A 48 y old woman with unremarkable medical history was admitted with bilateral pleural effusions; even though the fluid was drained, it re-accumulated and necessitated many repeated drainages in the following 2.5 y (56 hospitalisations). The patient underwent an extensive diagnostic work-up that disclosed elevated serum antinuclear antibodies, serum anti-dsDNA antibodies, pleural fluid anti-dsDNA and decreased pleural fluid C3 and C4. During that period she has been treated with a variety of immunomodulating agents, several pleural talcage and pleurectomy, without any apparent response. Thereafter, she received six courses of IVIg (2 g/kg body weight) in monthly intervals, followed by four months treatment with cyclosporin. This treatment resulted in gradual and eventually complete disappearance of the pleural effusion, and now after more than 2 y the patient is free of symptoms and receives no further medications.