[Spontaneous recovery from pancytopenia in a young female patient with paroxysmal nocturnal hemoglobinuria(PNH): changes in the GPI-anchor expression on peripheral blood cells].

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hemolytic disorder, caused by impaired cell surface expression of GPI-anchors in hematopoietic cells as a result of somatic mutation in the PIG-A gene, and often progresses into bone marrow aplasia. We experienced a girl diagnosed as having PNH with spontaneous recovery from pancytopenia, and analyzed the GPI-anchor expression on peripheral blood cells. Thrombocytopenia was first determined when she was 5-years old, and Ham and sugar water tests were negative at the age of 6 years. Subsequently, the pancytopenia slowly progressed, and the diagnosis of PNH was made at the age of 8 years based on the positive Ham test. Frame-shift of the PIG-A gene in exon 2 was confirmed in the peripheral granulocytes at the age of 11 years. Pancytopenia spontaneously subsided over two years after diagnosis, and an almost normal hematogram except for mild thrombocytopenia has been maintained for the subsequent 4 years. In periodical flow cytometric analysis of the CD55 expression on granulocytes and erythrocytes and the CD48 expression on lymphocytes, the population of the PNH clone was almost unchanged during the first two years of spontaneous recovery, but that of CD55-negative erythrocytes gradually decreased, suggesting that regression of PNH clone might be unnecessary in transient improvement of pancytopenia.

[Prevention of hepatic veno-occlusive disease by a combination of heparin and prostaglandin E1 in children undergoing hematopoietic stem cell transplantation].

The effect and safety of combination prophylaxis for hepatic veno-occlusive disease (VOD) following stem cell transplantation (SCT) was retrospectively evaluated in a total of 53 children who survived until day 30. Prophylaxis was started on the day before conditioning, and heparin (10 unit/kg/hr) alone was used in 6 patients, PGE1 (5 ng/kg/min) plus heparin plus PTX (200 mg/day) in 17 patients, lipo-PGE1 (0.5 ng/kg/min) plus heparin plus PTX in 7 patients, and lipo-PGE1 plus heparin in 23 patients. Diagnosis of VOD was made based on McDonald's criteria in 5 cases (9.4%), but not on Jones' criteria. No statistically significant difference was observed in the incidence of VOD among each prophylaxis group. The degree of VOD was mild in all of 5 cases, and all recovered with continuation of the prophylactic procedure. Each prophylactic procedure was performed without any significant adverse effect except for seizure induced by lipo-PGE1 in one patient with Lennox syndrome. Since both the incidence and fatality rate of VOD in children undergoing SCT are approximately 20% according to most of the previous reports, the present study suggests the effectiveness of combination prophylaxis.