Olanzapine-Associated Portal and Superior Mesenteric Vein Thrombosis

摘要

To the Editor: An increasing number of reports suggest a link between venous thromboembolism (VTE) and the use of antipsychotics. We report the case of an obese 57-year-old woman, with a diagnosis of schizophrenia in chronic treatment with olanzapine 10 mg/d, admitted to the emergency department with acute abdominal pain, vomiting, and drowsiness. A total-body computed tomography showed splanchnic thrombosis (SVT), manifested as portal vein thrombosis and superior mesenteric vein thrombosis associated with intestinal ischemia and segmental pulmonary embolism (PE). The patient was transferred to the intensive care unit, where she was intubated and subjected to mechanical ventilation; then, an urgent laparotomy was performed, with a resection of the small bowel (50 cm) and an ileojejunal anastomosis. Anticoagulation treatment was started the same day of surgery with high dose of enoxaparin (180 mg daily). Unfortunately, she developed acute renal failure and systemic infections, for which weaning from ventilation has been possible only after 22 days. A hypercoagulability panel, which included the presence of factor V Leiden, the G20210A prothrombin gene mutation, homocysteine level, antiphospholipid antibodies and level of protein C and protein S, was negative. The suspicion that olanzapine could be involved in the development of the thrombotic events came out because the Naranjo score resulted to be 6. In other words, the relationship between the thrombotic disease and the assumption of olanzapine was probable. Finally, she was discharged from the hospital treated with an anti-vitamin K drug (acenocoumarol) and olanzapine. The use of direct oral anticoagulants is not allowed yet for patients with splanchnic vein thrombosis. A follow-up was planned at our Thrombosis Center along with a regularly clinical control by her psychiatrist.