Associated thrombophilic defects in essential thrombocythemia: their relationship with clinical manifestations

KORNBLIHTT LAURA I; HELLER PAULA G; CORREA GABRIEL; CASTAÑÓN MARÍA M; GENOUD VALERIA; VASSALLU PATRICIA S; SARANO JUDITH; KORDICH LUCÍA; MOLINAS FELISA C

THROMBOSIS RESEARCH

Elsevier

Año: 2003 vol. 112 p. 131 - 135

0049-3848

   In order to assess the contribution of genetic and acquired thrombophilic defects in the pathogenesis of thrombosis in essential thrombocythaemia, we evaluated the presence of factor V Leiden, prothrombin G20210A and methylenetetrahydrofolate reductase C677T polymorphisms, protein C, protein S and antithrombin III levels, activated protein C resistance, lupus anticoagulant, anticardiolipin, antiphospholipid and anti b2 glycoprotein antibodies and homocysteinemia in 60 ET patients, 17 with major vascular events and 19 with microvascular disturbances. The allele frequency of prothrombin G20210A polymorphism in ET was higher than in a normal population (5% vs 0.71%, p=0.04) while no difference was found for factor V Leiden (0.83% vs 1.43%) nor methylenetetrahydrofolate reductase C677T polymorphism (35.8% vs 34.3%,  p=0.9). Deficiency of protein C, protein S and antithrombin III levels were not found in any patient although median protein S levels were lower than in controls (89% vs 110%, p= .007). Two patients had activated protein C resistance, 6 harboured antiphospholipid antibodies and 5 had hyperhomocysteinemia. Although thrombophilic conditions were detected in one third of our patients with ET, no correlation was found between these prothrombotic factors and the development of MVE while the frequency of MV disturbances was slightly increased. Testing for thrombophilia in ET might not be helpful to identify patients at risk for thrombosis and routine screening for these conditions may not be justified.