Co-existence of heparin-induced thrombocytopenia and thrombotic thrombocytopenic purpura in a postoperative cardiac surgery patient

Up to 50% of patients undergoing coronary artery bypass surgery will develop antibodies against the heparin-platelet factor 4 complex, and a small percentage of those will go on to develop heparin-induced thrombocytopenia. Thrombotic thrombocytopenic purpura has also been reported post-coronary artery bypass surgery. In this case report, we describe a patient who developed both heparin-induced thrombocytopenia and thrombotic thrombocytopenic purpura post-coronary artery bypass surgery. This patient had clinical features consistent with both entities, and the clinical picture could not be explained by either heparin-induced thrombocytopenia or thrombotic thrombocytopenic purpura alone. It is hypothesized that these two entities may be related in this patient population, and this case report emphasizes the challenges in the diagnosis of thrombocytopenia in this patient population.