Pulmonary capillary hemangiomatosis

Pulmonary capillary hemangiomatosis, abbreviated PCH, is a disease of the blood vessels of the lungs in which abnormal proliferation of capillaries and fibrous thickening of the inner lining of the veins produce a progressive rise in vascular resistance. It is a rare cause of pulmonary hypertension and occurs predominantly in young adults. Together with pulmonary veno-occlusive disease, PCH makes up the World Health Organization Group I prime category of causes of pulmonary hypertension. There is some evidence that PCH and pulmonary veno-occlusive disease may be different forms of a similar disease process.