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)

A 40-year-old male patient presented with leukocytosis and mild splenomegaly. Bone marrow aspirate showed myeloid hyperplasia and eosinophilia resembling chronic myelogenous leukemia in the chronic phase. Cytogenetic examination of bone marrow cells revealed an unusual karyotype, t(8;13)(p11;q12), in 20/20 metaphases. Not the BCR/ABL, but the ZNF198/FGFR1 chimeric mRNA was detected by reverse transcription-polymerase chain reaction. Since 1992, 12 patients with a similar atypical myeloproliferative disorder with T-cell non-Hodgkin's lymphoma or eosinophilia, associated with a t(8;13) translocation in both bone marrow and lymph node specimens, have been described. The present case is an additional one that should be classified into this new clinicopathologic entity.
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PMID:A chronic myelogenous leukemia-like myeloproliferative disorder accompanied by T-cell lymphoblastic lymphoma with chromosome translocation t(8;13)(p11;q12): a Japanese case. 1064 54

The term 'erythrocytosis' has advantages over 'polycythaemia' to describe patients with a raised haematocrit (PCV) and deserves to be more widely used. Measurement of red cell mass (RCM) and its relation to that expected for an individual's height and weight permits initial subdivision of erythrocytosis into absolute (increased RCM) or apparent normal RCM. Absolute erythrocytosis may be primary (intrinsically abnormal marrow erythropoiesis) or secondary (increased erythropoietin drive in response to pathological events outside the bone marrow). Both primary and secondary erythrocytosis may be either congenital or acquired. Idiopathic erythrocytosis is a third, probably heterogenous, group within the absolute erythrocytoses. Familial abnormalities of the erythropoietin receptor underlie the primary congenital subgroup. Polycythaemia vera (PV), the clonal myeloproliferative disorder, is so far, the only primary acquired disorder. Newer diagnostic investigations such as serum erythropoietin estimation, improved karyotypic analysis, in vitro culture of erythroid colonies and estimation of spleen size before splenomegaly is palpable, have permitted some modification of the traditional diagnostic criteria of polycythaemia vera. This may allow more confident diagnosis and, together with improved testing for causes of secondary erythrocytosis, may reduce the number of patients so far unsatisfactorily consigned to the idiopathic erythrocytosis group.
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PMID:The classification and diagnostic criteria of the erythrocytoses (polycythaemias) 1079 8

Idiopathic myelofibrosis (IMF) is a chronic myeloproliferative disorder characterized by fibrosis of the bone marrow, varying degrees of extramedullary hematopoiesis, splenomegaly, anemia, and a leukoerythroblastic peripheral blood smear. Bone marrow fibrosis develops as a secondary phenomenon and is caused by increased intramedullary activity of mitogens such as platelet-derived growth factor (PDGF), transforming growth factor-beta (TGF-beta), basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), and calmodulin. Because of the variable clinical course of IMF, attempts have been made to define prognostic parameters that can be helpful in detecting patients with a shortened life expectancy. The most important adverse prognostic parameters that have been reported are hemoglobin concentration, age, leukocyte count, number of thrombocytes, and cytogenetic abnormalities. However, no standardized prognostic score for IMF has yet been established. Therapeutic strategies in IMF remain predominantly supportive. The most common are blood transfusions, androgens, and cytoreductive agents such as hydroxyurea. Bone marrow transplantation is increasingly being taken into consideration, but it still has to be regarded as an experimental approach. Interferon-alpha (IFN-alpha) has shown promising results in early hyperproliferative stages of IMF but has no or only very little effect in more advanced stages of the disease. Whether IFN-alpha is able to postpone marrow fibrosis if administered in early disease stages remains to be determined in future clinical trials.
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PMID:The role of interferon-alpha in the treatment of idiopathic myelofibrosis. 1113 27

