Spectrum of pleural involvement in sarcoidosis.

Pleural involvement has generally been considered an unusual aspect of sarcoidosis. In this paper, five previously unreported cases of sarcoidosis involving the pleura were discussed. Pleural sarcoidosis may be manifested by the presence of a pleural effusion, and the diagnosis is based on the exclusion of all other possible causes and the demonstration of noncaseating granulomas in the pleura. When the pleura is involved without effusion, it may only be recognized if noncaseating granulomas involving the pleura are looked for specifically. Including the five cases form this study, there have been 73 cases of pleural sarcoidosis reported, but only 37 have been verified by histologic evidence. When strict diagnostic criteria are used, clinical involvement of the pleura in sarsoidosis remains an unusual entity, but it may be that histologic involvement of the pleura is more common than generally appreciated.