Abstract
Objectives To describe a case of long-standing cryptogenic medication-resistant focal epilepsy diagnosed as FLAIR-hyperintense lesions in anti-MOG associated encephalitis with seizures (FLAMES).
Methods/Background The first cases of MOG antibody disease manifesting as unilateral encephalitis with seizures were described in 2017 (Ogawa et al., 2017). Subsequently, additional cases were used to define a clinical-radiographic syndrome of FLAMES (Budhram et al., 2019).
Results A 40-year-old female presented with sleep-related focal epilepsy in 2010. She started having focal aware seizures in wakefulness with the semiology lateralising to the right hemisphere. After good control, seizures became medication resistant, and a new focal seizure semiology emerged. In 2018 a right occipital cortex lesion was noted on MRI consistent with the new seizure semiology. A CSF examination identified intrathecal oligoclonal bands. Empirical immunotherapy had a modest effect. Worsening seizure frequency in 2021 led to inpatient evaluation. Over 200 right occipital onset focal aware seizures were recorded. A repeat MRI of the Brain identified multiple new regions of cortical FLAIR hyperintensity in the right hemisphere that corresponded to regions of increased glucose metabolism on FDG PET imaging. A brain biopsy showed an inflammatory process with lymphocytes densely aggregated around leptomeningeal vessels. CSF testing was positive for MOG IgG.
Conclusion While most FLAMES cases reported are subacute presentations, this case demonstrates FLAMES may also present as medication-resistant cryptogenic focal epilepsy with a chronic progressive course.
