Late-onset epileptic spasms in a female patient with a CASK mutation

We report a female patient with late-onset epileptic spasms (ESs) of a rare form, distinct from those seen in typical West syndrome, in association with a heterozygous frameshift CASK mutation (c.1896dupC (p.C633fs(∗)2)). She has a phenotype of microcephaly with pontine and cerebellar hypoplasia (MICPCH), and has had intractable ESs in clusters since 3 years 8 months of age with multifocal, particularly bifrontal, epileptic discharges in electroencephalogram. The available literature on patients with both ESs and CASK mutations has been reviewed, revealing that four of the five female children, including the present girl, had late-onset ESs, in contrast to the four males, who tended toward early-onset ESs.