R. Iorio1, G. Assenza2, G. Della Marca1, G. Colicchio1, M. Tombini2, V. Damato1, A. Benvenga2, A. Evoli1, D. Plantone1, A. Marti1, C. Vollono1, G. Frisullo1, A.P. Batocchi1
1Catholic University, 2Campus Bio-Medico University, Roma, Italy
Background: Autoantibodies specific for neural antigens have been described in association with several encephalopathies which have seizures as a prominent feature. In these cases seizures are poorly controlled with conventional anti-epileptic drugs (AED). In contrast, a good response is often achieved with immunotherapies.
Objectives: To evaluate the frequency of autoantibodies specific to neural antigens in patients with epilepsy and their response to the immunotherapy.
Materials and methods: Two groups of patients were included in the study: 29 patients with epilepsy and other neurological symptoms and/or autoimmune diseases (group 1) and 30 patients with AED-resistant epilepsy (group 2). Forty-two age and sex-matched healthy subjects (HS) were included as controls.
Patients' Serum and CSF, when available, were evaluated for the presence of neural autoantibodies by immunohistochemistry on frozen sections of mouse brain and by cell-based assays. GAD65-IgGs were tested by RIA.
Results: Neural-specific autoantibodies were detected in 11/59 patients (19%) but not in healthy controls. In particular, neural-specific IgGs were detected in two patients from group 1 (2/29, 7%) (anti-GAD65, 1; antibody specific for an unclassified intracellular antigen [AUIA], 1) and in nine patients from group 2 (9/29, 31%) (anti-LGI1, 2; anti-GAD65, 1; AUIA, 4; antibody specific for an unclassified synaptic antigen, 2). In Four patients from group 2, immunotherapy resulted in >50% seizure reduction at three months.
Conclusions: A significant percentage of patients with AED-resistant epilepsy harbor neural-specific autoantibodies and may respond to immunotherapy.

Assigned speakers:
Dr. Raffaele Iorio, Catholic University , Roma , Italy

Assigned in sessions:
22.09.2013, 09:00-10:30, Free Papers, FP1, Free Papers Session 1: Epilepsy, Hall G