Apparent resolution of hypersomnia episodes in two patients with Kleine-Levin syndrome following treatment with the melatonin receptor agonist ramelteon

Kleine-Levin syndrome (KLS) is a rare disorder characterized by episodic bouts of severe hypersomnia associated with cognitive and behavioral abnormalities and normal alertness and functioning in between episodes. The pathophysiology is unclear but may involve neurotransmitter abnormalities, hypothalamic/thalamic dysfunction, viral/autoimmune etiology, or circadian abnormalities. No single treatment has been shown to be reliably efficacious; lithium has demonstrated the most consistent efficacy, although many do not respond and its use is limited by side effects. Due to the evidence of circadian involvement, we hypothesized that strengthening circadian signals may ameliorate symptoms. Ramelteon is a potent melatonin receptor agonist. In this report, two patients with KLS are described with apparent resolution of hypersomnia episodes following ramelteon initiation.

CITATION

Dominguez D, Rudock R, Tomko S, Pathak S, Mignot E, Licis A. Apparent resolution of hypersomnia episodes in two patients with Kleine-Levin syndrome following treatment with the melatonin receptor agonist ramelteon. J Clin Sleep Med. 2024;20(4):657-662.

Idiopathic hypersomnia and Kleine-Levin syndrome

Idiopathic hypersomnia (IH) and Kleine-Levin syndrome (KLS) are rare disorders of central hypersomnolence of unknown cause, affecting young people. However, increased sleep time and excessive daytime sleepiness (EDS) occur daily for years in IH, whereas they occur as relapsing/remitting episodes associated with cognitive and behavioural disturbances in KLS. Idiopathic hypersomnia is characterized by EDS, prolonged, unrefreshing sleep at night and during naps, and frequent morning sleep inertia, but rare sleep attacks, no cataplexy and sleep onset in REM periods as in narcolepsy. The diagnosis requires: (i) ruling out common causes of hypersomnolence, including mostly sleep apnea, insufficient sleep syndrome, psychiatric hypersomnia and narcolepsy; and (ii) obtaining objective EDS measures (mean latency at the multiple sleep latency test≤8min) or increased sleep time (sleep time>11h during a 18-24h bed rest). Treatment is similar to narcolepsy (except for preventive naps), including adapted work schedules, and off label use (after agreement from reference/competence centres) of modafinil, sodium oxybate, pitolisant, methylphenidate and solriamfetol. The diagnosis of KLS requires: (i) a reliable history of distinct episodes of one to several weeks; (ii) episodes contain severe hypersomnia (sleep>15h/d) associated with cognitive impairment (mental confusion and slowness, amnesia), derealisation, major apathy or disinhibited behaviour (hypersexuality, megaphagia, rudeness); and (iii) return to baseline sleep, cognition, behaviour and mood after episodes. EEG may contain slow rhythms during episodes, and rules out epilepsy. Functional brain imaging indicates hypoactivity of posterior associative cortex and hippocampus during symptomatic and asymptomatic periods. KLS attenuates with time when starting during teenage, including less frequent and less severe episodes. Adequate sleep habits, avoidance of alcohol and infections, as well as lithium and sometimes valproate (off label, after agreement from reference centres) help reducing the frequency and severity of episodes, and IV methylprednisolone helps reducing long (>30d) episode duration.

[Kleine Levin syndrome: Review of diagnosed cases of Buenos Aires, Argentina]

Kleine-Levin syndrome is an uncommon disorder with recurrent episodes of hypersomnia, and behavioral abnormalities such as binge-eating and hypersexuality. Our aims were to report cases of the Kleine-Levin syndrome diagnosed in Buenos Aires, Argentina and to characterize the clinical presentation of these patients. We evaluated patients with Kleine-Levin syndrome according to the International Classification of Sleep Disorders. Psychiatric, physical and neurological symptoms were present. Some patients were investigated with brain Magnetic Resonance Imaging, Single Photon Emission Computed Tomography, electroencephalogram and some with polysomnography. Seven patients (2 female, 5 male), ages from 8 to 47 years (median 20.7 years) were included in the study. The duration of symptoms was 1.5-20 days with a mean of 8. The range of interval between episodes: 2.5-24 months, median=13. All seven patients had a history of hypersomnia (one of them post head injury); 5 reported hyperphagia and 2 reduced appetite. Brain MRI was performed in 6 patients: 1 showed non-specific abnormalities and another presented diencephalic hematoma; the rest were normal. Our paper is the first one in Buenos Aires reporting Kleine-Levin syndrome of different ethiologies. The prevalence is difficult to estimate in our country.

