Heparin-induced thrombocytopenia in hemodialysis patients.

This study was conducted to determine the incidence of heparin-induced thrombocytopenia (HIT), an important complication in heparin therapy, in 154 hemodialysis patients, with characterization of the subtypes using an enzyme-linked immunosorbent assay. The etiology of the immunologic type of HIT is suggested to involve the binding of a specific antibody for platelet factor 4-heparin complex to platelets and their consequent activation. The 154 consecutive patients were newly treated with hemodialysis due to chronic or acute renal failure between January 1993 and July 1995. Heparin-induced thrombocytopenia was suspected in six patients (3.9%), and its presence was confirmed by platelet aggregation testing. Five of the patients with HIT had anti-platelet factor 4-heparin complex antibody detected by the enzyme-linked immunosorbent assay and were diagnosed with immunologic HIT. The patient who did not have the antibody was thought to have another type of HIT.