A peculiar family with recurrent self-limited epileptic syndrome and associated developmental disorders in six girls

We describe a complex family with two couples (two sisters who married two brothers) with consistent social and neuropsychiatric problems, originally from Sardinia. Each couple had three daughters, which shared electroclinical epileptic syndrome and developmental disorders. All patients suffered from mild to moderate intellectual disability, speech difficulties and behavioural disorders. Four out of six patients had epilepsy onset between 3 and 4 years of age. The epileptic history almost reflected the typical clinical course of a self-Limited Focal Epilepsy of Childhood. However, our patients don’t have the complete features characteristic of one of the four specific self-Limited Focal Epilepsies of Childhood; a progressive evolution into a Developmental and/or Epileptic Encephalopathy with spike-wave activation in sleep was observed in the two older sister of the first family, which developed more severe developmental disorder too. In the other epileptic patients, improvement of EEG pattern was not coincident with an improvement of the developmental disorders. Brain MRI, performed in three patients, showed normal findings. Genetic analysis carried out so far (SNP-array, study of Runs of homozygosity, FMR1 triplet-repeat primer-PCR assay, Next Generation Sequencing based gene panel for epilepsy and neurodevelopmental disorders and Exome Sequencing), did not provide useful elements for an aetiological diagnosis.