Hypersplenism is a syndrome characterized by splenomegaly and any or all of the following cytopenias: anemia, leukopenia, or thrombocytopenia. Implicit in the definition is that the cytopenias will correct following splenectomy.
The hypersplenism usually is the result of an identifiable pathologic process, but rarely, the cause of the splenomegaly remains elusive, and the hypersplenism is termed primary
In hypersplenism, the thrombocytopenia is moderately severe (platelet counts of 50 X 109/L to 150 X 109/L). Severe thrombocytopenia (less than 20 ? 109/L) suggests another diagnosis. Therefore, it is unusual for patients with hypersplenism to have evidence of hemostatic impairment attributable to thrombocytopenia, or to need specific interventions to raise the platelet count.
Thrombocytopenia is likely to be caused by hypersplenism when (a) splenomegaly is present, (b) the thrombocytopenia is mild to moderate in severity, (c) moderately reduced neutrophil and low-normal hemoglobin levels are found, and (d) no or minimal evidence for impaired hematopoiesis is observed on bone marrow examination