the term multiple benign sarcoids of the skin because he thought the granulomatous changes resembled sarcomatous tissue. Subsequently, descriptions of sarcoid-type lesions in the eyes, bones, lungs, and salivary glands were made, but the systemic and unifying nature of sarcoidosis was not recognized for almost 20 years.
The view that sarcoidosis is a systemic disorder is largely based on the work of Jorgen Schaumann, a Swedish dermatologist, who in 1914 presented the view that Besnier lupus pernio and Boeck’s multiple sarcoids were manifestations of the same disease termed “lymphogranulomatose benigne,” thought to represent a variant of tuberculosis. In 1935, Williams and Nickerson reported that intradermal inoculation of a suspension of sarcoidosis tissue resulted in firm papules in patients with suspected sarcoidosis. Ansgar Kveim demonstrated that these papules contained sarcoidosis-like granulomas on biopsy. Louis Siltzbach and others would demonstrate in worldwide studies that this “Kveim” reaction was positive (showed granulomas) in up to 80% of sarcoidosis and was highly specific for the disease. Sven Löfgren of Sweden in the 1940s noted that sarcoidosis frequently begins with asymptomatic bilateral hilar adenopathy or with acute erythema nodosum. In the 1950s, corticosteroids were reported to be successful in treating sarcoidosis. More recently, the tools of cell and molecular biology have advanced our understanding of the immunologic, genetic, and etiologic basis of sarcoidosis, but have not yet led to breakthroughs in the development of safe, effective therapies or cure.
Sarcoidosis is found worldwide, although the frequency of the disease varies among different geographic regions. Accurate measurements of disease prevalence are ...