Benign myoclonic epilepsy in infancy followed by childhood absence epilepsy

Benign myoclonic epilepsy in infancy (BMEI) is a rare syndrome included among idiopathic generalized epilepsies (IGE) and syndromes with age-related onset. Recently, it has been shown that a few patients with BMEI later had other epilepsy types mainly IGE but never childhood absence epilepsy (CAE). We report a patient who at 11 months of age showed isolated myoclonic jerks occurring several times a day. The ictal video-EEG and polygraphic recording revealed generalized discharge of spike-wave (SW) lasting 1-2s associated with isolated bilateral synchronous jerk involving mainly the upper limbs controlled by valproic acid (VPA). At 6 years and 8 months the child developed a new electroclinical feature recognized as CAE. The ictal EEG disclosed a burst of rhythmic 3 Hz generalized SW. Our case is the first patient with BMEI reported in the literature who later developed a CAE. This finding suggests a common neurobiological and genetic link between different age-related epileptic phenotypes.