Atypical case of hemiconvulsions-hemiplegia-epilepsy syndrome revealing contralateral focal cortical dysplasia.

Hemiconvulsions-hemiplegia-epilepsy syndrome (HH/HHE) is a rare epileptic syndrome consisting of a prolonged unilateral convulsion producing a persisting hemiplegia, sometimes followed by epilepsy. We report on a 13-month-old male who presented with febrile left-sided HH syndrome with right hemispheric unilateral cytotoxic oedema followed by hemispheric atrophy on magnetic resonance imaging (MRI). Six months later the child progressively developed refractory focal epilepsy, including right hemiclonic seizures, and nearly continuous left frontal rhythmic spikes, suggesting the presence of a focal cortical dysplasia (FCD). A repeat MRI at 2 years of age showed left frontal FCD. This unusual case of dual pathology--right HH syndrome and left FCD--suggests that some other factor than the malformation determined the prolonged status and brain atrophy. The kinetics of regional cortical maturation could explain this unusual condition.