A Case of Kleine-Levin Syndrome: Diagnostic and Therapeutic Challenge

Kleine-Levin syndrome (KLS) is a rare sleep disorder mainly affecting teenage boys in which the main features are intermittent hypersomnolence, behavioral and cognitive disturbances, hyperphagia, and in some cases hyper sexuality. Etiology is unknown, and there is no specific clinical or imaging test for this syndrome even though the illness has well-defined clinical features. Also, there is no effective treatment for KLS. KLS is self-limited, so the prognosis for these patients is not so bad. This study presents our case report and comprehensive workout that led to diagnosis which is primarily clinical. Our patient is a 20-year-old man referred to our clinic because of sleeping problems. At the age of 14, he presented with complaints of the excessive duration of sleep, increased appetite, excessive daytime sleepiness, loss of interest in social activities during attendance of high school and hallucinations. The excessive diagnostic procedure does not find pathological. Kleine-Levin syndrome (KLS) is a rare sleep disorder of unknown etiology which diagnosis is clinical and diagnostic workup is mainly to exclude other similar conditions. There is no specific therapy, but the disease is self-limited and with good prognosis.

Kleine-Levin Syndrome

Kleine-Levin syndrome (KLS) is a rare disorder characterized by discrete episodes of hypersomnia associated with cognitive and behavioural abnormalities, as well as normal alertness and function between episodes. The prevalence of KLS may be underestimated as it is often misdiagnosed and managed as another sleep disorder, neurological disorder or psychiatric condition. KLS is more typically seen in adolescence than at other ages, and is more common in males than in females. There are currently neither standard biomarkers nor specific imaging study findings, making the diagnosis of KLS a challenge. Furthermore, there are no consistently effective therapies. The prognosis, however, is felt to be overall favorable, as episodes become progressively milder and less frequent before resolving entirely in most patients.

[Clinical presentation of Kleine-Levin syndrome]

Objective: To analyze the clinical features of Kleine-Levin syndrome (KLS) patients. Methods: Clinical data of 44 patients with KLS of the Sleep Center of Peking University People's Hospital from January 2002 to July 2013 were systematically reviewed. The predisposing factors and clinical presentations were summarized, and compared with the data from a Western KLS study with a large subjects number. Nocturnal polysomnography (PSG) and multiple sleep latency test (MSLT) were conducted during relapse and remission period, respectively. HLA-DQB1*0602 gene were screened and analyzed. Results: Among the 44 patients, 28(63.6%) were men and 16(36.4%) were women, with a mean age of (18.3±8.9) years old. Most patients developed the symptoms during adolescence. Infection or fever was the most common trigger for episode. The main clinical presentations were 44(100.0%) hypersomnia, 31(70.5%) forgetfulness, 26(59.1%) decreased appetites, 24(54.5%) juvenile behavior, 18(40.9%) depression, etc. Compared with the Western study, it showed that our patients had decreased instead of increased appetite. The PSG testing did not have remarkable findings. MSLT showed mean sleep latency was significantly shorter during relapse than during remission [(10.4±5.4) vs (15.3±3.4) min, P=0.009]. HLA-DQB1*0602 was positive in 12 of 40(30.0%) patients, which was similar to the data in the Chinese population. Conclusions: KLS has various clinical characteristics. The presentation of appetite may be different between Chinese and western KLS patients.

[Kleine-Levin syndrome: differential diagnosis in recurrent encephalitic syndromes in adolescence]

INTRODUCTION

The Kleine-Levin syndrome is a rare disease of unknown origin characterized by recurrent and self-limited episodes of hypersomnia that are also accompanied by a cognitive and behavioral dysfunction. Patients present normal sleeping and behavior patterns between episodes.

