A patient with concurrent multiple sclerosis and moyamoya disease

Background: Moyamoya disease (MMD) is a rare vasculopathy and Multiple Sclerosis (MS) is an autoimmune disease which causes CNS demyelination. While most literature has focused on misdiagnosis of MMD as an "MS mimic", we present a patient in which both co-existed.Methods: Case ReportResults: A 57-year-old woman presented with gait dysfunction and paresthesias in both feet. MRI revealed brain and spinal cord lesions consistent with MS. Vessel imaging revealed multivessel stenosis consistent with MMD. Lumbar puncture demonstrated oligoclonal bands, leading to two diagnoses, MS and MMD.Conclusions: MS can exist concurrently with MMD, potentially due to underlying propensity for autoimmunity.