Severe thrombotic complications associated with activated protein C resistance acquired by orthotopic liver transplantation.
We report a patient who developed recurrent hepatic artery thrombosis and deep venous thrombosis following orthotopic liver transplantation. Investigations revealed the presence of activated protein C (APC) resistance due to a mutation in the factor V gene in the transplanted liver. The patient's own peripheral blood cells did not carry the mutation. Although part of factor V is located in the platelets and may be endogenously synthesized by megakaryocytes, this case demonstrates the major clinical importance of hepatic-derived factor V. It may be reasonable to screen liver donors with a history of a thrombotic event for APC, and to consider anticoagulation in the recipients of livers positive for this defect.