Measurement of hemostatic factors in EDTA plasma.
This study determined whether immunoassays of factors VII (FVII) and VIII (FVIII) and von Willebrand factor (vWF) in EDTA-anticoagulated plasma samples are comparable to bioassays and immunoassays of these factors in citrate-anticoagulated plasma. Blood from 40 healthy volunteers was collected in EDTA- and citrate-anticoagulant tubes and assayed using immunoassays (EDTA and citrate) and clotting assays (citrate). Linear regression analyses were performed and Pearson correlation coefficients recorded. The correlation coefficients (95% confidence intervals [CIs]) between levels in EDTA- and citrate-anticoagulated plasma samples were 0.893 (0.806-0.943) for FVII antigen (ag), 0.930 (0.870-0.962) for FVIIIag, 0.990 (0.981-0.995) for vWFag, and 0.949 (0.906-0.973) for vWF activity. Coefficients (CIs) were 0.811 (0.668-0.896) for FVII coagulant activity (c) in citrate and FVIIag in EDTA and 0.608 (0.366-0.774) for FVIIIc in citrate and FVIIIag in EDTA. Measurements of FVII, FVIII, and vWF antigens in EDTA-anticoagulated plasma samples give values comparable to similar measurements in citrate-anticoagulated samples. Clotting activity, especially of FVIII, is less well correlated. Although antigen assays using EDTA are not recommended for patients with coagulopathies, they may be suitable for population-based studies.
Division of Hematology/Oncology, Department of Medicine, Northwestern University, Chicago, IL 60611, USA.
David
D
Green
Brandon
B
McMahon
Nancy
N
Foiles
Lu
L
Tian
D000328:Adult; D000925:Anticoagulants / Q000494:pharmacology*; D001800:Blood Specimen Collection / Q000379:methods; D004492:Edetic Acid / Q000494:pharmacology*; D005167:Factor VII / Q000032:analysis*; D005169:Factor VIII / Q000032:analysis*; D005260:Female; D006801:Humans; D007118:Immunoassay; D008297:Male; D008875:Middle Aged; D010949:Plasma / Q000737:chemistry; D014841:von Willebrand Factor / Q000032:analysis*
D000925:Anticoagulants; D014841:von Willebrand Factor; D005167:Factor VII; D005169:Factor VIII; D004492:Edetic Acid