Sickle-Cell Disease

Abstract

It is now recognized that bone-marrow failure rather than hyperhemolysis underlies the crises in sickle-cell disease.^1,2Bonemarrow failure has been reported in Cooley's hemolytic anemia,³hereditary spherocytosis,⁴and paroxysmal nocturnal hemoglobinuria.⁵Maturation arrest of the neutrophil polymorphonuclear leukocytes has been noted in sickle-cell disease.⁶Infection has been thought to precipitate bone-marrow aplasia in sickle-cell disease^1,2and in hereditary spherocytosis.⁷The occurrence of "aplastic crisis" in several members of a family has been recorded in hereditary spherocytosis⁷and in sickle-cell disease.¹⁷Erythroblastopenia has been noted during the course of viral pneumonia in patients without hemolytic blood diseases,⁸and the same communication records eosinophilia in patients who had erythrocytic aplasia after exposure to allergens. The association of chronic hemolytic anemias with megaloblastic arrest of the bone marrow has been documented. Some of these responded to vitamin B₁₂therapy,⁹some were associated with pregnancy,¹⁰and in others dietary deficiency of folie acid