Abstracts

Among temporal lobe epilepsies, some authors have defined a so-called mesio-temporal lobe epilepsy syndrome (MTLE), based on electro-clinical, radiological and pathological criteria. In a cohort of non-tumoral adult patients with temporal lobe epilepsies not filling the criteria of MTLE, we have assessed the possibility of an autoimmune component. All patients underwent neuropsychological examination, long-term video-EEG monitoring, high-resolution MRI and laboratory analysis including anti-thyroid antibodies and exhaustive screening of autoimmunity. We have identified twenty patients with high levels of autoantibodies to thyroid peroxydase and/or thyroglobulin (33 times higher than the upper limit of normal range). They differed from classical MTLE : female predominance (90%), no history of febrile seizures (95%), age at onset above 18 years-old (95%, average 37 years, range 15-71 years), bilateral independent seizures or EEG abnormalities (50%). 65% of patients had other marks of autoimmunity (i.e. antinuclear antibodies...). Two patients could be classified as Hashimoto[apos]s encephalopathy. MRI highlighted unilateral (n=6) or bilateral (n=2) hippocampal sclerosis, multiple cortical and/or sub-cortical bilateral lesions (n=3), transient focal abnormalities (n=2) and was normal or non specific in the remaining 7 patients. Seven patients (35 %) had a drug-resistant epilepsy and some of them were treated with corticosteroids (n=4) or immunoglobulins (n=1). In late-onset non tumoral temporal lobe epilepsies, detection of anti-thyroid antibodies should be considered, with the aim to assess corticosteroids in case of antiepileptic drug-resistance, since steroids were reported to be valuable in the most serious cases like Hashimoto[apos]s encephalopathies. The prevalence of autoimmune marks during focal epilepsies and their pathological significance remain to be studied.