Musicogenic reflex seizures in epilepsy with glutamic acid decarbocylase antibodies.

BACKGROUND: Musicogenic reflex seizures (MRS) are a rare form of seizures described in patients with temporal lobe epilepsy (TLE), mainly of unknown etiology. Epilepsy with antibodies against glutamic acid decarboxylase (GAD-ab) is a form of autoimmune epilepsy for which no specific semiology has been described.

AIM OF THE STUDY: To retrospectively review the incidence of MRS in the general epileptic population and in the series of patients with epilepsy and GAD-ab and to describe its clinical and paraclinical characteristics.

METHODS: Patients recorded between January 2010 and January 2016 in the Database of Bellvitge Hospital Epilepsy Unit were reviewed.

RESULTS: From a group of 1510 epileptic patients, three reported MRS (0.0019%) (two patients with epilepsy and GAD-ab and one patient with cryptogenic TLE). The incidence of MRS in patients with epilepsy and GAD-ab was 2 of 22 (9%). Both patients had a normal magnetic resonance Imaging (MRI), but FDG-PET showed medial temporal lobe hypometabolism (unilateral or bilateral) in both and also in the insula in one of them. MRS (recorded via video-EEG[electroencephalography] in one patient) arose from the right temporal lobe.

CONCLUSIONS: MRS may be a distinctive seizure type in patients with epilepsy and antiGADab. Determination of GAD-ab should be carried out in all cases of MRS, even those with normal structural MRI.