The white pulp (lymphoid tissue) functions in antigen processing and antibody production.
The red pulp (monocyte-macrophage system) serves as a filter, retaining defective blood cells and foreign particles.
Hypersplenism is considered “appropriate” if it is an exaggeration of normal function, as in hereditary spherocytosis or idiopathic thrombocytopenic purpura, or “inappropriate” if the hyperfunction is a result of vascular congestion or infiltrative disease.
It is usually associated with splenomegaly.
It causes cytopenias with associated compensatory bone marrow hyperplasia.
It usually is corrected by splenectomy, if indicated.
Table 26–1 lists the causes of hypersplenism. Table 26–2 lists the causes of massive splenomegaly.
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