Objective: We wished to determine the role of various factors causing hypercoagulability in thalassemia patients.
Methods: Forty-six homozygous β-thalassemia patients were investigated. Protein C, protein S, and antithrombin (AT) levels were measured and lupus anticoagulants (LA) were screened. D-Dimer and fibrinopeptide A ( FPA) levels were measured to show the activation of the fibrinolytic system. Ten healthy children served as controls.
Results: There was a marked decrease in protein C activity in 44.4% and in protein C antigen in 53.8% of the patients. Although no significant differences was noted between the mean values for protein S in the patient and control groups, protein S activity was <60% in 40% of the patients. AT levels were always normal. D-Dimer and FPA levels were increased, indicating the ongoing coagulation activation and fibrinolysis. Three patients had LA; which reflect the expression of phosphatidylserine on the outer surface of the erythrocyte membrane.
Conclusions: In thalassemic patients, there is activation of the coagulation and fibrinolytic system which is believed to be secondary to an underlying mechanism. The presence of LA in some patients, probably due to the expression of PS on the outer surface of the erythrocyte membrane, may be the initiating event. Key Words: Thalassemia-Hypercoagulability-Protein C—Protein S—Antithrombin—Antiphospholipid antibodies.
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