Bloody pleural effusion--a rare manifestation of sarcoidosis.

Sarcoidosis is a multisystemic granulomatous disease of unknown etiology. Pleural effusion is rare in patients with sarcoidosis, occurring in 0.7% to 20% of cumulative series. Bloody pleural effusion is even more rare. We herein report two cases of sarcoidosis with bloody pleural effusion and discuss the clinical manifestations, diagnostic procedures and treatment of these cases. Sarcoidosis should be included in the differential diagnosis when bloody pleural effusions are detected. An increased level of lymphocytes and an increased ratio of CD4+/CD8+ lymphocytes in bronchoalveolar lavage fluid (BALF) are helpful for making a diagnosis of sarcoidosis. Medical thoracoscopy is helpful for determining the definitive diagnosis. Corticosteroids are an effective treatment; however, the dose should be individualized according to the treatment response.