Mowat-Wilson Syndrome; 3 Cases with Characteristic EEG Findings (P3-1.008)

Abstract

<h3>Objective:</h3> This is a case-based review of clinical manifestations and electroencephalogram findings of Mowat-Wilson Syndrome (MWS) <h3>Background:</h3> MWS is a rare multi system disorder due to ZEB2 gene defects. The main feature of MWS is epilepsy; 75–80% prevalence was noted in prior case series. <h3>Design/Methods:</h3> Children with known diagnoses of MWS were identified in the Pediatric Epilepsy Clinic attached to a tertiary-care pediatric hospital through retrospective chart review. Literature was searched with keywords ‘Mowat-Wilson Syndrome’ and ‘EEG features’ <h3>Results:</h3> Three children with MWS were identified. All cases were heterozygous for ZEB2 gene mutations and had brain imaging and electroencephalograms available for review. <h3>Patient A (11 year-old):</h3> Semiology was generalized and focal (oral automatisms and left-hand flapping). On electroencephalogram there was continuous 2–3 Hz spike-and-wave activity during sleep with left predominance (left frontal at first, but then involving the entire left hemisphere over the years), and intermittent 2.5–3 Hz high-voltage generalized spike-and-wave bursts during wakefulness <h3>Patient B (7 year-old):</h3> Semiology was generalized and focal (right-sided hypotonia and leftwards gaze). On electroencephalogram there were frequent 2–3 Hz poly-spike-and-wave discharges with left frontal-central predominance during sleep, and seizures stemming from right temporal and parieto-occipital areas during status epilepticus <h3>Patient C (4 year-old):</h3> Semiology was generalized. On electroencephalogram there were frequent bi-occipital sharp-and-slow-wave discharges as well as infrequent bursts of high-amplitude generalized 1–2 Hz spike-and-waves <h3>Conclusions:</h3> Electroencephalograms of 2 of 3 patients had continuous spike-waves in sleep (CSWS), even as seizure burden and semiology differed. While there was no CSWS in Patient C, there were sharp-and-slow-wave discharges during wakefulness. It is possible that due to Patient C’s younger age, the EEG has not progressed to develop full CSWS. Indeed, in Patient A, there was a clear progression of EEG abnormalities as the child grew older. This leads these authors to believe that CSWS seems to be distinctly common among Mowat-Wilson. <b>Disclosure:</b> Dr. Shahab has nothing to disclose. Dr. Anilkumar has received publishing royalties from a publication relating to health care.