The present study describes clinicopathological criteria to distinguish the 5 sequential stages proposed by Wasserman et al in the natural history of newly diagnosed PV patients. The European Working Group on MPD (EWG.MPD) extended and modified the PVSG diagnostic criteria of PV by including bone marrow histopathology. From the results of prospective randomized studies in PV it became evident that new clinical trials in previously untreated PV patients should focus on comparing interferon-alpha, a non-leukemogenic approach, versus a potential leukemogenic myelosuppressive treatment modality. Hydroxyurea appears to be the least leukemogenic myelosuppressive agent in long-term prospective clinical PV-studies extending observation periods of more than 10 years. The rational for using IFN-alpha as a first-line treatment option in newly diagnosed PV-patient include its effectiveness to abate constitutional symptoms and to induce a complete remission thereby avoiding phlebotomy, iron deficiency, and macrocytosis associated with hydroxyurea. Moreover IFN-alpha may prevent or delay the development of postpolycythemic myelofibrosis if used early in the course of the disease. Clinicians will be reluctant to postpone the use of hydroxyurea in early stage PV as long as a conservative approach using phlebotomy aiming at a hematocrit below 0.45, plus low-dose aspirin for the control platelet function or anagrelide for the control platelet number is used to keep the patient healthy. Low-dose aspirin will prevent the microvascular thrombotic complications of thrombocythemia associated with PV in remission after phlebotomy, but lacks myelosuppressive activity. Control of megakaryocyte maturation and reduction of platelet production to normal (<400 x 10(9)/l) by relatively low doses of anagrelide will predict a significant reduction of vascular complications in the early stages of PV, may prevent progression to myelofibrosis during follow-up of PV and very probable will postpone the use of hydroxyurea treatment for controlling the platelet count in PV. Large scale randomized clinical trials in PV are proposed, which should aim not only for clinical and hematological response, safety, efficacy, but should also assess toxicity, the need for phlebotomy and whether the development of progressive disease such as splenomegaly, pruritus, myelofibrotic myeloid metaplasia, spent phase, myelodysplasia and acute leukemia can be delayed or prevented by IFN-alpha as compared to a conservative approach of phlebotomy plus low-dose aspirin or anagrelide followed by hydroxyurea when signs of myeloproliferative activity became evident.
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PMID:Diagnosis and treatment of polycythemia vera and possible future study designs of the PVSG. 1067 96

The t(5;12)(q33;p13) translocation associated with chronic myelomonocytic leukemia (CMML) generates a TEL/PDGFbetaR fusion gene. Here, we used a murine bone marrow transplant (BMT) assay to test the transforming properties of TEL/PDGFbetaR in vivo. TEL/PDGFbetaR, introduced into whole bone marrow by retroviral transduction, caused a rapidly fatal myeloproliferative disease that closely recapitulated human CMML. TEL/PDGFbetaR transplanted mice developed leukocytosis with Gr-1(+) granulocytes, splenomegaly, evidence of extramedullary hematopoiesis, and bone marrow fibrosis, but no lymphoproliferative disease. We assayed mutant forms of the TEL/PDGFbetaR fusion protein - including 8 tyrosine to phenylalanine substitutions at phosphorylated PDGFbetaR sites to which various SH2 domain-containing signaling intermediates bind - for ability to transform hematopoietic cells. All of the phenylalanine (F-) mutants tested conferred IL-3-independence to a cultured murine hematopoietic cell line, but, in the BMT assay, different F-mutants displayed distinct transforming properties. In transplanted animals, tyrosines 579/581 proved critical for the development of myeloproliferative phenotype. F-mutants with these residues mutated showed no sign of myeloproliferation but instead developed T-cell lymphomas. In summary, TEL/PDGFbetaR is necessary and sufficient to induce a myeloproliferative disease in a murine BMT model, and PDGFbetaR residues Y579/581 are required for this phenotype.
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PMID:Fatal myeloproliferation, induced in mice by TEL/PDGFbetaR expression, depends on PDGFbetaR tyrosines 579/581. 1068 70

