Pearls & Oy-sters: Multiple ischemic strokes secondary to heparin-induced thrombocytopenia

Abstract

A 57-year-old right-handed woman developed sudden onset right-sided weakness and recurrent falls while on warfarin 13 days after being diagnosed with HIT. Three weeks prior, she had an elective hysterectomy and salpingo-oophorectomy for fibroids and menorrhagia complicated by postoperative pulmonary emboli. She had been treated with unfractionated heparin for 4 days, and then began low-molecular-weight heparin for 7 days. Her initial platelet count was within normal limits at 156 × 109 g/dL. The diagnosis of HIT was based on a platelet count of 67 × 109 g/dL with a nadir of 44 × 109 g/dL, positive platelet factor antibody-4 by ELISA, and abnormal heparin-induced platelet aggregation assay. Other causes of thrombocytopenia were ruled out. As her initial treatment for HIT, she received argatroban for 8 days and was discharged from the hospital on warfarin and fondaparinux with a platelet count of 75 × 109 g/dL. Fondaparinux was stopped 4 days later given an international normalized ratio (INR) = 3 while warfarin was continued. Her past medical history was negative for stroke but significant for tobacco use and recent onset of hypertension. On admission examination, she had cognitive …