Abstract
The sera from 112 cases clinically diagnosed as sarcoidosis were available for testing. Sera were derived from centers in 11 states in this country and from centers in Sweden, France and Scotland. Sera were diffused in agar using a plate modification of Crowle''s slide technique against mycobacterial antigens representating human strain of tuberculosis and Group I, II and III, Runyon strains. They were also tested against mycotic antigens which included those of blastomyces, histoplasma, coccidioides and cryptococcus. Eighty-eight of 112 sera contained precipitating antibodies against the Bunyon strains of unclassified mycobacteria. Of these 88 nine also possessed antibodies against human tuberculosis and 11 sera showed antibodies against one or more of the fungi. Sera from 4 individuals showed increase in extent of reaction as primary sarcoidosis improved. Reactions seemed to diminish in extent as sarcoidosis reached late inactive or progressive stages. Several explanations of these antibodies in the sera of sarcoidosis are discussed. The high rate of reaction may have diagnostic possibilities and tends to supports the opinion that sarcoidosis may be an entity.