Abstracts

Rationale: Koolen-de Vries Syndrome (KdVS) is a rare genetic syndrome caused by a 440-680-kb deletion in the 17q21.31 region or by an intragenic KANSL-1 mutation. KdVS involves different organ systems and is characterized by intellectual disability and dysmorphic facial features. These patients may also have cardiac, renal/urologic and dermatologic abnormalities. About 50% of these patients have seizures. Both focal and generalized onset seizures have been described. Typical clinico-electrographic findings are multifocal epileptiform discharges and seizures with prominent autonomic features. We describe an 18 year old non-verbal man with Koolen de Vries syndrome and history of epilepsy admitted with myoclonic episodes seen in the awake period. At the time of the admission to the Pediatric Epilepsy Monitoring Unit, he was being treated for epilepsy with levetiracetam, with documented seizures in the past with a semiology suggestive of generalized tonic-clonic seizures. During the electroencephalogram (EEG), multiple typical episodes were recorded with no electrographic abnormalities but a clinical semiology consistent with that of myoclonic seizures. Methods: Patient was admitted for a 24 hour video EEG. The episodes were frequent, with multiple episodes recorded in this time period. Results: A 24 hour video EEG failed to show ictal or interictal abnormalities despite the patient having multiple typical myoclonic episodes. Brief periods of muscle artifact was seen each time the patient had myoclonus. His levetiracetam was not stopped during the hospitalization. The episodes resolved when the patient went to sleep. Patient was discharged home with no changes in his home dose of the levetiracetam with a diagnosis of non-epileptic spells. Conclusions: Koolen de Vries is a rare genetic syndrome associated with intellectual disability and epilepsy in about half of the patients. The epilepsy is not clearly defined in these patients, but recent reports suggest multifocal epileptiform abnormalities and seizures with prominent autonomic features and history of status epilpeticus. Our patient had non-epileptic spells and to the best of our knowledge non-epileptic spells have not been reported in this syndrome. Our patient was non-verbal and had severe intellectual disability. Therefore, the etiology of these episodes could not be explained based on history and physical examination. This case illustrates the point that events concerning for epileptic seizures should be evaluated with continuous EEG in patients with this syndrome before medication doses are adjusted, since some of them could present with non-epileptic spells mimicking epileptic seizures. References: 1) Koolen-de Vries Syndrome Clinical Report of an Adult and Literature Review Ciaccio C, Dordoni C, Ritelli M, Colombi M. Cytogenet Genome Res. 2016;150(1):40-45. doi: 10.1159/000452724. Epub 2016 Nov 17 2) The epileptology of Koolen-de Vries syndrome: Electro-clinico-radiologic findings in 31 patients. Myers KA, Mandelstam SA, Ramantani G, Rushing EJ, de Vries BB, Koolen DA, Scheffer IE. Epilepsia. 2017 Jun;58(6):1085-1094. doi: 10.1111/epi.13746. Epub 2017 Apr 25 Funding: None