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Publications (2)2.95 Total impact

  • Article: Relationship between ABO blood groups and von Willebrand factor, ADAMTS13 and factor VIII in patients undergoing hemodialysis.
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    ABSTRACT: Several studies have demonstrated that non-O blood groups subjects present an increased VTE risk as compared to those carrying O blood group. The aim of this study was to investigate the ABO blood groups influence on factor VIII (FVIII) activity, von Willebrand factor (VWF), and ADAMTS13 plasma levels in patients undergoing hemodialysis (HD). Patients undergoing HD (N=195) and 80 healthy subjects (control group) were eligible for this cross-sectional study. The ABO blood group phenotyping was performed by the reverse technique. FVIII activity was measured through coagulometric method, and VWF and ADAMTS13 antigens were assessed by ELISA. FVIII activity and VWF levels were significantly higher and ADAMTS13 levels was decreased in HD patients, as compared to healthy subjects (P < 0.001, in three cases). HD patients carrying non-O blood groups showed a significant increase in FVIII activity (P = 0.001) and VWF levels (P < 0.001) when compared to carriers of O blood group. However, no significant difference was observed in ADAMTS13 levels (P = 0.767). In the control group, increased in FVIII activity (P = 0.001) and VWF levels (P = 0.002) and decreased in ADAMTS13 levels (P = 0.005) were observed in subjects carrying non-O blood groups as compared to carriers of O blood group.Our data confirmed that ABO blood group is an important risk factor for increased procoagulant factors in plasma, as FVIII and VWF. Admitting the possible role of kidneys in ADAMTS13 synthesis or on its metabolism, HD patients were not able to increase ADAMTS13 levels in order to compensate the increase of VWF levels mediated by ABO blood groups. Considering that non-O blood groups constitute a risk factor for thrombosis, it is reasonable to admit that A, B and AB HD patients need a careful and continuous follow-up in order to minimize thrombotic events.
    Journal of Thrombosis and Thrombolysis 04/2012; 33(4):416-21. · 1.48 Impact Factor
  • Article: ADAMTS13 and Von Willebrand factor in patients undergoing hemodialysis.
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    ABSTRACT: Hemodialysis (HD) is associated with increasing thrombotic trend. Vascular access thrombosis (VAT) increases morbidity in HD patients. The aim of this study was to evaluate ADAMTS13 and VWF plasma levels from patients undergoing HD as putative biomarkers of the hypercoagulability state, as well the association between these markers and VAT occurrence. This study included 195 patients on HD for more than 6 months. HD patients were allocated into two groups according to the occurrence or not of previous episode of VAT; HD with VAT (N = 46) and HD without VAT (N = 149). ADAMTS13 and VWF were performed by ELISA. There was no significant difference between HD patients with and without VAT for ADAMTS13 and VWF levels. However, VWF levels were higher (P < 0.001) and ADAMTS13 were lower (P < 0.001) in HD patients, comparing to the control group composed by healthy subjects without kidney disease, age and sex-matched (N = 80). Taken together our data suggest a potential role of the kidneys function compromised on ADAMTS13 synthesis or metabolism, regardless other known sources of ADAMTS13. The imbalance between ADAMTS13 and VWF levels does not explain the development of VAT in HD patients by itself, although it should contribute for the hypercoagulability state. Therefore, additional studies to identify other risk factors are warranted and essential for better management of HD patients.
    Journal of Thrombosis and Thrombolysis 02/2012; 34(1):73-8. · 1.48 Impact Factor