title: Evaluation of the use of global haemostasis assays to monitor treatment in factor XI deficiency.
abstract: BACKGROUND
  Previous guidelines recommend that FXI:C levels should be used to monitor FXI replacement in factor XI (FXI) deficiency. However, FXI:C levels do not correlate with bleeding tendency in this disorder and may not be the optimal test by which to monitor and determine further treatment in the postoperative period.
  
  
  OBJECTIVE
  To assess whether the thrombin generation assay (TGA) and rotational thromboelastometry can be used to monitor FXI replacement peri-operatively in FXI deficiency and to determine if changes in FXI:C levels correlate with changes in thrombin generation and clot formation parameters following treatment with solvent-detergent fresh frozen plasma (SD-FFP).
  
  
  METHODS
  The TGA and rotational thromboelastometry were used to measure thrombin generation and clot formation in 11 adults with FXI deficiency who were treated with either SD-FFP (n = 8) or FXI concentrate (n = 3) as prophylaxis peri-operatively. Blood samples were taken pre- and 30 min post-treatment.
  
  
  RESULTS
  Global haemostasis assays can be used to measure the effect of FXI replacement with SD-FFP or FXI concentrate in FXI deficiency. Both treatment types improved thrombin generation and clot formation. However, the remaining response to treatment at 24 h post SD-FFP was variable and changes in FXI:C levels were not predictive of changes in thrombin generation/thromboelastometry parameters after treatment with SD-FFP.
  
  
  CONCLUSIONS
  Global haemostasis assays may provide a more reliable means of monitoring SD-FFP treatment with the potential to prevent individuals receiving unnecessary treatment, however, their clinical use in decision making needs to be tested in a larger prospective study.
authors.affiliation: Department of Haematology, Manchester Royal Infirmary, Central Manchester University Hospital NHS Trust, Manchester, UK.|Institute of Cancer Sciences, The University of Manchester, Manchester, UK.
authors.forename: G N
authors.initials: GN
authors.lastname: Pike
authors.affiliation: Haematology Molecular Diagnostics Centre, Manchester Royal Infirmary, Central Manchester University Hospital NHS Trust, Manchester, UK.
authors.forename: A M
authors.initials: AM
authors.lastname: Cumming
authors.affiliation: Department of Haematology, Manchester Royal Infirmary, Central Manchester University Hospital NHS Trust, Manchester, UK.
authors.forename: J
authors.initials: J
authors.lastname: Thachil
authors.affiliation: Department of Haematology, Manchester Royal Infirmary, Central Manchester University Hospital NHS Trust, Manchester, UK.|The University of Manchester, Manchester, UK.
authors.forename: C R M
authors.initials: CR
authors.lastname: Hay
authors.affiliation: Department of Haematology, Manchester Royal Infirmary, Central Manchester University Hospital NHS Trust, Manchester, UK.|Institute of Cancer Sciences, The University of Manchester, Manchester, UK.
authors.forename: J
authors.initials: J
authors.lastname: Burthem
authors.affiliation: The University of Manchester, Manchester, UK.|SHOT Office, Manchester Blood Centre, Plymouth Grove, Manchester, UK.
authors.forename: P H B
authors.initials: PH
authors.lastname: Bolton-Maggs
mesh_terms: D000328:Adult; D000368:Aged; D005173:Factor XI Deficiency / Q000188:drug therapy*; D005260:Female; D006487:Hemostasis / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged
keywords: bleeding disorder; blood coagulation; factor XI; factor XI deficiency; thrombin generation; thromboelastometry