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Semin Thromb Hemost 2006; 32(3): 231-245
DOI: 10.1055/s-2006-939434
Copyright © 2006 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA.

Analysis of Risk Factors: The Rationale of the Guidelines of the Czech Hematological Society for Diagnosis and Treatment of Chronic Myeloproliferative Disorders with Thrombocythemia

Jiří Schwarz1 , Robert Pytlík2 , Michael Doubek3 , Yvona Brychtová3 , Petr Dulíček4 , Vít Campr1 , 5 , Leoš Křen6 , Miroslav Penka7
  • 1Clinical Section, Institute of Hematology and Blood Transfusion, Prague, Czech Republic
  • 21st Department of Internal Medicine, 1st Medical Faculty, Charles University, Prague, Czech Republic
  • 3Internal Hematooncological Department, Faculty Hospital Brno-Bohunice, Masaryk University, Brno, Czech Republic
  • 41st Department of Internal Medicine, Faculty Hospital Hradec Králové, Charles University, Hradec Králové, Prague, Czech Republic
  • 5Institute of Pathological Anatomy, 2nd Medical Faculty, Charles University, Faculty Hospital Motol, Prague, Czech Republic
  • 6Department of Pathology, Faculty Hospital Brno-Bohunice, Masaryk University, Brno, Czech Republic;
  • 7Department of Clinical Hematology, Faculty Hospital Brno-Bohunice, Masaryk University, Brno, Czech Republic
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Publication History

Publication Date:
02 May 2006 (online)

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ABSTRACT

The rationale of the Czech Hematological Society guidelines for diagnosis and treatment of Philadelphia chromosome-negative myeloproliferative disorders with thrombocythemia (MPD-T) is reviewed. For diagnosis of MPD-T, the classification according to the World Health Organization or to the Rotterdam criteria is preferred because they distinguish true essential thrombocythemia from prefibrotic or early fibrotic idiopathic myelofibrosis and prepolycythemic polycythemia vera. The histopathology-based nosological distinction provided by these classifications yields valuable information on prognosis (including the risks of transition into secondary acute myeloid leukemia and myelofibrosis). Another serious complication in MPD-T is thrombosis (arterial or venous), the main risk factors of which are age, previous thrombosis, platelet counts 350 to 2200 × 109/L (peak at ~900 × 109/L) and the presence of additional thrombophilic risk factors (hereditary thrombophilia, any hypercoagulable state, cardiovascular disease). The hemorrhagic risk starts increasing progressively at platelet counts > 1000 × 109/L. Treatment should be stratified with respect to the thrombotic and hemorrhagic risks. In high-risk patients, thromboreductive therapy is warranted. All of the cytostatic drugs, including hydroxyurea, may be leukemogenic and should be given only to patients > 60 years old, whereas anagrelide or interferon α are preferred in younger individuals. In low-risk patients, antiaggregation therapy is sufficient, unless the platelet count exceeds 1000 × 109/L, which is another indication for thromboreduction. Thrombopheresis is indicated in thrombocythemia > 2000 × 109/L.

KEYWORDS

Myeloproliferative disease - essential thrombocythemia - polycythemia vera - idiopathic myelofibrosis - risk factors - thrombosis - treatment algorithm

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Jiři SchwarzM.D. 

Institute of Hematology and Blood Transfusion

U Nemocnice 1, 128 20, Prague 2, Czech Republic

Email: jiri.schwarz@uhkt.cz