Non-paraneoplastic limbic encephalitis characterized by mesio-temporal seizures and extratemporal lesions: A case report

Limbic encephalitis (LE) can be either paraneoplastic or a non-paraneoplastic autoimmune disorder. Magnetic resonance imaging (MRI) of the brain on T2-weighted fluid-attenuated inversion recovery (FLAIR) classically shows hyperintensities of the temporal structures, but multifocal involvement of extratemporal cortex has also been described in paraneoplastic LE. Here we describe a 27-year-old woman whose idiopathic autoimmune (glutamic acid decarboxylase-antibody positive) LE debuted with multiple daily mesio-temporal seizures, amnesia and multifocal extratemporal cortical MRI abnormalities. Mesio-temporal MRI signal increase was found after 20 days. This case report highlights that early diagnosis of non-paraneoplastic LE may be considered in patients with multiple daily mesio-temporal seizures and amnesia even in the absence of early typical MRI abnormalities.