Kinetic Studies of Lipid Exchanges in Red Cell Membranes in Hereditary High Red Cell Membrane Phosphatidylcholine Hemolytic Anemia : Reference to the Abnormal Accumulation of Phosphatidylcholine in These Membranes

The pathogenesis of the accumulation of phosphatidylcholine (PC) in red cell membranes of the patients with hereditary high red cell membrane phosphatidylcholine hemolytic anemia (HPCHA) was studied utilizing 14C-PC and 14C-lyso-PC. The uptake of 14C-PC was not significantly different in the red cell membranes with HPCHA from that in normal controls and obstructive jaundice in whom red cell membrane PC and free cholesterol (FC) were elevated to the same extent as that in HPCHA. The efflux of 14C-PC with HPCHA was slightly decreased, in comparison with that in the normal controls and obstructive jaundice. The most striking data were obtained in the uptake of 14C-lyso-PC by the red cells of the HPCHA patients, showing more than two fold increase when compared with that in the normal control. The conversion of 14C-lyso-PC to 14C-PC was increased in comparison with that in the normal controls and obstructive jaundice. In summary, the exact cause of the abnormal accumulation of PC through increased uptake of lyso-PC, followed by the increased conversion of lyso-PC to PC is unknown. In obstructive jaundice of an acquired origin, some compensatory mechanism may exist to prevent the further accumulation of lipids in the red cell membranes

Changes in Platelet Volume in Various Patients with Thrombocytopenia and Thrombocytosis as Observed by the Platelet Saponin Test

Platelet volume, the expansion ratio (ER) and the shrinkage ratio (SR) were measured by the platelet saponin test in various patients with thrombocytopenia and thrombocytosis. In patients with platelet counts of less than 10×10 4/μl the platelet volume increased to above the normal range (p<0.001, t-test) with reduction of the ER (p<0.001, t-test). The SR was heightened in thrombocytopenias due to diminished megakaryopoiesis resulting from enhanced platelet aggregation. On the other hand, in thrombocytopenias due to increased platelet destruction the SR level was normal notwithstanding and enlarged platelet volume presumably due to lowered platelet activity. In thrombocytosis with platelet count above 40×10 4/μl, both the platelet volume (p<0.05) and the ER (p<0.01, t-test) were smaller than in normal subjects. The numerical results obtained by the platelet saponin test reflect the qualitative platelet abnormalities in patients with thrombocytopenia and thrombocytosis

Paraproteinemia in a Patient with Acute Myelogenous Leukemia Derived from the Myelodysplastic Syndrome : A Case Report

Severe paraproteinemia was found in a 75-year-old female with acute myelogenous leukemia (AML) derived from refractory anemia with an excess of blasts, a type of the myelodysplastic syndrome (MDS). Immunoglobulin G-κ and G-λ paraproteins had increased in accordance with the proliferation of myeloblasts in her bone marrow. When the diagnosis of AML was made, a severe bleeding tendency and disturbance of consciousness due to the hyperviscosity syndrome were noted, although there was no significant increase in plasma cells in her bone marrow. An ultrasonogram disclosed multiple hyperechoic nodular lesions in the spleen. Cytoreductive therapy for AML was begun after plasma exchange, but she died of acute renal failure, subarachnoid hemorrhage, and the disseminated intravascular coagulation syndrome. Autopsy findings revealed clusters of plasma cells in the spleen and lymph nodes. The possibility that this coexistant paraproteinemia and AML were related to the evolution of a transformed clone in MDS is discussed