CASK pathogenic variant which expands the clinical spectrum for MICPCH syndrome in an adult patient.

The CASK gene and its product protein kinase have been associated with microcephaly with pontine and cerebellar hypoplasia (MICPCH) syndrome and various other neurodevelopmental disorders. Clinical presentation is highly variable and generally includes intellectual disability, neurological disorders, and dysmorphic features, at a minimum. We present the case of one of the oldest known currently living patients with MICPCH syndrome with additional features not previously described in the literature (midface retrusion, macroglossia, dental crowding, adolescent-onset contractures at large joints, laxity at finger joints, and prominent wrist dystonia). Progressive hypertonicity throughout the patient's life has been managed with serial botulinum toxin injections. A comprehensive multimodal care team including physiatry, physical therapy, exercise therapy, and audiology has been assisting her with hearing deficits, communication skills, and mobility. This potentially expands the phenotype of MICPCH syndrome and provides information about the management of this condition into adulthood.