The Experts below are selected from a list of 282 Experts worldwide ranked by ideXlab platform
Jan Jacques Michiels - One of the best experts on this subject based on the ideXlab platform.
-
Bone Marrow Features and Natural History of BCR/ABL-Positive Thrombocythemia and Chronic Myeloid Leukemia Compared to BCR/ABLNegative Thrombocythemia in Essential Thrombocythemia and Polycythemia Vera
Journal of Hematology and Thromboembolic Diseases, 2015Co-Authors: Jan Jacques Michiels, Fibo Ten Kate, Hendrik De Raeve, Alain GadisseurAbstract:The Hannover bone marrow (BM) classification distinguished three phenotypes of BCR/ABL-positive CML: CML of common type (CML.CT), CML with megakaryocyte increase (CML.MI) and CML with megakaryocyte predominance (CML.MP). BCR/ABL-positive essential Thrombocythemia (Ph-positive ET) is featured by CML.MP bone marrow picture of small monolobulated megakaryocytes and is part of the CML spectrum as a malignant disease (neoplasia) with an obligate transition into acute leukemia of near to 100% after 10 years follow-up. The Hannover BM classification distinguished three primary prefibrotic BCR/ABL-negative (Ph-negative) myeloproiferative disorders (MPD)s: essential Thrombocythemia (ET), polycythemia vera (PV) and chronic or primary megakaryocytic granulocytic myeloproliferation (CMGM/PMGM). The incidence of blasts crisis is low in the Phnegative MPDs ET, PV and CMGM. The risk of myelofibrosis is high in CMGM/PMGM, moderate in PV but low in Ph-negative ET. In BCR/ABL-positive Thrombocythemia the platelets are small and indolent (non-reactive) and megakaryocytes are smaller than normal with hypolobulated nuclei caused by BCR/ABL induced maturation defect. BCR/ABL-positive Thrombocythemia does not present erythromelalgic thrombotic or bleedings manifestations at increased platelet count in excess of 400 to 1500 × 109/L. The platelets and megakaryocytes in BCR/ABL-negative ET and PV are large due to growth advantage caused by constitutively activated by the JAK2V617F or MPL515 mutation. JAK2 and MPL mutated Thrombocythemias are associated with a high risk on aspirin responsive plateletmediated inflammation and thrombosis in the end-arterial circulation (platelet thrombophilia).
-
Philadelphia (Ph) chromosome-positive Thrombocythemia without features of chronic myeloid leukemia in peripheral blood: natural history and diagnostic differentiation from Ph-negative essential Thrombocythemia
Annals of Hematology, 2004Co-Authors: Jan Jacques Michiels, Wilfried Schroyens, Zwi Berneman, Jack Kutti, Birgitta Swolin, Börje Ridell, Pagani Fernando, Ulises ZanettoAbstract:We have evaluated the clinical symptoms, hematological features, and natural history of 3 cases and 20 reported cases described as Philadelphia chromosome-positive (Ph^+) essential Thrombocythemia (ET). The presence of increased small mononuclear megakaryocytes in bone marrow smears and biopsy material in patients with pronounced thrombocytosis and no evidence of chronic myeloid leukemia (CML) in peripheral blood appeared to be a diagnostic clue to the diagnosis of Ph^+ (essential) Thrombocythemia. As compared to cases of reactive thrombocytosis, the megakaryocytes in Ph^+ Thrombocythemia are smaller than normal ones and typically have hypolobulated round nuclei. This contrasts with the finding of clustered mature and enlarged megakaryocytes in Ph-negative true ET. Patients diagnosed as Ph^+ ET may progress to CML and show a high tendency to myelofibrosis and blastic transformation. These observations indicate that both Ph^+ ET and Ph^+ Thrombocythemia associated with CML can be regarded as early manifestations of the chronic stable phase of CML.
-
bilateral adrenal swelling as a cause of chest back and upper abdominal pain in essential Thrombocythemia and polycythemia vera is due to microvascular ischemic thrombosis rather than to hemorrhage
Annals of Hematology, 2002Co-Authors: Jan Jacques Michiels, Zwi N. Berneman, Wilfried Schroyens, Gabriel P KrestinAbstract:Bilateral massive adrenal swelling (BAS) on computed tomography (CT) scan with no enhancement after injection of intravenous contrast media has been observed in two completely different clinical settings. On the one hand, BAS is the result of ischemic necrosis and subsequent hemorrhagic infarction in patients with sepsis and hypotension in critically ill situations. On the other hand, BAS is the result of microvascular thrombosis, ischemia, and secondary inflammatory swelling in the setting of thrombotic conditions such as antiphospholipid syndrome (APS), heparin-induced thrombocytopenia and thrombosis (HITT), and Thrombocythemia. In this study we present evidence that the etiology of unilateral or BAS in reported cases of essential Thrombocythemia (ET) and polycythemia vera (PV) is similar to the etiology of microvascular circulation disturbances in Thrombocythemia caused by platelet-mediated inflammation and thrombosis in the peripheral, cerebral, and/or coronary endarterial microvascular circulation.
