Genetic Generalized Epilepsies: Phenotypic Definition, Neurophysiological Characterization, and Outcome Prediction Models

Autoimmune Encephalitis (AE) is a novel clinical entity,
characterized by the subacute onset of mental status
alterations, cognitive impairment, behavioral disorders and
epileptic seizures, which often represent the first sign at
disease onset. These manifestations, suggestive for limbic
involvement, may be accompanied by movement and sleep
disorders and dysautonomia. The wide phenotypical variability,
the existence of formes frustres and the lack of supporting
laboratory/neurophysiological/neuroimaging evidence in a
considerable proportion of cases, make the diagnosis
particularly challenging, especially in the elderly. As to AE
pathophysiological basis, it apparently depends upon
alterations of the complex mechanisms of adaptive immunity,
sometimes related to prior infectious conditions or underlying
neoplasms, and is associated to specific autoantibodies in
about 50% of cases. The prompt start of immunotherapy is
crucial to improve the outcome of AE patients, who might
develop cognitive and psychiatric sequelae and a temporal
lobe epilepsy (as reported in 10-15% of cases), often drug-
resistant. Therefore, AE represents a unique model to
investigate the fascinating interactions between ictogenesis,
epileptogenesis and immunity.
This research aims to the thorough phenotypic characterization
of AE patients, with specific focus on acute symptomatic
seizures and autoimmune-associated epilepsy. In the context
of an extensive evaluation, based upon personal data
collection, neurological examination and clinical scales, a
careful analysis of paroxysmal phenomena observed during
AE will be performed: namely, epileptic seizures, movement
disorders and parasomnias. In particular, a detailed
semiological analysis of seizures occurring during both the
acute and the chronic stage is required in order to identify
features suggestive for the immune etiology of late-onset
seizures, and distinguish them from those observed in patients
with temporal lobe epilepsy related to other causes. Moreover,
the systematic evaluation of polygraphic EEG/Video-EEG
exams performed during wake and sleep will allow the
identification of: 1) ictal and interictal EEG findings suggestive
for AE, 2) EEG features pathognomonic of specific forms, 3)
sleep structure alterations. The careful collection and revision
of clinical features, laboratory, neurophysiological and
neuroimaging (brain MRI) findings will aim to outline possible
antibody-specific syndromes and identify prognostic factors of
drug-resistant temporal lobe epilepsy. Besides, the revision of
the historical AE cohort and the longitudinal observation of
newly diagnosed patients, whose outcome will be defined
through a multi-dimensional approach, will be performed to
conceive a therapeutic algorithm, which will be validated in
future studies