In some patients the bone marrow eventually becomes

In some patients, the bone marrow eventually becomes fibrotic, hematopoiesis develops
in the spleen, and anemia follows. In a few patients, acute myeloblastic leukemia
develops in the later stages, especially if treatment has involved chemotherapy.

9/26/18, 5*38 PM
Page 61 of 74
Etiology
Primary polycythemia is a neoplastic disorder of unknown origin that commonly
develops between the ages of 40 and 60 years, although younger individuals can be
affected. Secondary polycythemia may be a compensation mechanism intended to
provide increased oxygen transport in the presence of chronic lung disease or heart
disease or from living at high altitudes. Some cases result from erythropoietin-secreting
tumors such as renal carcinoma.
Signs and Symptoms
The patient appears plethoric plethoric and cyanotic cyanotic, with the deep bluish-red tone of the skin
and mucosa resulting from the engorged blood vessels and sluggish blood flow.
Hepatomegaly Hepatomegaly , an enlarged liver, and splenomegaly are present. Pruritus is common.
Blood pressure increases, the pulse is full and bounding, and dyspnea, headaches, or
visual disturbances are common. Thromboses and infarctions may affect the extremities,
liver, or kidneys as well as the brain or the heart. Congestive heart failure frequently
develops because of the increased work load resulting from the increased volume and
viscosity of blood. High levels of uric acid resulting from cell destruction result in severe
joint pain.
Diagnostic Tests
Cell counts are increased, as are hemoglobin values, and hematocrit is elevated. In
polycythemia vera, the malignant or abnormal cell is the erythrocyte. Bone marrow is
hypercellular, with the red marrow replacing some fatty marrow. Hyperuricemia is
present because of the high cell destruction rate.

9/26/18, 5*38 PM
Page 62 of 74
PRINTED BY: [email protected] Printing is for personal, private use only. No part of this book may be
reproduced or transmitted without publisher's prior permission. Violators will be prosecuted.
Treatment
Drugs or radiation may be used to suppress the activity of the bone marrow. There is
significant risk that fibrosis or leukemia may develop with these methods. Periodic
phlebotomy phlebotomy , or removal of blood, may be used to minimize the possibility of
thromboses or hemorrhages.
10-8 Think about
Compare the general effects of anemia and polycythemia in terms of hemoglobin level,
hematocrit, general appearance, and possible complications.
The Leukemias
The leukemias are a group of neoplastic disorders involving the white blood cells. The
estimated number of new cases of leukemia each year is 31,000 including 2500 children.