Fondaparinux therapy in a hemodialysis patient with heparin-induced thrombocytopenia type II

Abstract

The successful use of fondaparinux in a hemodialysis patient with heparin-induced thrombocytopenia type II (HIT II) is reported. An 85-year-old, 68-kg Caucasian woman came to the emergency department with shortness of breath and exertional chest pain radiating to the neck. Testing revealed non-ST-segment elevation myocardial infarction, severe coronary artery disease, mitral regurgitation, left ventricular dysfunction, an ejection fraction of 25-30%, and pulmonary arterial hypertension. I.V. unfractionated heparin was given for therapeutic anticoagulation per hospital protocol and discontinued on hospital day 3 before mitral valve repair and coronary bypass procedure. Postoperatively unfractionated heparin and low-molecular-weight heparin were avoided because of a reduction in the platelet count and suspicion of HIT. Instead, the patient was placed on sequential compression devices in addition to aspirin for prophylaxis of deep venous thrombosis. By postoperative day 6, the patient's platelet count dropped 76% from baseline, and the patient was found to have heparin-dependent platelet factor 4 antibodies. Argatroban infusion was initiated but discontinued after 2 days due to bleeding. Fondaparinux was ordered for anticoagulation therapy. By hospital day 8, the patient developed renal insufficiency requiring hemodialysis and adjustment of the fondaparinux regimen. During the 30-day course of fondaparinux, the patient did not experience thromboembolic events or bleeding and did not require transfusions. There was no clotting within hemodialysis membranes, and her hepatic function improved by the time of her discharge. Fondaparinux was used in a hemodialysis patient with HIT II without the development of thromboembolic, hemodialysis-clotting, thrombocytopenic, or hemorrhagic complications. The patient's platelet count remained in the normal range during the 30-day course of fondaparinux.