TY - CHAP M1 - Book, Section TI - The Megaloblastic Anemias A1 - Lichtman, Marshall A. A1 - Kaushansky, Kenneth A1 - Kipps, Thomas J. A1 - Prchal, Josef T. A1 - Levi, Marcel M. PY - 2011 T2 - Williams Manual of Hematology, 8e AB - Disorders caused by impaired synthesis of DNA.Prototype is pernicious anemia, a deficiency of vitamin B12 (cobalamin) caused by lack of intrinsic factor, required for its absorption.Characteristics are megaloblastic cells, typically present in the erythroid series as large cells with immature-appearing nuclei but with increasing hemoglobinization of the cytoplasm—often referred to as nuclear-cytoplasmic asynchrony.Megaloblastic granulocytic cells have large size, giant band neutrophils are a feature in the marrow and hypersegmented neutrophils in the marrow and blood. Megakaryocytes may be abnormally large with nuclear abnormalities.Other rapidly dividing tissue cells, such as intestinal epithelium and uterine cervical epithelium may also show cytologic abnormalities. A uterine cervical smear when megaloblastic cytopoiesis is present may be strikingly dysplastic. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/29 UR - hemonc.mhmedical.com/content.aspx?aid=1126651116 ER -