CASE REPORTS

We present three patients who are 14 years old: two boys and one girl. They started having the episodes after a predisposing factor (vaccine, influenza B and menstruation). During the episode they presented hypersomnolence and while wakefulness they were bradipsychic, in motor restlessness and with emotional liability. They also presented a tendency towards crying and claimed the presence of relatives constantly. The episodes lasted between 10 and 15 days and they appeared monthly, being asymptomatic between episodes. All three patients were attended initially by pediatricians, diagnosed and treated as autoimmune encephalitis. Only one of our cases had the three typical symptoms of hypersomnia, hyperfagia and hypersexuality. However, none of the three had been asked initially and the family only referred to it after the directed anamnesis.

CONCLUSIONS

The Kleine-Levin syndrome presents neurologic symptoms initially more frequently than psychiatric ones. Hypersomnia and behavioural disturbances during wakefulness, bradypsychia, apatheia and emotional liability make us suspect that it could be an encephalitis process. We should be aware of this entity if we face a patient with recurrent encephalitis of unknown origin.

[A young boy with periodic strange behavior and hypersomnia: Kleine-Levin syndrome]

Kleine-Levin syndrome is a rare neuro-psychiatric disease. Most of the young patients are males who present with hypersomnia, cognitive dysfunction, altered perception, eating disorder (e.g. hyperphagia) or disinhibited behaviour (e.g. hypersexuality). Psychiatric symptoms such as apathy, delusions and hallucinations, depressed mood and compulsive behaviours also appear often and result frequently in a psychiatric referral. These symptoms, however, should be distinguished from those of psychiatric diseases as early as possible in order to ensure that patients do not receive the wrong treatment. We present the case of an 11-year-old boy in whom the psychiatric symptoms were initially the most prominent ones.

Kleine-Levin Syndrome: An Overview and Relevance to Nursing Practice

Kleine-Levin syndrome (KLS) is a neuropsychiatric sleep disorder primarily affecting adolescent males. Onset is insidious, idiopathic, and hastened by neurological incident or infection. Typically, the initial onset occurs during the teen years or after the second decade, although cases have been documented in early childhood, adulthood, and senescence. KLS is marked by unexpected debilitating, yet reversible, episodic hypersomnia, with varying recurrence rates; cognitive and behavioral impairment; compulsive eating; and feelings of derealization, hypersexuality, apathy, and depressed mood. Diagnosis is problematic due to the syndrome's rarity, disparity of presenting clinical symptoms, and misdiagnosis. Correct diagnosis can take up to 4 years. The clinical course is approximately 8 to 14 years from initial onset, yet may be longer in the adult form of the disorder. KLS has been shown to impact activities of daily living, usurping an adolescent of his/her social relations with peers, experiences, and time.

[Kleine Levin Syndrome: more than just periodic hypersomnia]

BACKGROUND

Kleine Levin Syndrome (KLS) is a rare disease with periodic hypersomnia as its main feature. Hyperphagia and hypersexuality are also described as classical symptoms, although quite recently it has become clear that the full triad is absent in the majority of patients.

CASE DESCRIPTION

A 14-year-old boy developed KLS after a period of flu-like symptoms. Over the course of three years he suffered from seven one-week episodes of extreme hypersomnia (sleeping 18 hours a day), depersonalisation, apathy, anxiety, paranoia, confusion, hallucinations and uninhibited sexual behaviour. He ate little. Ancillary investigations did not reveal any abnormalities. In between these episodes he had no symptoms.

CONCLUSION

From this case description and a summary of the symptoms of twelve other patients with KLS, it appears that neuropsychiatric symptoms are much more prominent than hyperphagia and hypersexuality. It is important that the typical KLS phenotype be reappraised, so that the condition can be recognised early and patients managed appropriately.

[Kleine-Levin syndrome is a diagnostic challenge]

Kleine-Levin syndrome (KLS) is a rare disorder characterized by recurrent episodes of hypersomnia, disturbed behaviour, and cognitive function; it may by accompanied by hyperphagia/hypersexuality. KLS is often seen after a minor infection in young men but the aetiology is unknown. This case rapport illustrates how a 16-year-old boy with ADHD presented with a range of the above-mentioned symptoms and was assessed by neurologists, internal medicine doctors and psychiatrists. After two new episodes he was finally diagnosed with KLS. The understanding of this disorder is intriguing.

