Case Report Acta Haematol 2003;110:193–196 DOI: 10.1159/000074224 Splenectomy for Massive Splenic Infarction Unmasks Paroxysmal Nocturnal Hemoglobinuria Costas Tsatalas a Dimitris Margaritis a Despina Pantelidou a Ioannis Kotsianidis a Anastasios J. Karayiannakis b Emanuel Spanoudakis a Zafiris Kartasis a Vasiliki Kaloutsi d Alexandros Polychronidis b Ioannis Manavis c George Bourikas a a Department of Hematology, b Second Surgical Department and c Department of Radiology, School of Medicine, Democritus University of Thrace, Alexandroupolis, and d Department of Pathology, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece Received: March 25, 2003 Accepted after revision: July 14, 2003 C. Tsatalas, MD Department of Hematology, School of Medicine Democritus University of Thrace, Ioakim Kaviri 6 GR–68100 Alexandroupolis (Greece) Tel. +32 5510 76152, Fax +32 5510 76154, E-Mail ktsatala@med.duth.gr ABC Fax + 41 61 306 12 34 E-Mail karger@karger.ch www.karger.com © 2003 S. Karger AG, Basel 0001–5792/03/1104–0193$19.50/0 Accessible online at: www.karger.com/aha Key Words Paroxysmal nocturnal hemoglobinuria W Splenic infarction W Splenic vein thrombosis W Splenectomy Abstract Paroxysmal nocturnal hemoglobinuria (PNH) is a rare disorder characterized by pancytopenia, hemolysis, and thrombosis. Abdominal vein thrombosis is a life-threat- ening manifestation of this disease. We present a patient with complete spleen necrosis due to thrombosis of the splenic vessels. After splenectomy, other causes of thrombophilia were excluded and the diagnosis of PNH was established. The patient was put on anticoagulation but despite the prophylactic international normalized ratio maintained over the last 18 months of follow-up, he had another episode of intrahepatic thrombosis which was treated with tissue plasminogen activator thrombo- lysis. Copyright © 2003 S. Karger AG, Basel Introduction Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal disorder of the hematopoietic stem cell that results in the production of abnormal blood cells. These cells are deficient in all surface proteins which are normally attached to the cell membrane by a glycosyl- phosphatidylinositol (GPI) anchor. The abnormal GPI molecules in PNH are the result of a somatic mutation of the PIG-A gene which encodes a protein necessary for their biosynthesis. The disease presents with various clini- cal manifestations depending on the size of the abnormal clone and the most affected blood cells. PNH is mainly characterized by intravascular hemolysis with hemoglo- binuria and life-threatening thrombosis [1]. Although ve- nous thrombosis is a frequent complication in PNH patients, arterial thrombosis is rare and only a few cases have been reported [2, 3]. Here, we report a patient in whom the diagnosis of PNH was made after total splenic parenchymal necrosis due to thrombosis of the splenic vessels.