Porth's Essentials of Pathophysiology, 4e

3 Hematopoietic Function

U N I T

11 C h a p t e r

Hematopoietic and Lymphoid Tissues The Bone Marrow and Hematopoiesis Hematopoietic Growth Factors Leukocytes (White Blood Cells) Granulocytes Agranulocytes Leukocyte Developmental Stages Lymphoid Tissues Nonneoplastic Disorders of White Blood Cells Neutropenia (Agranulocytosis) Pathogenesis Clinical Course Infectious Mononucleosis Pathogenesis Clinical Course Neoplastic Disorders of Hematopoietic and Lymphoid Origin Leukemias Classification Etiology and Molecular Biology Acute Leukemias Chronic Leukemias Malignant Lymphomas Non-Hodgkin Lymphomas Hodgkin Lymphoma Plasma Cell Dyscrasias Multiple Myeloma

Disorders of White Blood Cells and Lymphoid Tissues

T

he hematopoietic system and lymphoid tissues are responsible for the generation and regulation of the blood cells that function in the transport of oxy- gen, defense against microorganisms, and preservation of the integrity of the vascular system. This chapter is divided into two parts: the first provides an introduction to the hematopoietic system, lymphoid tissues, and the white blood cells; and the second focuses on disorders of the white blood cells, including those of nonneoplastic (neutropenia and infectious mononucleosis) and neo- plastic (lymphomas, leukemias, and multiple myeloma) origin. The megakaryocytes and platelets are discussed in Chapter 12, the red blood cells in Chapter 13, and the immune system (lymphocytes and monocytes) in Chapter 15.

Hematopoietic and LymphoidTissues

Blood consists of blood cells (i.e., leukocytes or white blood cells, thrombocytes or platelets, and erythrocytes or red blood cells) and the plasma in which the cells are suspended. These cells all derive from a single pool of pluripotent stem cells in the bone marrow, which give rise

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