Portal Hypertension Due to Schistosomiasis Mansoni' MARIO R. GARCIA-PALMIERI, M.D. and RAUL A. MARCIAL-ROJAS, M.D. San Juan, Puerto Rico THE predominant clinical features of a small percentage of patients suffering from schis- tosomiasis mansoni appear to be the result of obstructive vascular phenomena occurring in the liver or in the lungs [1-3]..