Kleine-Levin Syndrome (Orphanet)

In August 2008, Orphanet published a document compiled by Professors Arnulf, Lecendreux, Franco and Dauvilliers, specialised in neurology and sleep pathologies. This report deals with the characteristics of the Kleine-Levin Syndrome.

It is a very rare neurologic disease (1 or 2 cases out of 1 million) which results mainly in episodes of hypersomnia and loss of the sense of reality. Treatments are quasi-non-existent and not very effective, which makes it difficult to deal with it.

Characteristics of the Kleine-Levin Syndrome


  • This document of Orphanet lists the main symptoms of Kleine-Levin Syndrome:
    • Hypersomnia,
      • The patient sleeps between 18 and 24 hours per day,
      • Sleep disturbed by intense dreams and hallucinations,
    • Cognitive disorders,
      • Difficulty of expressing themselves and of concentrating on reading,
      • Cannot take definite choice or carry out 2 actions at the same time,
      • Temporal and space confusion, partial amnesia,
    • Feeling a loss of the sense of reality,
      • Feeling of disconnection between the body and the spirit,
      • Impression of being "in a dream",
    • Behavioral and psychic disorders
      • Hyperphagia,
      • Sexual dishinibition,
      • Irritability and apathy,
      • Suicidal desire,
      • Meningitis symptoms: cephalgia, photophobia, fever, nauseas.

Induced and worsening factors

  • Factors of vulnerability:
    • Male sex (2/3 of the patients),
    • Perinatal problems or of development,
    • Patient of Ashkenazi origin.
  • Starting factors:
    • Season: autumn and winter,
    • Influenza and angina,
    • Alcohol, unusual stress,
    • Infectious agents: Asian flu, chickenpox, streptococcus,
    • Cranial trauma,
    • Use of marijuana,
    • School holidays or respite after a period of examination.

Other forms of the syndrome

  • SKL (Kleine-Levin Syndrome) idiopathic, without another symptom before the disease or apart from the crises.
  • People suffering from another serious neurological disease.
  • Benign forms during which only two to three episodes take place without continuation.
  • Serious forms because of their frequency or the duration of the episodes.

Evolution of the disease

  • Normal state at the end of the episode.
  • The duration of an episode varies from two to 270 days.
  • Between the episodes, the periods of respite last an average of 3,5 to 4 months.
  • Cures spontaneously in the large majority of the cases.
  • Does not concern vital prognosis.

Causes, treatment and advices

Almost unknown factors

  • The authors of the document explain that the causes of the syndrome are not studied much:
    • No virus was identified,
    • Hypothesis:
      • Prematurity,
      • Delay in the development of the child,
      • Epilepsy,
      • Autism,
      • Ashkenazi Jewish origin.

Treatment and advices

  • The majority of the treatments are disappointing, but some were beneficial for isolated cases:
    • Somnolence: amantadine at the beginning of an attack,
    • Psychotic symptoms: Risperidone,
    • Distress: anxiolytic,
    • Treatment with lithium or sodium valproate in case of recurrence.
  • Advice:
    • Prevent the patient from driving a car,
    • If brutal depressive symptoms appear, make sure of the proximity of a family member,
    • Avoid drinking alcohol,
    • An assessment of sleep and brain scan by a SISCOM process.


The Kleine-Levin syndrome, Orphanet, August 2008.

Photographic copyright: Elifranssens - Dreamstime.com
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