Plasmapheresis in the management of heparin-associated thrombocytopenia with thrombosis.

Heparin-associated thrombocytopenia with thrombosis (HATT) is fatal in 29% and leads to limb amputation in another 21% of patients. Patients with arterial thrombosis do worse than do those with venous thrombosis alone. Heparin-associated thrombocytopenia is mediated through IgG or IgM immunoglobulin fractions and is believed to be an immune phenomenon, with heparin acting as a hapten. In addition, endothelial injury may be responsible for the development of thrombosis. Heparin-induced platelet aggregation persists for weeks to months after its withdrawal in these patients. Acute management of HATT includes surgical thrombectomy, thrombolytic therapy, dextran, ancrod, low-molecular-weight heparin, and antiplatelet agents, but overall results remain unsatisfactory. We report the use of plasmapheresis, along with aspirin and dextran, in a patient with HATT. The patient experienced pain relief in 1 day; the heparin-associated platelet aggregation test became negative in 5 days, and there was functional salvage of the affected limb. We suggest that plasmapheresis may be an effective therapy in the management of HATT.