Fibrinolytic imbalance in essential thrombocythemia: role of platelets.
Thrombotic and hemorrhagic complications are frequent in patients with essential thrombocythemia (ET), a myeloproliferative syndrome with an increased number of circulating platelets. Since platelets are a physiological reservoir for the plasminogen activator inhibitor (PAI-1) contained in plasma, we evaluated plasma and platelet tissue plasminogen activator (tPA) and PAI-1 in 20 ET patients with and without thrombotic complications and in 13 control subjects. In ET patients with thrombotic complications there was a significantly greater platelet PAI-1 functional activity than in ET patients without thrombotic complications and in the control group (p < 0.05 and p < 0.025, respectively). Moreover, platelet tPA activity was significantly low in all ET patients (p < 0.001). This fibrinolytic imbalance (increased plasminogen inhibitor and lowered activator) might be a critical cofactor in the thrombotic complications in ET patients.
Bazzan
M
M
Department of Medicine and Experimental Oncology, Division of Hematology, Turin, Italy.
Tamponi
G
G
Gallo
E
E
Stella
S
S
Schinco
P C
PC
Pannocchia
A
A
Pileri
A
A
D000328:Adult; D000368:Aged; D001792:Blood Platelets / Q000737:chemistry*; D004198:Disease Susceptibility; D005260:Female; D005342:Fibrinolysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D017395:Plasminogen Activator Inhibitor 1 / Q000097:blood*; D010976:Platelet Count; D013920:Thrombocythemia, Essential / Q000097:blood* / Q000150:complications; D013927:Thrombosis / Q000209:etiology; D010959:Tissue Plasminogen Activator / Q000097:blood*
D017395:Plasminogen Activator Inhibitor 1; D010959:Tissue Plasminogen Activator