Idiopathic Lymphocytic Pleuritis Responding to Corticosteroid Therapy

An 83-year-old man presented with chronic dyspnea, and chest X-ray showed bilateral pleural effusion. Right thoracentesis revealed lymphocyte-predominant exudate with no malignancy; bacterial and mycobacterial cultures were negative. Thoracoscopy via the right chest and a biopsy of the same site were performed; these showed lymphoplasmacytic infiltration and fibrosis, ruling out malignancy or tuberculosis. We decided to start corticosteroid therapy for the diagnosis of idiopathic lymphocytic pleuritis (ILP). The patient was discharged after clinical improvement, and steroids were tapered off. An early diagnosis by thoracoscopy and the exclusion of other diseases are important for initiating steroid therapy in patients with ILP.