Search results for "essential thrombocythemia"
showing 10 items of 38 documents
Cumulative visual impact of two coagulability disorders: A case report.
2020
Cumulative visual impact of two coagulability disorders were reviewed by presenting a case of a young female patient with a spontaneous abortion and two thromboembolic events in 8 years, whose visual function was severely affected. The particularities of her genetic constellation regarding the retinal circulation are also discussed. The patient developed a central retinal artery occlusion in the right eye during pregnancy in 2010, which led to an extended hematological workup that revealed presence of MTHFR C677T and MTHFR A1298C heterozygote mutations. The screening for myeloproliferative disorders showed JAK2 V617F gene mutation. Test results confirmed the diagnosis of thrombophilia and e…
A conditional inducible JAK2V617F transgenic mouse model reveals myeloproliferative disease that is reversible upon switching off transgene expressio…
2019
Aberrant activation of the JAK/STAT pathway is thought to be the critical event in the pathogenesis of the chronic myeloproliferative neoplasms, polycythemia vera, essential thrombocythemia and primary myelofibrosis. The most frequent genetic alteration in these pathologies is the activating JAK2V617F mutation, and expression of the mutant gene in mouse models was shown to cause a phenotype resembling the human diseases. Given the body of genetic evidence, it has come as a sobering finding that JAK inhibitor therapy only modestly suppresses the JAK2V617F allele burden, despite showing clear benefits in terms of reducing splenomegaly and constitutional symptoms in patients. To gain a better …
Clinical Features And Course Of Refractory Anemia With Ring Sideroblasts Associated With Marked Thrombocytosis
2012
Background Refractory anemia with ring sideroblasts associated with marked thrombocytosis was proposed as a provisional entity in the 2001 World Health Organization classification of myeloid neoplasms and also in the 2008 version, but its existence as a single entity is contested. We wish to define the clinical features of this rare myelodysplastic/myeloproliferative neoplasm and to compare its clinical outcome with that of refractory anemia with ring sideroblasts and essential thrombocythemia. Design and Methods We conducted a collaborative retrospective study across Europe. Our database included 200 patients diagnosed with refractory anemia with ring sideroblasts and marked thrombocytosis…
Essential thrombocythemia or chronic idiopathic myelofibrosis? A single-center study based on hematopoietic bone marrow histology.
2006
We reviewed a large series of patients with essential thrombocythemia diagnosed on the basis of the Polycythemia Vera Study Group criteria, and reclassified them by evaluating their major morphologic features and clinical course using the World Health Organization classification. The morphologic review of the bone marrow biopsies of 116 patients (44 males and 72 females; aged 19 - 83 years, median 55 years; median follow-up 121 months) led to 22 cases (19%) being classified as essential thrombocythemia (ET), 24 (21%) as chronic idiopathic myelofibrosis (CIMF)-0, 44 (37%) as CIMF-1, 13 (12%) as CIMF-2, 9 (8%) as latent phase polycythemia vera, and four (3%) as chronic myeloproliferative diso…
Different immunophenotypical apoptotic profiles characterise megakaryocytes of essential thrombocythaemia and primary myelofibrosis.
2009
Aims: Essential thrombocythaemia (ET) and primary myelofibrosis (PMF) share some clinical and pathological features, but show different biological behaviour and prognosis. The latest contributions to understanding the nature of these disorders have focused on bone marrow microenvironment remodelling and proliferative stress, recognising megakaryocytes (MKCs) as “key-cells”. The aim of this study was to investigate the apoptotic profile of ET and PMF MKCs in order to further characterise the biology of these disorders. Methods: Bone marrow biopsy samples from 30 patients with ET, and 30 patients with PMF, were immunophenotypically studied for the expression of pro-apoptotic (Fas, Fas-L, Bax,…
Calreticulin Mutations in Myeloproliferative Neoplasms: Comparison of Three Diagnostic Methods
2015
International audience; Calreticulin (CALR) mutations have recently been reported in 70-84% of JAK2V617F-negative myeloproliferative neoplasms (MPN), and this detection has become necessary to improve the diagnosis of MPN. In a large single-centre cohort of 298 patients suffering from Essential Thrombocythemia (ET), the JAK2V617F, CALR and MPL mutations were noted in 179 (60%), 56 (18.5%) and 13 (4.5%) respectively. For the detection of the CALR mutations, three methods were compared in parallel: high-resolution melting-curve analysis (HRM), product-sizing analysis and Sanger sequencing. The sensitivity for the HRM, product-sizing analysis and Sanger sequencing was 96.4%, 98.2% and 89.3% re…
Evidence of jak2 val617phe positive essential thrombocythemia with splanchnic thrombosis during estroprogestinic treatment
2008
The discovery of the Janus kinase 2 Val617Phe mutation has brought new insights into the development of myeloproliferative disorders; however, the pathogenesis of essential thrombocythemia and its related thrombotic complications has not been completely understood. Although the Janus kinase 2 Val617Phe mutation confirms the initially suspected clonal character of the disease, factors influencing clonal transformation and expansion in the bone marrow have not been fully detected. Furthermore, patients affected by essential thrombocythemia who are carriers of the Janus kinase 2 Val617Phe mutation show a higher incidence of venous thromboembolism both before, and at the time of diagnosis, comp…
Influence of interferon-alpha on cytokine expression by the bone marrow microenvironment--impact on treatment of myeloproliferative disorders.
1996
Myeloproliferative disorders (MPD) are characterized by several common clinical and biological features, although at the molecular level, each disease entity exhibits distinct abnormalities. IFN-alpha exerts beneficial therapeutic effects in chronic myelogenous leukemia, polycythemia vera and essential thrombocythemia, resulting in control of hematopoietic hyperplasia and, in a minority of patients, in induction of cytogenetic remission. The mechanism of action of IFN-alpha in MPD is poorly defined. Recently published in vitro findings suggest that IFN-alpha interacts with the regulation of hematopoiesis by multiple ways. Its antiproliferative activity is well known for more than a decade, …
Bone marrow fibrosis and diagnosis of essential thrombocythemia
2009
However, there are serious issues to beraisedconcerningtheauthors’analysisoftheclinicaldata,thecriteriausedtodiagnoseET,andthequantificationoffibrosis.Altogethertheauthors compared a heterogenous patient database, which included311 patients evaluated for presenting features, 299 for response totherapy,361forcomplicationrates,97forprogressionoffibrosis,andfour for reversal of BM fibrosis, so no single cohort with consistentfeatures was described throughout the study of 361 patients. Forexample, for the analysis of progression of fibrosis, only 97 (12%) oftheoriginal809patientsenteredintheUK-PT1trial
Leukocytosis is associated with poor survival but not with increased risk of thrombosis in essential thrombocythemia: a population-based study of 311…
2010
Leukocytosis is associated with poor survival but not with increased risk of thrombosis in essential thrombocythemia: a population-based study of 311 patients