Among patients with a hyperplastic bone marrow and decreased production of RBCs, one group has an excellent prognosis, and the other is unresponsive, refractory to therapy, and has a relatively poor prognosis. The former includes patients with disorders of relative bone marrow failure due to nutritional deficiency, in whom identification of the etiology and treatment with vitamin B-12, folic acid, or iron leads to a correction of anemia once the appropriate etiology is established. Drugs acting as an antifolic antagonist or inhibitor of DNA synthesis can produce similar effects.
The second group includes patients with an idiopathic hyperplasia that may respond partially to pyridoxine therapy in pharmacologic doses but more frequently does not. These patients have ringed sideroblasts in the bone marrow, indicating an inappropriate use of iron in the mitochondria for heme synthesis.
Certain patients with marrow hyperplasia (see the image below) may have refractory anemia for years, but some of the group eventually develop acute myelogenous leukemia.
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Anemia. Decreased production of red blood cells is suggested in certain patients with anemia. Bone marrow biopsy specimen allows categorization of patients with anemia without evidence of blood loss or hemolysis into 3 groups: aplastic or hypoplastic disorder, hyperplastic disorder, or infiltration disorder. Each category and its associated causes are listed in this image.
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Microcytic anemia.
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Peripheral smear showing classic spherocytes with loss of central pallor in the erythrocytes.
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Bone marrow aspirate containing increased numbers of plasma cells.
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Bone marrow aspirate showing erythroid hyperplasia and many binucleated erythroid precursors.