Hypocretin deficiency develops during onset of human narcolepsy with cataplexy.

Study Objectives: Although hypothesized through animal studies, a temporal and causal association between hypocretin deficiency and the onset of narcolepsy with cataplexy (NC) has never been proven in humans.

Setting: Paediatric Department, Blekinge Hospital, Sweden, and Danish Center for Sleep Medicine, Glostrup Hospital, Denmark.

Patient And Results: Two weeks after his second Pandemrix-vaccination, a 10 year old HLA-DQB1*0602-positive boy developed NC.