The use of haemopoietic growth factors in blood disorders

Growth factors and their impact on transfusion medicine

Hematopoietic growth factors, glycoproteins that stimulate self-renewal, differentiation, and proliferation of responsive hematopoietic cells, promise to revolutionize transfusion medicine. Recombinant DNA technology has made several of these cytokines available at pharmacologic doses, and new candidate agents for clinical application appear regularly. Growth factors prescribed for patients have already reduced the requirement for red blood cell and granulocyte transfusions in selected clinical circumstances. A lineage-specific thrombopoietin will likely limit the need for platelet transfusions. Hematopoietic cytokine injections have also been used to increase the number of red blood cells, granulocytes and circulating primitive progenitor cells in blood donors. Cytokine-stimulated peripheral blood progenitor cell infusions have complemented and, in some instances, replaced bone marrow for adjunctive cancer chemotherapy and for bone marrow transplantation. Finally, synergistic combinations of cytokines can effect ex vivo expansion of lymphocytes and of progenitor cells to provide novel blood components. Hematopoietic growth factors are still expensive and their long-term effects remain to be determined. However, as the biologic activities of cytokines and the physiology of hematopoietic progenitor cells become better understood, the clinical application of novel cellular components may redefine the concept of blood transfusion.

Dominantly inherited severe congenital neutropenia

We report a family with autosomal dominant inherited neutropenia, characterized by maturation arrest of neutrophil precursors and hypergammaglobulinaemia. A mother, two children by her first marriage and two by her second were affected. They suffered recurrent lung, skin, ear and periodontal infections. Four have had appendicitis, and three mastoiditis. One died at 7 years from neutropenic enterocolitis, and a second at 10 years from small bowel infarction. Four who were treated with rhG-CSF responded to 5-14 micrograms/kg/day with normal neutrophil counts. Daily therapy has maintained neutrophil counts above 1000 x 10(9) per litre. Elective appendicectomy and long term G-CSF therapy are indicated.