A 5-year-old male presented with three days of fevers, headaches, and vomiting with new onset seizures. MRI showed left hemispheric leptomeningeal enhancement without diffusion restriction. Cerebrospinal fluid (CSF) analysis was unremarkable and infectious testing was negative. He subsequently developed nonconvulsive focal status epilepticus. Repeat MRI showed FLAIR hyperintense lesions with diffusion restriction involving the left hemispheric cortex. Serum MOG-IgG titers were elevated. He was treated with high-dose steroids and improved. 

Similarly, a 2-year-old male presented with four days of fevers, headaches, and vomiting with new onset seizures. He also developed nonconvulsive focal status epilepticus. His seizures were refractory to midazolam infusion and required pentobarbital. CSF analysis showed an elevated white blood cell count with a lymphocytic predominance and negative infectious testing. MRI showed bilateral cortical FLAIR hyperintensities with diffusion restriction. He was treated with high-dose steroids given concerns for an inflammatory etiology. Serum MOG-IgG titers were elevated, after which he was treated with another course of steroids and intravenous immune globulin (IVIg) with improvement.