Ischemic stroke in pediatric moyamoya disease associated with immune thrombocytopenia—a case report

Case report: A 10-year-old boy developed refractory bleeding and was diagnosed with immune thrombocytopenia (ITP). He was treated with steroids and intravenous immunoglobulin (IVIG). Five months later, however, he developed right homonymous hemianopsia, sensory aphasia, agraphia, and agnosia. MR imaging demonstrated multiple cerebral infarction in the bilateral cerebral hemispheres, and MR angiography revealed severe stenosis of the bilateral internal carotid arteries. He was diagnosed with moyamoya disease and successfully underwent surgical revascularization on both sides under IVIG therapy. However, multiple cerebral infarcts developed in the bilateral cerebral hemispheres 10 days after the second surgical revascularization when platelet counts were within normal limits. Furthermore, chronic subdural hematoma gradually increased in size after each surgery, which required burr hole surgery to resolve increased intracranial pressure, when platelet counts decreased to less than 10 × 10⁹/L. Conclusion: This is the first report presenting a case with moyamoya disease coincident with ITP. Critical managements would be essential to reduce perioperative complications, because ITP is known to provoke both hemorrhagic and ischemic events through multiple mechanisms.