Vascular problems in paroxysmal nocturnal haemoglobinuria. A report of two cases.

Two patients with paroxysmal nocturnal haemoglobinuria (PNH) are described who had severe vascular complications. The first patient developed extensive thrombosis of the abdominal veins leading to intractable ascites symptomatically treated with a peritoneo-venous shunt. The second patient had aneurysm of the abdominal aorta treated with a prosthetic graft. Although in both patients prosthetic grafts were implanted no signs of an increased activation of the P.N.H. cells were found and no thrombosis or severe haemolytic anaemia occurred. It is suggested that surgical intervention for vascular complications in PNH should not be delayed because of fear of activating the PNH.