Summary

We reported a rare case of Budd-Chiari syndrome (BCS) associated with tamoxifen use, which was later complicated by heparin-induced thrombocytopenia and thrombosis (HITT). The patient was a 44 year-old woman with a medical history of lobular carcinoma in situ, who had been on tamoxifen for 2 years, presented with abdominal pain and distention. Imaging studies followed by a liver biopsy confirmed the diagnosis of BCS. On extensive work-up, the patient was found to have an unclassified myeloproliferative disorder with positive JAK-2 V617 mutation. After discontinuing tamoxifen, the patient was started on intravenous heparin. However, later in the course, she developed HITT. Myeloproliferative disorder, in conjunction with tamoxifen, predisposed the patient to be highly thrombophilic resulting in BCS. HITT was found to be relatively common in BCS. Anticoagulation and blood count need to be carefully monitored, and the possibility of HITT emergence in these patients should always be kept in mind.