Two global haemostatic assays as additional tools to monitor treatment in cases of haemophilia A

Abstract

Haemophilia A patients with similar levels of factor VIII (FVIII) may have different bleeding phenotypes and responses to treatment with FVIII concentrate. Therefore, a test which determines overall haemostasis may be appropriate for treatment monitoring in some patients. We studied two global haemostatic methods:endogenous thrombin potential (ETP) and overall haemostatic potential(OHP) before and after injection of FVIII concentrate in patients with haemophilia A treated prophylactically and on-demand. A significant correlation between FVIII and both ETP and OHP was observed, while ETP and OHP differed between patients with severe and mild clinical phenotypes. Both ETP and OHP differed significantly between severe, moderate and mild haemophilia A and controls. ETP and OHP increased after intravenous injection of FVIII concentrate in both groups of patients, but in spite of higher pre-treatment values of both ETP and OHP in patients treated prophylactically, and much higher post-treatment FVIII levels in comparison with the values in patients treated on-demand, no difference after treatment was observed for either ETP or OHP. ETP and OHP may be additional alternatives for monitoring (and even for individual tailoring) treatment in patients with haemophilia A.

Is a decrease of microparticles related to improvement of hemostasis after FVIII injection in hemophilia A patients treated on demand?

“…Eighteen patients treated on demand at the Hemostasis Department and Hemophilia Centre, Belgrade, Serbia, were part of a larger study that included patients treated both on demand and prophylactically [12,13]. On-demand treatment is the replacement of coagulation factors following a bleeding or bleeding-like symptoms.…”

“…Absorbance (Abs) at 405 nm is measured each minute for 40 min to construct the fibrin-aggregation curve. The area under the curve is expressed by a summation of the Abs values (Abs-sum) [12]. The latter results have been used in a larger study previously published [12,13].…”

“…The area under the curve is expressed by a summation of the Abs values (Abs-sum) [12]. The latter results have been used in a larger study previously published [12,13]. Comparison was also made with fibrin gel structure (unpublished data, manuscript in preparation), which was determined according to previously published procedures [17].…”

Does the intensity and quality of treatment and not only the factor VIII level influence global hemostasis in patients with hemophilia A?

“…Although it is generally accepted that a clinical status depends primarily on FVIII level, it has been shown that measurement of TG can reflect the clinical bleeding phenotype better than the FVIII level [2][3]. Overall Hemostatic Potential (OHP), a method assessing both coagulation and the fibrinolysis may also be a promising tool for the evaluation of hemostatic capacity in hA [3].…”

“…Overall Hemostatic Potential (OHP), a method assessing both coagulation and the fibrinolysis may also be a promising tool for the evaluation of hemostatic capacity in hA [3].…”