Anticoagulation with r-hirudin in regular haemodialysis with heparin-induced thrombocytopenia (HIT II). The first long-term application of r-hirudin in a haemodialysis patient.

A 69-year-old female patient with renal failure developed heparin-induced thrombocytopenia type II (HIT II) two months after starting haemodialysis therapy with heparin as anticoagulant and a 6-week course of thromboembolism prophylaxis with enoxaparin sodium. The platelet count dropped by 50% as compared with initial values and ex vivo platelet aggregation induced by heparin antibodies (HIPA-test) was detected. Haemodialysis therapy was complicated by a massive thrombosis of dialyzer and ensuing repeated interruptions of treatment. After confirmation of the diagnosis of HIT II haemodialysis therapy was continued with hirudin as anticoagulant. Polysulfone dialyzers and an intravenous bolus of 0.14 mg/kg of recombinant hirudin (r-hirudin) achieved efficient haemodialysis therapy of 4.5 hours, with a minimum therapeutic blood level of hirudin of 0.5 micrograms/mL. More than 50 regular haemodialysis with hirudin anticoagulation were performed without additional problems. The ecarin clotting time (ECT) was used as bedside method to monitor blood levels and for dosage adjustments of hirudin. After the 34th haemodialysis, the frequency (previously 3-4 haemodialyses sessions/week) was reduced to 2 sessions/week. The creatinine clearance increased continuously from initially 2.6 to 10.4 ml/min after the 13th week of hirudin-anticoagulated haemodialysis and the platelet count normalized. In conclusion, we report the first long-term administration of r-hirudin to a patient on regular haemodialysis therapy complicated by heparin-induced thrombocytopenia. The use of hirudin as anticoagulant along with dialyzers impermeable to hirudin offers a novel alternative means of anticoagulation and, even in patients with HIT, enables performing an efficient haemodialysis therapy. Hirudin dosage must be individually adjusted by using bedside drug monitoring of plasma concentrations.