Familial Sarcoidosis

Generalized sarcoidosis is becoming recognized as a common disease, but its etiology remains unknown. For years, tuberculosis was considered the most likely underlying cause; however, as time has passed, it has become recognized as a probable complication rather than a cause.¹Specific agents such as helminths,²beryllium,³,⁴histoplasma,⁵,⁶cryptococci,⁷and foreign bodies⁸,⁹have been associated with isolated cases, but by no means can they account for the pathogenesis in the vast majority of involved patients. Recently, environmental influences have been considered as a potential etiologic factor. This idea evolved from the work by Michael et al.,¹⁰who, in 1950, reviewed 226 cases from military personnel, and discovered that most were born in rural areas of the southern section of the United States. In 1955, Gentry, Nitowsky and Michael¹¹published an extensive survey of 297 veterans showing that the birthplace and residence when inducted into the service correlated with an