HEMATOLOGY

Important advances in hematology during the past year concern the use of folic acid in anemia and further trial of radioactive isotopes and other new chemicals in the treatment of leukemia and polycythemia. The therapeutic application of folic acid has reemphasized also the need for an accurate laboratory study and classification of the anemias before treatment is begun, since this drug is indicated only with macrocytosis. FOLIC ACID Synthetic folic acid (pteroylglutamic acid) is now available in unlimited quantities. It is of value only in a macrocytic anemia with a megaloblastic bone marrow. Important examples of such an anemia are (1) idiopathic pernicious anemia, when there is deficient formation of a specific erythrocyte-maturing factor (EMF); (2) macrocytic nutritional anemia in children due to a defect in supply or absorption, the macrocytic anemia of pregnancy due to increased need and the macrocytic anemia of adults dependent on a defective absorption of