One of the spleen's major functions is to remove blood cells from the body's bloodstream. In cases of hypersplenism, this normal function accelerates, and the spleen begins to automatically remove cells that may still be normal in function. Hypersplenism may occur as a primary disease (brought on by a problem within the spleen itself), leading to other complications, or as a secondary disease, resulting from an underlying disease or disorder.
Secondary hypersplenism results from another disease such as chronic malaria, rheumatoid arthritis, tuberculosis, or polycythemia vera, a blood disorder. Spleen disorders in general are almost always secondary in nature. Hypersplenism may also be caused by tumors.
Symptoms include easy bruising, easy contracting of bacterial diseases, fever, weakness, heart palpitations, and ulcerations of the mouth, legs and feet. Individuals may also bleed unexpectedly and heavily from the nose or other mucous membranes, and from the gastrointestinal or urinary tracts. Most patients will develop an enlarged spleen, anemia, leukopenia, or abnormally low white blood cell counts, or thrombocytopenia, a deficiency of circulating platelets in the blood. Other symptoms may be present that reflect the underlying disease that has caused hypersplenism.
Diagnosis of hypersplenism begins with review of symptoms and patient history, and careful feeling palpation of the spleen. Sometimes, a physician can feel an enlarged spleen. X-ray studies, such as ultrasound and computed tomography scan (CT scan), may help diagnose an enlarged spleen and possible underlying causes, such as tumors. Blood tests indicate decreases in white blood cells, red blood cells, or platelets. Another test measures red blood cells in the liver and spleen after injection of a radioactive substance, and indicates areas where the spleen is holding on to large numbers of red cells or is destroying them.
In cases of secondary hypersplenism, the underlying disease must be treated to prevent further sequestration or destruction of blood cells, and possible spleen enlargement. Those therapies will be tried prior to removal of the spleen (splenectomy), which is avoided if possible. In severe cases, the spleen must be removed. Splenectomy will correct the effects of low blood cell concentrations in the blood.
Prognosis depends on the underlying cause and progression of the disease.
Left untreated, spleen enlargement can lead to serious complications. Hypersplenism can also lead to complications due to decreased blood cell counts.