The electroclinical pattern of 33 patients with familial, autosomal dominant, nocturnal frontal lobe epilepsy was studied, including video-polysomnographic monitoring in 12, at the University of Milano, School of Medicine, Italy. The syndrome is characterized by clusters of brief nocturnal motor seizures during sleep, beginning in childhood and persisting throughout adult life. The motor seizures during sleep varied from thrashing hyperkinetic activity to tonic extension with clonic movements. The most frequently repeated patterns included pelvic thrusting, facial grimacing and moaning, and dystonic posturing. Some had sudden elevation of the head and an expression of fear. Misdiagnoses included benign nocturnal parasomnias, including nightmares, night terrors, and somnambulism. Diurnal episodes in 58% included generalized shivering followed by loss of consciousness, and complaints of tingling and daytime sleepiness. Interictal and ictal EEGs showed nonspecific patterns (atypical K-complexes), or epileptiform abnormalities (in 58% of patients), consisting of bilateral or right frontal spikes, during stage 2 non-REM sleep. Normal EEGs were recorded during wakefulness. Both nocturnal and diurnal attacks were controlled by carbamazepine or clonazepam. [1]

COMMENT. Nocturnal frontal lobe epilepsy is often misdiagnosed as nightmares, night terrors, or somnambulism. Nocturnal paroxysmal dystonia is also considered in the differential diagnosis. EEGs are frequently nonspecific, and video-polysomnographic monitoring is often essential. If the diagnosis is suspected but unconfirmed by EEG, a trial of antiepileptic drugs may still be warranted.