Kleine Levin syndrome in Malaysia: first typical case

A 13-year-old boy presented with a 2 weeks history of tearfulness, childish behaviour, separation anxiety, hypersomnia, hyperphagia and sexual disinhibition following a brief episode of fever. He had been experiencing the episodes since he was seven. The episodes lasted from a few days to 3 weeks and would normally occur once in a year. Most of the time it started with fever and resolved spontaneously. In the past he described auditory hallucination but not this time. Examination revealed a slightly overweight adolescent male appearing appropriate to his age. During the session he was restless, sleepy and burst into tears frequently. He constantly asked his mother when he could go home to sleep. He was very childish and clung to his mother. He was given a trial of risperidone 1 mg to be taken once a day for 3 days. On follow-up he had completely recovered.

First attack of Kleine-Levin syndrome triggered by influenza B mimicking influenza-associated encephalopathy

Six days after the onset of influenza B symptoms, a 14-year-old Japanese boy presented with encephalopathy-like symptoms, somnolence, irritability, and childishness, which we first considered was an atypical type of influenza-associated encephalopathy because the infection symptoms disappeared by day 4. His encephalopathy-like symptoms gradually improved, although he had repetitive hypersomnia attacks. Owing to the patient's clinical presentation and normal interleukin-6 levels in the cerebrospinal fluid during the first period of hypersomnia, we diagnosed him with Kleine-Levin syndrome (KLS) triggered by influenza B. The preceding influenza infection was not only a diagnostic clue of KLS but also a diagnostic confounding factor.

Kleine-Levin syndrome: the first typical case in Thailand

Kleine-Levin syndrome (KLS) is a rare disorder characterized by periodic hypersomnia, cognitive and behavioral disturbances. Other unique symptoms in KLS are megaphagia, hypersexuality and some psychiatric disturbances such as compulsion and depression. Definite diagnosis requires the elimination of other potential etiologies. We reported a typical case of KLS in a young Thai man who suffered from seven episodes of periodic hypersomnia within 1.5 years and eventually he was diagnosed with Kleine-Levin syndrome after excluding known possible neurological conditions and sleep disorders.

Onset of Kleine-Levin Syndrome in association with isotretinoin treatment

The synthetic retinoid isotretinoin is an effective treatment option for severe forms of acne vulgaris. However, several reports indicate that some patients experience altered central nervous system functions in association with treatment. We present here the first description of the onset of Kleine-Levin Syndrome (KLS), a rare disorder characterised by periodic hypersomnia and cognitive and behavioural symptoms, in close temporal relation to the start of isotretinoin treatment. We also discuss the biological potential of retinoids to affect sleep.

CONCLUSIONS

In light of a documented potential of retinoids to modulate sleep-wake regulation, the present case suggests that isotretinoin may rarely trigger the onset of KLS.

Kleine-Levin syndrome: current status

Kleine-Levin Syndrome is a periodic hypersomnia characterized by recurrent episodes of hypersomnia and other symptoms. This article reviews the research to date, outlines the clinical symptoms, and describes current testing and treatment. It concludes that the cause remains unknown and no treatment is effective in preventing recurrence, although modafinil may reduce duration of symptomatic episode.

[Kleine-Levin syndrome: a case report]

