22q11.2 Microduplication syndrome and epilepsy with continuous spikes and waves during sleep (CSWS). A case report and review of the literature.

Chromosome 22q11.2 microduplication syndrome is characterized by a variable and usually mild phenotype and by incomplete penetrance. Neurological features of the syndrome may entail intellectual or learning disability, motor delay, and other neurodevelopmental disorders. However, seizures or abnormal EEG are reported in a few cases. We describe a 6-year-old girl with microduplication of chromosome 22q11.2 and epilepsy with continuous spikes and waves during sleep (CSWS). Her behavioral disorder, characterized by hyperactivity, impulsiveness, attention deficit, and aggressiveness, became progressively evident a few months after epilepsy onset, suggesting a link with the interictal epileptic activity characterizing CSWS. We hypothesize that, at least in some cases, the neurodevelopmental deficit seen in the 22q11.2 microduplication syndrome could be the consequence of a disorder of cerebral electrogenesis, suggesting the need for an EEG recording in affected individuals. Moreover, an array-CGH analysis should be performed in all individuals with cryptogenic epilepsy and CSWS.