TY - JOUR
T1 - Thrombosis in myeloproliferative disorders
T2 - Prevalence, prognostic factors, and the role of leukocytes and JAK2V617F
AU - Tefferi, Ayalew
AU - Elliott, Michelle
PY - 2007/6
Y1 - 2007/6
N2 - An underlying myeloproliferative disorder (MPD), especially polycythemia vera (PV) or essential thrombocythemia (ET), is a risk factor for thrombosis. Considering large selected studies, prevalence rates for major thrombosis, at time of diagnosis, range from ∼34 to 39% for PV and 10 to 29% for ET; the corresponding figures for thrombosis at follow-up are ∼8 to 19% for PV and 8 to 31% for ET. In all instances, arterial events were more frequent than venous events. In both PV and ET, advanced age and history of thrombosis are independent predictors of recurrent thrombosis. In addition, leukocytosis, but not thrombocytosis, has been identified as a potential risk factor for thrombosis in both diseases. The particular observation is consistent with the laboratory demonstration, in these disorders, of increased number of activated granulocytes and granulocyte-platelet aggregates, upregulation of platelet P-selectin and tissue factor expression by granulocytes, and the antithrombotic value of hydroxyurea therapy. Most recently, a JAK2 gain-of-function mutation (JAK2V617F) was described in virtually all patients with PV and ∼50% of those with ET. Whether the presence of this specific mutation or its allele burden modifies the risk of thrombosis in patients with MPDs currently is under investigation.
AB - An underlying myeloproliferative disorder (MPD), especially polycythemia vera (PV) or essential thrombocythemia (ET), is a risk factor for thrombosis. Considering large selected studies, prevalence rates for major thrombosis, at time of diagnosis, range from ∼34 to 39% for PV and 10 to 29% for ET; the corresponding figures for thrombosis at follow-up are ∼8 to 19% for PV and 8 to 31% for ET. In all instances, arterial events were more frequent than venous events. In both PV and ET, advanced age and history of thrombosis are independent predictors of recurrent thrombosis. In addition, leukocytosis, but not thrombocytosis, has been identified as a potential risk factor for thrombosis in both diseases. The particular observation is consistent with the laboratory demonstration, in these disorders, of increased number of activated granulocytes and granulocyte-platelet aggregates, upregulation of platelet P-selectin and tissue factor expression by granulocytes, and the antithrombotic value of hydroxyurea therapy. Most recently, a JAK2 gain-of-function mutation (JAK2V617F) was described in virtually all patients with PV and ∼50% of those with ET. Whether the presence of this specific mutation or its allele burden modifies the risk of thrombosis in patients with MPDs currently is under investigation.
KW - JAK2
KW - Myeloproliferative
KW - Polycythemia
KW - Thrombocythemia
KW - Thrombosis
UR - http://www.scopus.com/inward/record.url?scp=34249949626&partnerID=8YFLogxK
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U2 - 10.1055/s-2007-976165
DO - 10.1055/s-2007-976165
M3 - Review article
C2 - 17525888
AN - SCOPUS:34249949626
SN - 0094-6176
VL - 33
SP - 313
EP - 320
JO - Seminars in Thrombosis and Hemostasis
JF - Seminars in Thrombosis and Hemostasis
IS - 4
ER -