Williams-Beuren syndrome is rarely associated with epilepsy. One previously reported case showed an association with apnoeic seizures while a few other cases showed an association with infantile epileptic spasms and generalized and focal seizures. We report the case of a 13-month-old boy with a deletion typically associated with Williams-Beuren syndrome, who presented with isolated apnoeic seizures which were refractory to multiple antiepileptic drugs but partially responsive to the ketogenic diet. The diagnosis was challenging due to a complex cardiac history, gastroesophageal reflux, and normal interictal EEG findings. This case highlights the importance of prolonged EEG monitoring in suspected cases of apnoeic seizures. Further, given the reported cases of unexplained sudden death in Williams-Beuren syndrome, this case raises the possibility of an association between apnoeic seizures and unexplained sudden death. [Published with video sequence on www.epilepticdisorders.com].
Keywords: Brief Resolved Unexplained Event; SUDEP; apnoea; cyanosis; epilepsy.