Electrical status epilepticus during sleep in a child with Prader-Willi syndrome: a case report.

Prader-Willi syndrome (PWS) is a rare and complex genomic imprinting disorder caused by an absence of expression of paternal genes from chromosome 15q11.2-q13. Clinical manifestations of PWS depends on age. In early infancy, PWS patients is characterized by hypotonia and failure to thrive. Later in life, they can also exhibit hyperphagia, obesity, short stature, hypogonadism, behavioral issues and cognitive disability. Multiple sleep abnormalities including obstructive and/or central sleep apnea, daytime hypersomnolence, and impaired responses to hypercapnia and hypoxia have been described in patients with PWS. Recent studies also demonstrated an increased risk of seizures in PWS patients. Electrical status epilepticus in sleep (ESES) is an age-limited epilepsy with various seizure types, neurophysiological and motor impairment. The classic electroencephalogram (EEG) pattern of ESES involves continuous epileptic activity at 2-3 Hz occupying greater than 85% of non-rapid eye movement (REM) sleep. Treatment of the ESES syndrome consists of anti-epileptic drugs in routine cases, and corticosteroids, gamma globulins, the ketogenic diet, and surgery in refractory cases. In this project, we describe ESES during polysomnography in a 5-year-old female with PWS and no history of seizure disorder. To the best of our knowledge, this is the first case report on ESES in a PWS patient.