Procoagulant Imbalance in Klinefelter Syndrome Assessed by Thrombin Generation Assay and Whole-Blood Thromboelastometry

Abstract Context Klinefelter syndrome (KS) is a condition at increased risk of thrombosis compared to 46,XY men. Objective This work aimed to investigate the coagulation balance of KS patients by thrombin generation assay (TGA) and thromboelastometry. Methods An observational, cross-sectional study was conducted at 3 tertiary endocrinological centers in Milan, Italy. Fifty-eight KS patients and 58 age-matched healthy controls were included. Anticoagulant or antiplatelet therapy and known coagulation disorders were exclusion criteria. TGA was performed in platelet-poor plasma (PPP) and platelet-rich plasma (PRP). Whole-blood thromboelastometry and activities of coagulation factors were assessed. Endogenous thrombin potential (ETP), the area under the thrombin generation curve, assessed with and without thrombomodulin (ETP-TM+ and ETP-TM–), and their ratio (ETP ratio), were considered as indexes of procoagulant imbalance. Results Patients with KS displayed higher PPP-ETP-TM+ (mean 1528 vs 0.1315 nM × min; P