Adult-onset Rasmussen's encephalitis: Anatomical-electrographic-clinical features of 7 Italian cases

Purpose: A limited number of cases of adult-onset Rasmussen's encephalitis (A-RE) have been reported, but the features of the syndrome are still unclear. The aim of this study was to verify the clinical features of A-RE, and outline a noninvasive approach that may allow its early diagnosis and treatment. Methods: Retrospective evaluation of extensive noninvasive work-up of seven patients with A-RE, including repeat clinical, neurophysiological, and neuroimaging investigations. Results: The study identified two distinct patterns of disease presentation, one characterized by focal motor epilepsy (the "epileptic" phenotype), and the other by focal cortical myoclonus (the "myoclonic" phenotype). Unilateral neurological deficits and brain atrophy were progressive in both phenotypes, but they were more prominent and were detected earlier in the "epileptic" phenotype. Conclusions: The anatomo-electroclinical features of these patients allowed a noninvasive diagnosis of A-RE and identification of two distinct disease phenotypes. Early noninvasive diagnosis can allow faster initiation of treatment.