Heparin-induced Thrombocytopenia As A Cause of Deep Venous Thrombosis: Effectiveness of Fondaparinux in Dialysis Patients

A 63-year-old woman with Stage 5 chronic kidney disease presented with severe weakness, nausea, and vomiting. A catheter was inserted to the right femoral vein for hemodialysis. She received low molecular weight heparin (LMWH) (enoxaparine sodyum) during two consecutive hemodialysis sessions. The patient developed swelling of the right leg four days after catheter insertion. Heparinisation with unfractionated heparin was initiated because it was thought the patient had a femoral venous catheterinduced acute deep venous thrombosis. The platelet count decreased to 23 x103 /mm3 on the first day of heparin infusion. Re-evaluation of the platelet count records showed that the number of platelets had dropped from 119 x103 /mm3 to 80 x103 /mm3 after LMWH, but this had gone unnoticed. Heparin was stopped and the patient was given Fondaparinux, a synthetic selective inhibitor of activated factor X, for alternative anticoagulation at a dose of 2.5 mg every other day subcutaenously and later started on peritoneal dialysis. The patient was discharged on warfarin after 20 days. Venous doppler revealed no thrombosis at the right main deep and surface femoral vein on the 32nd day. It seems that the deep venous thrombosis was related to Type II heparin-induced thrombocytopenia with localized vascular injury due to the hemodialysis catheter predisposing to the thrombotic event. In conclusion, heparininduced thrombocytopenia (HIT) can cause deep venous thrombosis, and should not be overlooked in patients with a reduced platelet count on dialysis. Use of Fondaparinux was effective in clearing the thrombosis.