Article

Kleine-Levin syndrome (KLS) is a rare, relapsing-remitting disease that affects
mostly adolescents. It is characterized by episodes lasting from 1 to several
weeks, and comprises neurological (hypersomnia, confusion, slowness, amnesia) and
neuropsychiatric symptoms (derealization and apathy).
Some psychiatric symptoms
(megaphagia, hypersexuality, anxiety, depressed mood, hallucinations, delusions)
arise during episodes, albeit less frequently, while patients are normal between
episodes. However, sudden severe (>18h/day of sleep) and recurrent hypersomnia
helps to differentiate KLS from other psychiatric mimics. Derealization, the
striking feeling of unreality or of being in a dream-like environment, is
strongly associated with hypoperfusion of the associative temporoparietal
junction cortex, whereas apathy is almost complete loss of autoactivation:
teenagers stop using their cell phones and their only spontaneous initiative is
to sleep. The cause of KLS is not known, but evidence suggests it could be a
recurrent inflammatory encephalitis. Up to 5% of cases are familial, although no
abnormal gene has yet been found. Hypersomnia episodes tend to become less
frequent and to disappear with advancing age. However, 28% of patients have
long-lasting episodes (>30 days), and around 15% have no signs of recovery after
>20 years of living with the disorder. Patients' cognitive and psychiatric status
should be regularly checked during asymptomatic periods, as 20-40% develop
long-term mild cognitive impairment or mood disorders. Lithium therapy is
beneficial for reducing episode frequency, and intravenous steroids can reduce
the duration of long episodes.
CI - Copyright (c) 2018 Elsevier Masson SAS. All rights reserved.

Langue : ANGLAIS