Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038002 (splenomegaly)
 9,873 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In addition to the criteria of the Polycythemia Vera Study Group, positive markers for essential thrombocythemia (ET) include spontaneous BFU-E, splenomegaly, and megakaryocyte morphology in bone marrow smears and biopsy material. The hematologic features of 11 reported cases of ET in childhood showed platelet counts in excess of 1000 x 10(9)/L in all, slight leukocytosis in 8, and splenomegaly in 9. The presenting thrombohemorrhagic manifestations in 8 symptomatic cases were microcirculatory disturbances and transient neurologic ischemic attacks in 2, recurrent mucocutaneous bleedings in 6, and priapism in 1. There are no reports of ET in childhood complicated by microcirculatory disturbances at platelet counts below 1000 x 10(9)/L. Anagrelide and alpha-interferon, which are non-leukemogenic agents for the reduction of platelet counts, may become the treatment of choice in childhood ET. Anagrelide is tolerated better than alpha-interferon. The potential leukemogenic drugs hydroxyurea and busulfan should be used cautiously and withheld as long as possible.
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PMID:Essential thrombocythemia in childhood. 925 10

Polycythemia vera (PV), one of the chronic myeloproliferative disorders (MPD), is characterized by predominant erythroid proliferation and secondary platelet proliferation, and by progression from a proliferative stage to a metastatic phase and finally a malignant phase. These characteristics expose patients to increased risk for thrombohemorrhagic complications, myeloid metaplasia, myelofibrosis, and acute leukemic conversion irrespective of treatments. Currently, there are three agents-hydroxyurea (HU), interferon-alfa (IFN-alpha), and anagrelide-that differ in mechanisms of action and in treating specific phenotypic manifestations of PV, suggesting a potential role for combination therapy. They also differ widely in side effects profiles and severity. Because of the differing risks for long-term complications associated with these agents, age is an important variable in selecting treatments. Patients at high risk for thrombohemorrhagic complications all require cytoreduction, as do patients at intermediate risk who are not effectively managed by phlebotomy and low-dose aspirin. In younger patients, the safest and most effective combination treatment appears to be anagrelide plus IFN-alpha, while in older patients anagrelide plus hydroxyurea may be effective. HU is used sparingly in younger patients because of the long-term increased risk of mutagenicity and possibly leukemogenesis. IFN-alpha is particularly indicated for patients with myeloid metaplasia evidenced by splenomegaly. Anagrelide, which acts on the mature megakaryocyte to prevent platelet budding, is uniquely efficacious in the control of platelet counts.
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PMID:Modern treatment strategies in polycythemia vera. 1268 79