Normal hemostatic parameters in children and young adults with α-thalassemia diseases.

Thalassemia intermedia (TI), a non-transfusion dependent thalassemia, is divided into α-thalassemia, such as HbH disease, and β-thalassemia diseases, such as HbE/β thromboembolism (TE) in TI has been mostly reported in β-thalassemia diseases with incidence rates of 3.9-29%. The present study enrolled 60 patients with α-thalassemia intermedia. The control groups were thalassemia major (TM) consisting of 17 patients diagnosed with β-thalassemia diseases, 24 patients diagnosed with splenectomized β-thalassemia diseases and 25 normal subjects. The mean±SD ages were 12.9±5.3, 15.0±3.8, 15.7±4.1 and 12.3±2.5years respectively. The coagulation markers in α-thalassemia patients, including D-dimer, thrombin-antithrombin complex (TAT) and prothrombin fragment (F1.2), were not significantly different compared to the levels in normal subjects. Similar results were found for the thromboelastometry, which is a method to assess global hemostasis involving the functions of coagulation and anticoagulation proteins, fibrinolysis and platelets. The hypercoagulability could be demonstrated in TM by high TAT in severe β-thalassemia patients and high TAT and D-dimer, shortened CT and CFT, high alpha angle, A20 and MCF only in the splenectomized β-thalassemia patients.