Pulmonary veno-occlusive disease. A report of four cases.

Four cases of pulmonary veno-occlusive disease are described. Two patients, who were brothers, had respiratory tract infections. The third patient had chronic active hepatitis and coeliac disease suggesting an abnormality of the immune system; the fourth patient had no obvious cause but presented initially with systemic hypertension. Three of the cases had been diagnosed initially as primary pulmonary hypertension either on open lung biopsy or clinically. In all cases the pulmonary arteries were abnormal with medial hypertrophy, intimal fibrosis and, in some cases, thrombosis in elastic pulmonary arteries. These findings suggest that pulmonary veno-occlusive disease is not confined to veins and should be considered as a widespread pulmonary vascular disease. The range of aetiological factors indicate that it should not be considered as a single disease entity.