Cerebral venous sinus thrombosis in immune thrombocytopenia patients treated with thrombopoietin receptor agonist: Case reports and literature review.

Introduction and importance: Cerebral venous sinus thrombosis is an uncommon adverse event in immune thrombocytopenia (ITP) patients treated with thrombopoietin receptor agonists (TPO-RAs). Case presentation: We reported two cases of cerebral venous sinus thrombosis after eltrombopag administration. The first case is a 29-year-old ITP woman who recently initiated eltrombopag one month before admission. She presented with progressive headache, visual disturbance, and nausea for six days with unremarkable physical examination except for bilateral optic disc edema. She was treated with enoxaparin and switched to edoxaban when discharged. The second case is a 75-year-old man with a history of vaccine-induced ITP. He was initially treated with dexamethasone and eltrombopag. One month later, he developed acute cerebral venous thrombosis with hemorrhagic infarction in the bilateral frontal lobes. Even though he was treated with intravenous heparin, his status was not improved. He received the best supportive care. Discussion: The pathophysiology of TPO-RAs-associated cerebral venous sinus thrombosis remained unclear but might associate with platelet activation. Most cases of cerebral venous sinus thrombosis occur within two months, thus closed platelet monitoring is important. Conclusion: Careful use and closed monitoring might prevent this event. Indications of initiation and tapering must be considered before TPO-RAs administration. Off-label use may enhance TPO-RA side effects.