The OnControl bone marrow biopsy technique is superior to the standard manual technique for hematologists-in-training: a prospective, randomized comparison

The purpose of this study was to compare a novel bone marrow device with the standard marrow needle in a prospective, randomized study in a teaching hospital employing hematologists-in-training. The new device, the OnControl Bone Marrow (OBM) Biopsy System, utilizes a battery-powered drill to insert the needle. Fifty-four bone marrows (27 standard and 27 OBM) were performed by 11 fellows under the observation and supervision of 3 attending hematologists and 1 research technologist. The primary endpoint of the study, the mean length of the marrow biopsy specimens, a surrogate for marrow quality, was determined by a pathologist in a blinded manner. The mean length of the marrow biopsy specimens was significantly longer (56%) for the OBM group (15.3 mm) than for the standard bone marrow (SBM) group (9.8 mm), P<0.003. An objectively determined secondary endpoint; mean procedure time, skin-to-skin; also favored the OBM group (175 s) versus the SBM group (292 s), P<0.007. Several subjective secondary endpoints also favored the OBM group. Only minor adverse events were encountered in the OBM and SBM study groups. It was concluded that bone marrow procedures (BMPs) performed by hematologists-in-training were significantly faster and superior in quality when performed with the OBM compared to the SBM. These data suggest that the OBM may be considered a new standard of care for adult hematology patients. OBM also appears to be a superior method for training hematology fellows

Response of Paroxysmal Nocturnal Hemoglobinuria Clone with Aplastic Anemia to Rituximab

Paroxysmal nocturnal hemoglobinuria is caused by expansion of a hematopoietic stem cell clone with an acquired somatic mutation in the PIG-A gene. This mutation aborts the synthesis and expression of the glycosylphosphatidylinositol anchor proteins CD55 and CD59 on the surface of blood cells, thereby making them more susceptible to complement-mediated damage. A spectrum of disorders occurs in PNH ranging from hemolytic anemia and thrombosis to myelodysplasia, aplastic anemia and, myeloid leukemias. Aplastic anemia is one of the most serious and life-threatening complications of PNH, and a PNH clone is found in almost a third of the cases of aplastic anemia. While allogeneic bone marrow transplantation and T cell immune suppression are effective treatments for aplastic anemia in PNH, these therapies have significant limitations. We report here the first case, to our knowledge, of PNH associated with aplastic anemia treated with the anti-CD20 monoclonal antibody rituximab, which was associated with a significant reduction in the size of the PNH clone and recovery of hematopoiesis. We suggest that this less toxic therapy may have a significant role to play in treatment of PNH associated with aplastic anemia

Iron Overload in Sickle Cell Disease

In sickle cell disease transfusions improve blood flow by reducing the proportion of red cells capable of forming sickle hemoglobin polymer. This limits hemolysis and the endothelial damage that result from high proportions of sickle polymer-containing red cells. Additionally, transfusions are used to increase blood oxygen carrying capacity in sickle cell patients with severe chronic anemia or with severe anemic episodes. Transfusion is well-defined as prophylaxis (stroke) and as therapy (acute chest syndrome and stroke) for major complications of sickle cell disease and has been instituted, based on less conclusive data, for a range of additional complications, such as priapism, vaso-occlusive crises, leg ulcers, pulmonary hypertension, and during complicated pregnancies. The major and unavoidable complication of transfusions in sickle cell disease is iron overload. This paper provides an overview of normal iron metabolism, iron overload in transfused patients with sickle cell disease, patterns of end organ damage, diagnosis, treatment, and prevention of iron overload

Intermediaries of branched chain amino acid metabolism induce fetal hemoglobin, and repress SOX6 and BCL11A, in definitive erythroid cells

High levels of fetal hemoglobin (HbF) can ameliorate human β-globin gene disorders. The short chain fatty acid butyrate is the paradigmatic metabolic intermediary that induces HbF. Inherited disorders of branched-chain amino acid (BCAA) metabolism have been associated with supranormal HbF levels beyond infancy, e.g., propionic acidemia (PA) and methylmalonic acidemia (MMA). We tested intermediaries of BCAA metabolism for their effects on definitive erythropoiesis. Like butyrate, the elevated BCAA intermediaries isovalerate, isobutyrate, and propionate, induce fetal globin gene expression in murine EryD in vitro, are associated with bulk histone H3 hyperacylation, and repress the transcription of key gamma globin regulatory factors, notably BCL11A and SOX6. Metabolic intermediaries that are elevated in Maple Syrup Urine Disease (MSUD) affect none of these processes. Percent HbF and gamma (γ) chain isoforms were also measured in non-anemic, therapeutically optimized subjects with MSUD (Group I, n = 6) or with Isovaleric Acidemia (IVA), MMA, or PA (Group II, n = 5). Mean HbF was 0.24 ± 0.15% in Group I and 0.87 ± 0.13% in Group II (p = .01); only the Gγ isoform was detected. We conclude that a family of biochemically related intermediaries of branched chain amino acid metabolism induces fetal hemoglobin during definitive erythropoiesis, with mechanisms that mirror those so far identified for butyrate