-
clinicopathological diagnosis and differential criteria of Thrombocythemias in various myeloproliferative disorders by histopathology histochemistry and immunostaining from bone marrow biopsies
Leukemia & Lymphoma, 1999Co-Authors: Juergen Thiele, Hans Michael Kvasnicka, Volker Diehl, Robert L Fischer, Jan Jacques MichielsAbstract:Differentiation of essential Thrombocythemia (ET) from Thrombocythemias occurring in various subtypes of chronic myeloproliferative disorders (MPDs) is controversial, because of the lack of uniform clinical and morphological criteria. A retrospective clinicopathologic study was performed on 375 patients presenting with a MPD and a platelet count exceeding 500 × 109/1. For comparison 35 patients with reactive thrombocytosis (RT) and five patients with a myelodysplastic syndrome (MDS-5q-syndrome) were enrolled into this study. In addition to a complete clinicopathological work-up, procedures included histochemical and immunological staining techniques and morphometry of bone marrow biopsies for proper evaluation of megakaryocytes (CD61) and erythroid precursors (Ret40f). Because of the high patient's age on admission, relative survival rates with corresponding disease-specific loss of life expectancy were calculated. Analysis of clinical and morphological characteristics, in particular megakaryopoiesis reve...
-
Erythromelalgic, Thrombotic and Hemorrhagic Manifestations in 50 Cases of Thrombocythemia
Leukemia & Lymphoma, 1996Co-Authors: Jan Jacques Michiels, Jan Lindemans, P J Van Genderen, H H Van VlietAbstract:Fifty consecutive patients with Thrombocythemia (35 men and 15 women) were diagnosed as primary Thrombocythemia (PT) in 30 and Thrombocythemia associated with polycythemia vera (PV) in 20. The symptoms were platelet-mediated erythromelalgia in 16 PT and 15 PV, coronary artery disease in 3 PT and 2 PV, atypical cerebral ischemic attacks in 8 PT and 3 PV, paradoxical thrombosis and bleeding in 3 PT and 2 PV and hemorrhages alone in 6 PT and 2 PV patients. Erythromelalgia was localized in the forefoot sole and toes in 28, the fingertips in 9, the handpalm in 2. Untreated erythromelalgia progressed to acrocyanosis or peripheral ischemia with necrosis in a toe or fingertip in 14 cases. Painful red, warm and indurated erythromelalgic hot spots in the skin of the upper legs were misdiagnosed as superficial thrombophlebitis in 5 PT and 2 PV patients.Erythromelalgia in Thrombocythemia already occurred at slightly increased platelet counts above 400 × 109/1. The curative effect of aspirin on erythromelalgia in thro...
Hiroyuki Iijima - One of the best experts on this subject based on the ideXlab platform.
-
Multiple retinal vein occlusions in essential Thrombocythemia
American journal of ophthalmology, 2002Co-Authors: Mitsuhiro Imasawa, Hiroyuki IijimaAbstract:Abstract PURPOSE: To report the ophthalmoscopic and angiographic evidence of both temporally and spatially independent multiple occlusions of the retinal veins in a patient with essential Thrombocythemia. METHODS: Observational case report. Ophthalmic examinations, including fluorescein fundus angiogram, were performed on a 77-year-old male, who was found to have essential Thrombocythemia. RESULTS: An acute impending central retinal vein occlusion in the left eye was diagnosed with coexisting old retinal vein occlusions evidenced by white vessels and capillary nonperfusion in both eyes. Peripheral retinal capillary dropout was also found angiographically in the right eye. CONCLUSION: Bilateral multiple occlusions of retinal veins in the present case suggest a prothrombotic tendency in retinal circulation in essential Thrombocythemia.
Ertugrul Ercan - One of the best experts on this subject based on the ideXlab platform.
-
Non ST-segment elevation myocardial infarction in patient with essential Thrombocythemia
Thrombosis Journal, 2009Co-Authors: Emin Alioglu, Nurullah Tuzun, Fahri Sahin, Buket Kosova, Serkan Saygi, Istemihan Tengiz, Ugur Turk, Nazan Ozsan, Ertugrul ErcanAbstract:A 68-year-old woman presented with acute chest pain and a greatly increased platelet count. Cardiac catheterization revealed subtotal occlusion and a thrombus-like filling defect in the right coronary artery. The patient was successfully treated with intravenous tirofiban. Essential Thrombocythemia was diagnosed based on bone marrow findings, clinical presentation and laboratory analysis. The relationship between intracoronary thrombus and essential Thrombocythemia is discussed.
William Townsend-pico - One of the best experts on this subject based on the ideXlab platform.
