A Novel WAC Loss of Function Mutation in an Individual Presenting with Encephalopathy Related to Status Epilepticus during Sleep (ESES)

WAC (WW Domain Containing Adaptor With Coiled-Coil) mutations have been reported in only 20 individuals presenting a neurodevelopmental disorder characterized by intellectual disability, neonatal hypotonia, behavioral problems, and mildly dysmorphic features. Using targeted deep sequencing, we screened a cohort of 630 individuals with variable degrees of intellectual disability and identified five WAC rare variants: two variants were inherited from healthy parents; two previously reported de novo mutations, c.1661_1664del (p.Ser554*) and c.374C>A (p.Ser125*); and a novel c.381+2T>C variant causing the skipping of exon 4 of the gene, inherited from a reportedly asymptomatic father with somatic mosaicism. A phenotypic evaluation of this individual evidenced areas of cognitive and behavioral deficits. The patient carrying the novel splicing mutation had a clinical history of encephalopathy related to status epilepticus during slow sleep (ESES), recently reported in another WAC individual. This first report of a WAC somatic mosaic remarks the contribution of mosaicism in the etiology of neurodevelopmental and neuropsychiatric disorders. We summarized the clinical data of reported individuals with WAC pathogenic mutations, which together with our findings, allowed for the expansion of the phenotypic spectrum of WAC-related disorders

Neuropsychological, clinical and eeg long term follow-up in six patients affected by continuous spike-waves during slow sleep

Epilepsia 2001, 42 (suppl 2): E-012

Acquired epileptic frontal sindrome as long term outcome in two children with CSWS

ontinuous spikes and waves during slow sleep (CSWS) are a well-known EEG pattern that can be associated with cognitive and behavioural deterioration. We present the long-term clinical, neuropsychological and EEG follow-up of two patients who developed CSWS during childhood. In both the CSWS onset was followed immediately by rapid cognitive and behavioural deterioration. Later the CSWS fragmented or fluctuated and the spike-wave discharges diminished and this was associated with progressive clinical improvement. At the same time bilateral frontal EEG abnormalities appeared awake and in sleep. After the initial period of rapid cognitive and linguistic improvement both patients stabilised. The latest neuropsychological assessment showed a frontal syndrome. The presence of frontal EEG abnormalities superimposed on CSWS, their persistence after CSWS resolution and, in addition, the finding of subtle frontal-type neuropsychological alterations early in recovery may indicate poor long-term outcome