Epileptic hypnagogic jerks mimicking repetitive sleep starts

Abstract

According to the International Classification of Sleep Disorders – Third Edition (ICSD-3), sleep starts, also called hypnic jerks, are classified as Sleep RelatedMovement Disorders and are listed among Isolated Symptoms and Normal Variants [1]. They are characterized by sudden, brief, nonperiodic contractions of one or more body segments, usually involving the trunk and all extremities simultaneously, representing a physiological and almost universal component of the sleep-onset process [2]. Sleep starts usually occur in isolation, in a spontaneous form or evoked by sensory stimuli. Although the differential diagnosis between sleep-related movement disorders and epilepsy has been thoroughly discussed [2], semiology overlaps, scant electroencephalography (EEG) correlates, and possible coexistence still pose diagnostic challenges. This is more so in pediatric neurology, given the peak incidence of nonrapid eyemovement sleep disorders during childhood. The following video-report illustrates the clinical and neurophysiologic characteristics of repetitive brief epileptic hypnagogic jerks, mimicking nonepileptic repetitive sleep starts.