COAGULATION PARAMETERS OF ABO GROUP-SPECIFIC CRYOSUPERNATANT

Patients with thrombotic thrombocytopenic purpura that is refractory t o conventional fresh frozen plasma (FFP) exchange therapy are sometime s switched to cryosupernatant as the replacement fluid, although its h emostatic properties are not well defined. We performed several key co agulation assays on three pools of four units from each of three ABO g roups of cryosupernatant and FFP. Fibrinogen, factor VIII activity, an d von Willebrand factor antigen (vWF:Ag) levels were all significantly lower in cryosupernatant compared with FFP, although at levels usuall y not considered clinically significant. We confirmed that group O FFP contained significantly less factor VIII activity and vWF:Ag compared with groups AB and B. In contrast to FFP, group AB cryosupernatant co ntained lower levels of fibrinogen, factor V activity, factor VIII act ivity, and vWF:Ag than groups O or B. Group AB cryosupernatant, with t he lowest levels of vWF:Ag and universal ABO compatibility, may be the product of choice for refractory thrombotic thrombocytopenic purpura.