Copy-Number Variation and False Positive Prenatal Screening Results

Abstract

stored at room temperature, 4 platelet concentrates became available routinely in the early 1970s. This allowed for the transfusion of platelets in large quantities, so that the dramatic consequences of bleeding complications were prevented very effec-tively. 5 At the same time, this new platelet support made it possible to increase treatment intensity, which was otherwise limited by hematologic toxic effects (notably thrombocytopenia). Thus, the availability of routine platelet transfusion played an important role in the increased survival among children with ALL. The remarkable efficacy of platelet concentrates in the prevention and treatment of thrombocyto-penia-related bleeding highlights an important aspect of patient blood management: transfusion of the appropriate amount of a blood component, the quality of which is in line with the clinical goal. In children with ALL, this involves the most appropriate correction of defective hemostasis. The treatment of ALL in children is a wonderful story of medical progress from which many les-sons can be learned. Disclosure forms provided by the authors are available with the full text of this letter at NEJM.org. 1. Hunger SP, Mullighan CG. Acute lymphoblastic leukemia in children. N Engl J Med 2015; 373: 1541-52. 2. Gaydos LA, Freireich EJ, Mantel N. The quantitative relation between platelet count and hemorrhage in patients with acute leukemia. N Engl J Med 1962; 266: 905-9. 3. Hersh EM, Bodey GP, Nies BA, Freireich EJ. Causes of death in acute leukemia: a ten-year study of 414 patients from 1954-1963. JAMA 1965; 193: 105-9. 4. Murphy S, Gardner FH. Effect of storage temperature on maintenance of platelet viability — deleterious effect of refriger-ated storage. N Engl J Med1969; 280: 1094-8. 5. Tin AN, Tutzman L, Ohenp D, Untaek IM. Effect of platelet transfusion on hemorrhage in patients with acute leukemia: an autopsy report.