The clinical manifestations and treatment of narcolepsy diagnosed in 51 prepubertal children (29 boys) are reported from the Stanford Sleep Disorder Clinic, Stanford University Medical Center, CA. The mean age was 8 years (range, 2 to 11). Diagnosis was based on daytime sleepiness as the initial symptom in 39, 10 presented with cataplexy, and 2 had hallucinations and sleep paralysis. In 5 patients who presented at or before 5 years of age, epilepsy was the first diagnosis considered; 3 reported abrupt unexplained falls, clumsiness, day dreaming, night terrors, and intermittent irritability and aggressiveness. The history of daily naps was obtained only after visits to 3 different specialists. Of 46 children older than 5 years, 36 were referred because of complaints from school: falling asleep in class, day dreaming, abrupt falling, and inattention. Attention deficit disorder was diagnosed in 10, hyperactivity in 12, epilepsy in 23, learning disability in 16. Behavioral and learning problems prompted examination by school psychologists or counselors in 39 children before the correct diagnosis was established. Cataplexy (sudden loss of muscle tone) was precipitated by laughter, but was accompanied by fear of embarrassment and was often concealed from peers and adults. It was sometimes partial and caused only knee buckling, head and shoulder dropping, jaw sagging, and slurred speech, and was usually preceded by excessive daytime sleepiness. Sleep paralysis and hypnagogic hallucinations occurred in two thirds, at least once a week, and sometimes nightly. Polysomnograms showed sleep-onset REM sleep in 31. Multiple Sleep Latency Tests showed a mean sleep latency of 1.5 min +/- 39 secs; all children had 2 sleep-onset rapid eye movement sleep episodes in this test. HLA class II serotyping was positive for DQw6 in 46 children, and for DRwl5 in 45. EEGs were “unremarkable,” except for rapid onset of sleep. MRI in 14 and CT in 3 were normal. IQ mean score was 96 +/- 11. Drug treatments included pemoline, methylphenidate, clomipramine, and fluoxetine; poor compliance was common, particularly after 7 years of age. Depressive reactions related to the illness, withdrawal from social interaction, poor self-esteem, and inadequate teacher understanding required psychological intervention. [1]

COMMENT. Narcolepsy is uncommon during childhood, accounting for about 5% of cases attending a specialty clinic. The diagnosis is often delayed, and symptoms are mistaken for epilepsy, attention deficit disorder, learning and behavior problems. Early pharmacotherapy and counselling are recommended to prevent depressive reactions, school failures, and poor peer relationships. Delay in treatment results in irregular school attendance, academic failure, and poor self-esteem.