Low-risk essential thrombocythemia patients include patients aged 18 to < 80 years with no vascular risk factor or previous thrombosis, no associated disease, a normal life expectancy, and a platelet count between 400 and 1,000 x 10(9)/L up to 1,500 x 10(9)/L. Asymptomatic essential thrombocythemia patients may be at risk for microvascular circulation disturbances. The indication for low-dose aspirin in asymptomatic essential thrombocythemia patients is uncertain, therefore randomization for aspirin 50 mg versus placebo is recommended. Symptomatic essential thrombocythemia patients with erythromelalgia and its ischemic complications, atypical transient ischemic attacks, minor stroke, visual disturbances and "superficial thrombophlebitis" in the absence of bleeding, vascular risk factors, or vascular disease have a clear indication for aspirin in a regular dose. To determine whether 50 mg/day is as effective as 100 mg/day for the prophylaxis of microvascular circulation disturbances in essential thrombocythemia, a randomized trial comparing low-dose aspirin 50 mg versus 100 mg at platelet counts between 400 and 1,000 up to 1,500 x 10(9)/L is recommended. To address the question whether reduction of the platelet count to normal (< 350 x 10(9)/L) is as effective as low-dose aspirin for the long-term relief of microvascular circulation disturbances, a randomized study comparing low-dose aspirin with the correction of platelet count to normal by anagrelide is recommended. High-risk essential thrombocythemia patients have a clear indication for platelet reductive therapy, including: (a) platelets > 1,500 x 10(9)/L, history of major thrombosis (myocardial infarction, stroke, peripheral occlusive vascular disease), or presence of vascular disease (e.g., arteriosclerosis); (b) history or presence of spontaneous or major bleedings, bleedings elicited by low-dose aspirin for the secondary prevention of vascular complications in essential thrombocythemia at platelet counts < 1500 x 10(9)/L, and side effects of long-term aspirin treatment such as gastritis; and progression from low- to high-risk essential thrombocythemia patients during follow-up or progressive myeloproliferative disease such as significant splenomegaly, myelofibrosis, leukocytosis, etc. To address the question of optimal treatment of high-risk essential thrombocythemia patients, randomization for anagrelide versus interferon at < 65 years of age and anagrelide versus hydroxyurea at an age > 65 years is recommended.
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PMID:Aspirin and platelet-lowering agents for the prevention of vascular complications in essential thrombocythemia. 1072 22

Interferon alpha (IFN) inhibits the growth of the abnormal clone in patients with myeloproliferative disorders, leading to a reduction of the clinical and laboratory signs of the pathologic myeloproliferation. The therapeutic efficacy of IFN in polycythemia vera (PV) is demonstrated by the summarized treatment results of 279 patients participating in 16 prospective nonrandomized studies and in three case reports. The initial IFN dose ranged from 3 to 35 million IU/week. In 82% of the patients the frequency of phlebotomies was reduced. In 50% a complete remission was achieved, defined as a stable hematocrit of 45% without concomitant phlebotomies. Reduction of splenomegaly was seen in 77% and control of pruritus in 81% of the patients. The median observation time of the studies was 13 months (ranging from 3 to 84 months). Individual cases were followed for up to 126 months. In 21% of the patients IFN was terminated, owing mostly to side effects. The selective suppression of the malignant clone by IFN was demonstrated by the induction of cytogenetic remissions in sporadic cases with a chromosomal marker and by the observation of unmaintained remissions that lasted up to 4.8 years. IFN has no known mutagenic or teratogenic effects. The data presently available demonstrate that IFN is an effective alternative to the present forms of treatment in PV. Controlled prospective studies are essential to clarify whether the favorable biologic properties are also reflected by a benefit in clinical course and survival, and whether IFN may reduce the rates of acute leukemia and myelofibrosis. A randomized study that compares IFN and hydroxyurea in patients with PV has recently been initiated by the Suddeutsche Hamoblastosegruppe (SHG) in Germany.
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PMID:Interferon alpha in the treatment of polycythemia vera. 1080 30

