THE KLEINE-LEVIN SYNDROME: A RARE DISEASE WITH OFTEN DELAYED DIAGNOSIS—A REPORT OF TWO CASES IN THE DEPARTMENT OF NEUROLOGY OF THE UNIVERSITY HOSPITAL OF COCODY (CÔTE D'IVOIRE)

Abstract

TheKleine-Levin syndrome (KLS)is classied among rare diseases[1, 2]. It belongs to the central hypersomnias said to be recurrent and dened according to the International Classication of Sleepiness Disorders, 3rd version (ICSD-3), revised in 2014. For the ICSD-3, the Kleine-Levin syndrome is a disorder characterized by recurrent episodes of hypersomnia andhyperphagia (rapidconsumptionof a large amountoffood),usually with onset in early adolescence inmales but occasionally in laterlife and in women.Amonosymptomatic form of the disorder with hypersomnia only can occur with- out binge eating or hypersexuality [1]. Usually affecting adolescent males, episodes normally last up to a few weeks and terminate with total and spontaneous recovery. Possibly rst reported by Brierre de Bosmont in 1862, the condition however received its name from Willi Kleinewho,in1925,reporteda seriesof casesofperiodichypersomnia and also Max Levin who described a case of periodic hypersomnia and excessive appetite in1930[2].The exactprevalence remainsunknown.But it seems very rare: around one to two cases per million. All cases are not published. A review of the inter- national literature of language between 1962and2004,byArnulf et al.[2], estimatedthenumberofpublishedcases at186.Accordingtotheseauthors,theannualincidencewas2.7in1970,3.5 in 1980, and 5.8 in the 1990s. For these authors, this growth would rather correspond to the extension ofthe globalscientic communication than an actual increase in the prevalence of the syndrome. Patients were described aroundtheworld,includingAsiaandAfrica,withcuriouslyone-sixthofthe world's cases described in Israel [1, 2]. Its etiology remains unknown. The genetic trail was discussed in the presence of familial cases [1, 2]. The diseasemainlyaffectsyoungmales[1,2].Itsdiagnosisisclinical[1,3,4].