1217 Narcolepsy in a Preschool-Aged Child

Abstract

The diagnosis of Narcolepsy in the pediatric population is a challenging process, and can result in unnecessary diagnostic work-ups and hospital admissions. 4-year-old African American female is admitted following an episode of “passing out” while on stage at a school dance rehearsal. A teacher described a 2-minute episode with “diffuse shaking” without incontinence, consciousness was preserved. She had a one-month history of excessive daytime sleepiness (EDS). An anti-epileptic drug was started, by her Pediatrician after presenting with periods of staggering, nonsensical speech, and enuresis. Mother also noted snoring and weight gain. An exhaustive work up was negative for seizures, autoimmune disease, stroke, CNS infection, or metabolic disease. She was treated for presumed autoimmune encephalitis with IV methylprednisolone and immunoglobulin. She developed visual hallucinations, but was discharged after resolution of all symptoms. A second admission with similar symptoms occurred a week later. Sleep Medicine was consulted and ordered an HLA DQ1B*0602 marker, which was positive. In-lab Polysomnography showed fragmented sleep with an Apnea-Hypopnea Index = 0.2/h, Total Sleep Time = 4.6 h, Sleep Latency = 55.5 min, REM Latency = 55.5 min, Sleep Efficiency = 53%, and Periodic Limb Movement Index = 0/h. The Multiple Sleep Latency Test was unremarkable with a Mean Sleep Latency = 12.8 min and Sleep-onset REMs = 0, but struggled to stay awake in-between naps. Finally, a cerebral spinal fluid sample was sent to the Center for Sleep Sciences at Stanford University, revealing a hypocretin-1 level of 0 pg/mL. This case demonstrates the challenges in diagnosing Narcolepsy, in the prepubescent population. EDS is usually the presenting symptom, but even with cataplexy, the diagnosis can be missed. Patients can be referred to multiple physicians, undergo overwhelming and lengthy work-ups, or be treated inadequately. Consulting a sleep specialist early in the clinical course may be of significant benefit.