Kleine-Levin Syndrome (“KLS”) is a rare sleep disorder characterized by recurrent and unusually long episodes of hypersomnia, associated with behavioral/cognitive disturbances, megaphagia and more rarely sexual disinhibition. These serious episodes alternate with periods without any symptoms, and normal sleep and behavior typically lasting months to years. KLS primarily strikes adolescents and is self-limiting; cessation of episodes typically occurs in early adult life.
The cause of KLS is unknown. All diagnostic test results on KLS patients to date, including brain imagery, EEG, serum virus titres, and CSF examination, have been normal. However, nearly half of the patients experience a non-specific, mainly flu-like infectious disease a few days before the onset of their first KLS episode. The rarity of KLS, compared to the high frequency of flu-like diseases in the general population, suggests that some patients may be more predisposed to KLS. This vulnerability may be genetic.
In KLS, the association of an infection before the onset of a disease, a young age at onset, a recurrence of symptoms and possible genetic predisposition is suggestive of an autoimmune disease. Various autoimmune diseases are tightly linked to a specific human leukocyte antigen (HLA) typing (this is a group that is not, like group A, B, O, on our red cells, but on our white cells). The immune system indeed distinguishes self-antigens from foreign antigens through the cell surface expression of the highly polymorphic HLA glycoprotein antigens. The HLA system (allele HLA-DQB1*0602) is highly associated with another sleep disorder, narcolepsy. It has been poorly studied in KLS patients, but a recent study in Europe yielded a higher than controls frequency of the HLA-DQB1*201 allele in 30 KLS patients, a group that has been associated with various autoimmune diseases. It is now necessary to extend and specify the measure to a much larger number of patients and families.
Strong evidence for an autoimmune basis in KLS could potentially lead to the testing of drugs or therapy aimed at reducing autoimmunity, which have not been yet, to our knowledge, tested in KLS. This is of particular interest in that severe disease where effective treatment is desperately missing. In addition, the questionnaire will provide the first large survey of the disease and its symptoms. It will also, when compared to questionnaires completed by non-affected healthy subjects, help identify commonalities between patients.
Our group (directed by Emmanuel Mignot, MD., PhD) at Stanford University will measure the HLA group and possible other genetic factors predisposing to KLS in all volunteer KLS patients, their parents and siblings, and compare it to the HLA group in age, sex and ethnic-matched controls. The study includes a questionnaire and blood sampling. The Kleine-Levin Syndrome Foundation (www.klsfoundation.org) funds in part this study and helps its realization.
Any patient who has ever been diagnosed with KLS, whether he/she still suffers from the disease or is now cured. There is no age limit. If you do not have a medical diagnosis but believe you have KLS, please contact our coordinator for involvement.
In addition, we appreciate both parents to give blood samples, too (it helps to better determine the HLA typing). Parent samples are a great help, and ideally we would hope to have samples from both parents to aid us. Siblings can also contribute samples, as this further helps our research.
Contact Dr. Emmanuel Mignot's lab at firstname.lastname@example.org so that we can explain the detailed procedure and check how it fits with you. Participation is not difficult, is done on your own time, and immensely helps further our research and understanding of KLS.
We pay for sending and returning the kit via FedEx. The hospital, clinic, or doctor's office where you have the blood drawn may charge you for the drawing procedure. Since that research is partly supported by a donation from the Kleine-Levin Foundation, participants may wish to absorb the cost of the blood draw if not a personal burden to enable further research. If this cost is an issue, you may request a reimbursement; we will need a written receipt for the blood-drawing service.
For some people, the blood drawing may cause bruising or small discomfort. In very rare cases, infection or fainting can occur. These are the risks always associated with a typcial blood draw. There is absolutely no risk for the blood drawing to bring on a KLS episode.