Refractory pleural effusion as a rare complication of pulmonary vascular stenosis induced by fibrosing mediastinitis: a case report and literature review

Fibrosing mediastinitis (FM) is a progressive, life-threatening disease characterized by extrinsic compression of mediastinal bronchovascular structures, and the clinical manifestations largely depend upon the affected structures. Pleural effusion is rarely reported in patients with FM. We herein describe a 70-year-old man who presented with recurrent breathlessness and refractory left pleural effusion. He was misdiagnosed with and treated for tuberculous pleurisy for several months. Thoracentesis revealed a transudative pleural effusion, and a contrast-enhanced computed tomography scan of the thorax showed an extensive mediastinal soft tissue mass consistent with FM. Pulmonary angiography demonstrated pulmonary artery stenosis on the right side and pulmonary vein stenosis mainly on the left side. After measurement of the pulmonary arterial pressure by right heart catheterization, the patient was diagnosed with pulmonary hypertension associated with FM. He underwent balloon angioplasty and stent implantation of the stenosed pulmonary vessels, which led to long-term improvement in his breathlessness and pleural effusion. Our systematic review of the literature highlights that pleural effusion can be an uncommon complication of FM and requires careful etiological differentiation.