Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0032463 (polycythemia vera)
 3,374 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A woman with an eight-year history of polycythemia vera presented with numbness and weakness of both legs. A large spinal haematoma was revealed on magnetic resonance imaging which was treated clinically and which subsequently resolved.
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PMID:Spinal cord compression by spontaneous spinal subdural haematoma in polycythemia vera. 764 7

A 10.5-year-old, castrated male shih tzu was presented for evaluation of weakness, pica, and pallor of the mucous membranes. A hemogram indicated an inflammatory leukogram and a regenerative anemia with spherocytosis and thrombocytosis. The dog responded well to conservative therapy for immune-mediated hemolytic anemia (IMHA). However, the thrombocytosis did not resolve. Serial hemograms were characterized by persistent thrombocytosis (platelet count, 577,000 to 1,200,000/microl) with abnormal platelet morphology. A systematic investigation ruled out causes of physiological and reactive thrombocytoses. A diagnosis of essential thrombocythemia was made by fulfilling the criteria of the Polycythemia Vera Study Group of the National Cancer Institute. The marked thrombocytosis was nonresponsive to hydroxyurea therapy. The dog remains healthy despite the marked increase in the number of circulating platelets. A review of causes of thrombocytoses in humans and animals is presented, and the criteria for diagnosis of essential thrombocythemia are examined.
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PMID:Essential thrombocythemia in a dog: case report and literature review. 959 Apr 46

A 40-year-old Xhosa male presented with progressive upper lumbar back pain and weakness At examination he was emaciated and had enlarged lymph nodes in the groin and axilla. Both lower limbs were severely atrophic and weak. Sensation to touch and pain was decreased below L3 bilaterally. MR of the spine showed a discrete, contrast-enhancing epidural mass. A T10-T12 laminectomy revealed an soft, vascular extradural tumor dorsal to the cord. The mass was loosely applied to the dura and easy to remove. The operative specimen consisted of a sausage-shaped (3.5 x 2.0 x 1.2 cm), thinly-encapsulated mass of reddish-brown tissue. The cut surface had a mottled, vaguely nodular, yellowish-brown appearance. Microscopic examination revealed sheets of hematopoeitic elements, including myeloid, red cell and megakaryocytic lines, the latter showing Factor 8-related positivity. The final diagnosis was extramedullary hematopoiesis (EMH). A bone marrow biopsy performed as a result of the diagnosis showed a myeloproliferative disease and polycythemia vera. EMH in the spinal epidural space is a rare but treatable cause of progressive paraparesis in patients with a variety of hematological disorders. Since 1956 there have been more than 50 reported cases, most of which occurred in association with thalassaemia. In spinal cord compression secondary to EMH, the lesions are commonly localized to the mid-lower thoracic region.
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PMID:October 2001: 40-year-old Xhosa male with back pain and leg weakness. 1195 81

Essential thrombocythemia and polycythemia vera are both chronic progressive myeloproliferative disorders of insidious onset. If the excessive production of red cells and/or platelets is controlled, patients with these disorders may have prolonged survival. However, the clinical course of these patients can be complicated by a variety of events, including thrombotic episodes, bleeding episodes, arthropathies, pruritus, weakness, weight loss, neurologic impairment, erythromelalgia, fever, abdominal pain, and the life-threatening consequences of progression to myelofibrosis and/or acute leukemia. Effective control of hematopoiesis by phlebotomy or a variety of therapeutic agents has resulted in a reduction or elimination of many of these clinical events, but has not altered the evolution to myelofibrosis or acute leukemia. Use of each of these therapeutic strategies is also associated with a range of adverse events. Monitoring overall survival or a reduction in the frequency of clinical events has previously served as a means of assessing the results of these therapeutic interventions. Quality-of-life instruments have not been applied in a systematic fashion to the evaluation of outcomes in patients with these chronic myeloproliferative disorders. Quality-of-life assessments evaluate not only the state of well-being of a patient that results from an assessment of the individual's ability to perform everyday activities, which are reflective of physical, psychological, and social well-being, but also patient satisfaction with the control of disease and/or treatment-related symptoms. Quality-of-life instruments have been used to assess the clinical course of patients suffering from a variety of disorders, ranging from cancer to renal failure to chronic fatigue syndrome. Information about quality-of-life outcomes can contribute to the evaluation of variations in dose and timing of administration of therapeutic agents. It is possible that the side effects of a particular therapy may outweigh the disease regression achieved with a particular therapy. In the future, quality-of-life instruments may prove useful in prospectively evaluating therapeutic end points in patients with essential thrombocythemia and polycythemia vera.
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PMID:Quality of life issues in patients with essential thrombocythemia and polycythemia vera. 1209 51

Dermatomyositis (DM) is a unique inflammatory myopathy with clinical findings of proximal muscle weakness, characteristic rash, and elevated muscle enzymes. The association of DM and malignancy, most commonly adenocarcinoma, is well known. There have been few case reports of primary myelofibrosis associated with DM. We present the case of a 69-year-old male with a history of polycythemia vera (PV) who developed proximal muscle weakness, dysphagia, and rash. He was found to have elevated creatinine kinase and skin biopsy was consistent with DM. Due to persistent pancytopenia a bone marrow biopsy was performed and showed postpolycythemic myelofibrosis. To our knowledge, this is the first case reported of this unique association.
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PMID:Dermatomyositis Associated with Myelofibrosis following Polycythemia Vera. 2866 85

The major weakness of most knock-in JAK2V617F mouse models is the presence of the JAK2 mutation in all rather than in a few hematopoietic stem cells (HSC), such as in human "early-stage" myeloproliferative neoplasms (MPN). Understanding the mechanisms of disease initiation is critical as underscored by the incidence of clonal hematopoiesis of indeterminate potential associated with JAK2V617F. Currently, such studies require competitive transplantation. Here, we report a mouse model obtained by crossing JAK2V617F/WT knock-in mice with PF4iCre transgenic mice. As expected, PF4iCre;JAK2V617F/WT mice developed an early thrombocytosis resulting from the expression of JAK2V617F in the megakaryocytes. However, these mice then developed a polycythemia vera-like phenotype at 10 weeks of age. Using mT/mG reporter mice, we demonstrated that Cre recombination was present in all hematopoietic compartments, including in a low number of HSC. The frequency of mutated cells increased along hematopoietic differentiation mimicking the clonal expansion observed in essential thrombocythemia and polycythemia vera patients. This model thus mimics the HSC compartment observed in early-stage MPN, with a small number of JAK2V617F HSC competing with a majority of JAK2WT HSC. PF4iCre;JAK2V617F/WT mice are a promising tool to investigate the mechanisms that regulate clonal dominance and progression to myelofibrosis.
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PMID:Description of a knock-in mouse model of JAK2V617F MPN emerging from a minority of mutated hematopoietic stem cells. 3169 34

Ruxolitinib is a highly potent JAK2 inhibitor approved for the treatment of myelofibrosis (idiopathic or post-polycythemia vera or post-essential thrombocythemia) and, more recently, for polycythemia vera with an inadequate response to or intolerant of hydroxyurea. The most common adverse events of ruxolitinib include immunosuppression with an increased risk of reactivation of silent infections and increased non-melanoma skin cancer. The known neurological side effects of ruxolitinib are dizziness and headache, but no neurological paroxysmal episodes have been recorded. This report deals with an 80-year-old outpatient woman with polycythemia vera turned into myelofibrosis who experienced neurological episodes of hypoesthesia and weakness of right arm and leg during ruxolitinib treatment.
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PMID:Unexpected Neurological Symptoms of Ruxolitinib: A Case Report. 3322 94