Background: Wiedemann-Steiner Syndrome (WSTS) is a rare chromatinopathy caused by pathogenic variants in KMT2A. WSTS is characterized by neurodevelopmental disorders and distinct dysmorphic features. Epilepsy has been reported in only 33 individuals with WSTS, with only limited clinical details described.
Methods: We identified patients with pathogenic KMT2A variants and epilepsy, and performed thorough phenotyping.
Results: Five patients were identified, all of whom presented with developmental and epileptic encephalopathy (DEE). Epilepsy syndromes observed included Lennox-Gastaut syndrome [2], infantile epileptic spasms syndrome, and DEE with spike-wave activation in sleep. Seizure types observed included absence, generalized tonic-clonic, myoclonic, tonic, atonic, epileptic spasms, and focal seizures.
Conclusions: The spectrum of epilepsy phenotypes in patients with WSTS can be broad, but presentation is typically severe, usually involving a form of DEE.
Keywords: Continuous spike-wave in sleep; Developmental and epileptic encephalopathy; Infantile epileptic spasms syndrome; KMT2A; Lennox-gastaut syndrome; Wiedemann-Steiner syndrome.
© 2023 Published by Elsevier Ltd on behalf of European Paediatric Neurology Society.