The diagnosis of an essential thrombocytosis is demonstrated in this presentation of a well-looking 53 year old man who had a five-year history of increasing facial asymmetry as evidenced by deviation of his mandible to the right and malocclusion. The enlarged mandibular condyle was the first manifestation of his underlying myeloproliferative disorder. His management will be discussed. Neoplastic diseases of the multipotent haematopoietic stem cells result in four major diseases: chronic myelogenous leukaemia (CML); polycythaemia vera (PV); agnogenic myeloid metaplasia with myelofibrosis (AMM/MF); essential thrombocytosis (ET). CML: demonstrates increased production of neutrophils and marked splenomegaly. It is divided into a chronic phrase typified by hyperplasia of mature bone marrow elements and a blastic or acute phase which evolves into a proliferation of immature marrow elements and can develop into acute myelogenous leukaemia. PV: associated with increased production of all myeloid cells but dominated by increased red blood cells with splenomegaly. AMM/MF: allows the neoplastic stem cells to proliferate and lodge in multiple sites outside the bone marrow. Splenomegaly and fibrosis of marrow spaces also occurs. ET: resulting in a markedly elevated platelet count in the absence of a recognizable stimulus. Treatment revolves around measures to maintain hydration, to relieve arthralgias, to prevent thrombotic episodes, and to prevent infections.
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PMID:A review of myeloproliferative disease with presentation in the head and neck region. 1089 23

Thrombocytosis is a common feature of myeloproliferative disorders but may also result from various conditions including chronic iron deficiency, hemorrhage, chronic inflammation and splenectomy. We report two cases of secondary thrombocytosis caused by isolated and congenital asplenia, mimicking essential thrombocythemia. These two adult cases of spleen agenesis were unexpected. We conclude that in thrombocytosis without clinical evidence of splenomegaly, attentive screening of blood in search of Howell-Jolly bodies and abdominal ultrasonography should always be performed not only to detect mild spleen enlargement but also to make sure of the presence of this organ.
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PMID:Isolated spleen agenesis: a rare cause of thrombocytosis mimicking essential thrombocythemia. 1106 71

It has been suggested that HIV plays a role in the generation of myeloproliferative disorders, including polycythemia vera (PV). Seven cases of polycythemia in HIV patients have been described in the literature, but only 3 of these met criteria for determining a primary origin (vera) of polycythemia. We report a case of PV in a patient infected with HIV. A 45 year old non-smoking homosexual male presented with 15.7 g/dl hemoglobin in 1991, and was diagnosed with HIV. After 7 years, he presented with plethora, splenomegaly, an erythrocyte mass of 71 ml/kg, and an oxygen saturation of 93.9% (the latter three constituting the major criteria for the diagnosis of PV). Erythrocytes 7.35 x 10(6)/ml hemoglobin, 21.4 g/dl, hematocrit 63%, leukocytes 12,400, erythropoietin < 5 nmoll/ml. These values are all compatible with a diagnosis of PV. The CD4 count was 321 cells/mm(3) and HIV viral load was undetectable. The patient was initially treated with zidovudine. He was then treated with didanosine, lamivudine, and saquinavir, but all of them failed to slow the increase in erythrocyte levels. After a diagnosis of PV, he was treated with hydroxyurea and phlebotomy, which normalized the hemogram. CD4 count rose to 474 cells/mm(3) and HIV viral load remained at undetectable levels. The patient remains in stable condition with combination treatment after 1 year. We suggest that this is a case of HIV infection which may have led to the emergence of polycythemia vera. Treatment of the HIV did not prevent the appearance of the myeloproliferative disorder.
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PMID:Polycythemia vera in a patient with the human immunodeficiency virus: a case report. 1118 68


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