Idiopathic pulmonary hilar fibrosis: an unusual cause of pulmonary hypertension.

A 37-year-old man with progressive exertional dyspnea had pulmonary hypertension associated with pulmonary arterial and venous obstruction. An autopsy revealed that the cause of death was idiopathic pulmonary hilar fibrosis, a variant of mediastinal fibrosis. Pulmonary hilar fibrosis can mimic thromboembolic pulmonary hypertension, pulmonary veno-occlusive disease, and pulmonary venous hypertension.