-
Essential Thrombocythemia and Central Retinal Vein Occlusion With Neovascular Glaucoma
American journal of ophthalmology, 1996Co-Authors: Marc O. Yoshizumi, William Townsend-picoAbstract:Purpose We report a case of unilateral central retinal vein occlusion resulting from essential Thrombocythemia, a rare myeloproliferative disorder with abnormally increased platelet count. Methods A 59-year-old man had central retinal vein occlusion in the left eye as the initial sign of essential Thrombocythemia. He later developed neovascular glaucoma and optic disk neovascularization. Results Laser panretinal photocoagulation, goniophotocoagulation, glaucoma medications, and control of the platelet count were effective treatment. Conclusions Early Thrombocythemia is associated with systemic and ocular thrombotic and embolic complications. Early diagnosis, recognition of ocular complications, and appropriate treatment were crucial in controlling central retinal vein occlusion and ocular neovascularization associated with essential Thrombocythemia.
Murray N. Silverstein - One of the best experts on this subject based on the ideXlab platform.
-
A clinical update in polycythemia vera and essential Thrombocythemia
The American journal of medicine, 2000Co-Authors: Ayalew Tefferi, Lawrence A. Solberg, Murray N. SilversteinAbstract:Polycythemia vera and essential Thrombocythemia pose specific management issues that distinguish them from other chronic myeloproliferative disorders. They are associated with a better prognosis, as well as a variable risk of thrombohemorrhagic complications. In addition, essential Thrombocythemia occurs comparatively more often in young people and women. Treatment strategies for patients with polycythemia vera and essential Thrombocythemia must consider the possibility of long-term survival, morbidity from thrombotic complications, transformation into myelofibrosis with myeloid metaplasia or acute myeloid leukemia, and the effect of specific therapies on the incidence of leukemic transformation and on pregnancy. There is increasing concern about the possible leukemogenic effect of hydroxyurea. Newer therapeutic agents, including interferon alpha and anagrelide, are being used more often. Ongoing studies are reexamining the effects of low-dose aspirin in preventing thrombotic complications.
-
New drugs in essential Thrombocythemia and polycythemia vera
Blood reviews, 1997Co-Authors: Ayalew Tefferi, Michelle A. Elliott, Lawrence A. Solberg, Murray N. SilversteinAbstract:Among the chronic myeloproliferative disorders, polycythemia vera and essential Thrombocythemia are unique because of their association with thrombohemorrhagic manifestations and their relatively indolent clinical course. Patients with essential Thrombocythemia may not have a significant shortening of life-expectancy and most may not require specific therapy. However, patients with polycythemia vera have a significant risk of transformation of polycythemia vera into acute leukemia or postpolycythemic myelofibrosis (or both). 'High-risk-for-thrombosis' patients with either polycythemia vera or essential Thrombocythemia require specific therapy with a platelet-lowering agent to prevent thrombotic complications. Currently, the standard agent used for this is hydroxyurea. However, its tetratogenic and leukemogenic potential has been of concern. As a result, new platelet-lowering agents are being evaluated in the treatment of polycythemia vera and essential Thrombocythemia. Anagrelide and interferon alfa are two such agents and have been shown to be effective in reducing platelet counts in patients with chronic myeloproliferative disorders. The putative mechanism of action of these drugs, their specific activity in polycythemia vera and essential Thrombocythemia, side-effect profile, and current indications are discussed herein.
-
Essential Thrombocythemia in Young Adults
Mayo Clinic proceedings, 1991Co-Authors: Kristi J. Mcintyre, Murray N. Silverstein, H. Clark Hoagland, Robert M. PetittAbstract:Essential Thrombocythemia is typically a disorder of adults in the sixth or seventh decade of life and is characterized by frequent thrombohemorrhagic complications. In young patients, the optimal management of complications is controversial. We studied 56 young adults (33 female and 23 male patients) with a diagnosis of essential Thrombocythemia. The mean duration of follow-up was 4.68 years. The mean platelet count at diagnosis was 1,328,000/mm3. Platelet aggregation studies in 21 patients demonstrated hypoaggregation to epinephrine; spontaneous platelet aggregation was present in 4. At diagnosis, 39 patients were asymptomatic, and thrombocytosis was discovered incidentally. Throughout follow-up (up to 20 years), 24 patients remained asymptomatic. Thrombotic complications developed in 24 patients; they were life-threatening in only 3. The most common vaso-occlusive symptoms were migraine headache (in 12 patients) and erythromelalgia (in 3). Minor hemorrhagic complications occurred in six patients, and none was life-threatening. Serious complications (one cerebral and two myocardial infarctions) occurred in three patients, all of whom recovered. Two deaths occurred, neither of which was attributable to essential Thrombocythemia. The treatment regimens used were chemotherapy in 9 patients, antiaggregating agents in 7, radioactive phosphorus in 1, the newer platelet-lowering agent anagrelide in 10, and only observation in 29. No treatment-related acute leukemias developed. This series of young patients with essential Thrombocythemia, the largest to date, demonstrates a low incidence of life-threatening complications and a favorable long-term prognosis. Therapeutic recommendations should remain conservative, and potential leukemogens should be avoided unless serious complications develop. Anagrelide may be useful in young patients with Thrombocythemia who are symptomatic.
