Acquired factor V inhibitor after liver transplantation.

Acquired inhibitors against coagulation factor V (FV) occur rarely, the clinical symptoms vary to a great extent, from asymptomatic laboratory abnormalities to life-threatening bleeding. Coagulation factor V (FV) is a plasma-cofactor mostly existing in the plasma, and approximately 20-25% (Tracy et al. (1982), Kane (2006)) of FV exist in platelet granules. Patients' reaction is the prolonging of prothrombin time (PT) and activated partial thromboplastin time (APTT), but there is no exact reason, and that can not be corrected after normal plasma transfusion (Morris and Curris (2009), Lucia and Aguilar (2005)). We report here a case of the occurrence of FV inhibitors after orthotopic liver transplantation (OLT). With gastrointestinal bleeding, patient's haemostatic response was not achieved after using fresh frozenplasma (FFP), platelet concentrates (PC), prothrombin complex concentrates (PCC) or recombinant activated FVII (rFVIIa). After using high-dose intravenous immunoglobulin (IVIg) and change of immunosuppressant from tacrolimus (FK506) to cyclosporine, the bleeding stopped and better laboratory examination results was achieved thereafter.