The purpose of this article is to report an original clinical case whose symptoms suggest a very peculiar pathology, because of its rarity, symptomatic expression and unclear etiopathogenesis: the Kleine-Levin Syndrome (KLS). During the regression of tonsillitis concomitant with an emotional shock, the 15-year-old patient exhibited a dramatic change in behaviour, at odds with his previous state, and accompanied by hypersomnia and confusion, megaphagia, irritability, hypersexuality and mood disorders. We observed a spontaneous and total regression of the symptoms after 12 days, except for the incomplete amnesia that proved to be persistent. Four months later, further to an ethylic drunkenness, the patient presented with a new and similar episode. The patient benefited from no medicinal treatment, even in the course of hypersomnia episodes and asymptomatic periods. After a clinical presentation of this patient, we will consider this case study from a more psychopathological angle by questioning the existence of a facilitating psychological profile. The discovery of an IQ equal to 86 from the scores of WISC-IV, and the identification of constructive visual difficulties made us suspect neurological disorders, but these abnormalities were not found during the completion of the Rey Complex Figure Test. The personality profile issued from the scores at the MMPI-A assessment was ranked as barely significant (type 2-4): indeed, it showed nothing specific to this patient. Literature data show that most of the patients presenting with a KLS have been seen by a psychiatrist at the time of the disease and diagnosed as suffering from hysteria, or schizophrenia, or bipolar disorders... Because of diagnostic wanderings, some patients have, hence, received inappropriate treatments. One should pay close attention to this very rare syndrome, on the border between neurology and psychiatry, since its diagnosis is essentially based on clinical features, and carefully think about the implementation of a medicinal treatment. This unique case seems unable to support our working hypothesis about the identification of a particular psychological profile in the KLS, but the question of an underlying fragility is still worth considering. We personally think that, even though links between the KLS and bipolar disorders have been suggested, this disease has to be considered as a separate entity.

Gabapentin for Kleine-Levin syndrome

We describe a 17-year-old girl with Kleine-Levin syndrome (KLS), in which gabapentin was effective for the prevention of attacks. (99)mTc-ECD SPECT revealed hyperperfusion of the thalamus and nucleus accumbens presenting in the symptomatic period, suggesting epilepsy-like neuronal discharge from these structures. Treatment for KLS has not been established, although lithium has been used in limited cases with insignificant efficacy. Here, we report a case of recurrent hypersomnia in which gabapentin was effective for the prevention of attacks. We speculate that the recurrent hypersomnia and behaviour disturbance are related to epilepsy-like neuronal discharge from the thalamus due to dysfunction in GABAnergic receptors.

Diagnostic pitfalls in children with sleep disorders: two cases with hypersomnia

Sleep disorders are common in children, yet several clinical pitfalls give rise to the unrecognition or improper management of those children. Here, we present diagnostic difficulties in two adolescents with narcolepsy and Kleine-Levin syndrome. The first patient was a 12-year-old girl who had been given Na-valproate for nearly a year because hypersomnia was initially perceived as unconsciousness periods of epileptic spells, and later attributed to the antiepileptic drug. The other patient was a 14-year-old boy who had been managed as a specific psychiatric disorder for several months despite the characteristic symptoms of Kleine-Levin syndrome (hypersomnia, hyperphagia, hypersexuality, behavioural and cognitive dysfunction). Both cases emphasize that sleep disorders could be manifested with various clinics and that there are several diagnostic challenges in children.

CONCLUSION

Sleep medicine needs to be given larger role in both training curriculum and post-graduate education for paediatricians.

Sarcoidosis: a rare cause of Kleine-Levine-Critchley syndrome

Hypothalamic sarcoidosis is a rare entity that can alter the hypothalamic-pituitary axis and induce various combinations of endocrine changes. We present a case of neurosarcoidosis with uncommon features of hypersomnolense and hyperphagia. Current strategies to increase awareness and prevention of the harmful effects of obesity require clinicians to be cognizant of potential disorders that produce these features The mechanism, differential diagnosis and therapeutic options of this organic etiology are reviewed.

Lower dopamine transporter density in an asymptomatic patient with Kleine-Levin syndrome

BACKGROUND

Kleine-Levin syndrome (KLS) is a rare disorder whose pathophysiological mechanisms remain unknown.

PATIENTS AND METHODS

To investigate dopamine abnormalities in KLS, a [99mTc]-TRODAT-1 single photon emission computerized tomography (SPECT) was performed in a patient with KLS during the asymptomatic period and compared with three matched healthy controls.

RESULTS

The patient had 14% lower striatal dopamine transporter binding potential (DAT-BP) compared to the mean DAT-BP of three healthy controls.

CONCLUSION

This study provides in vivo evidence for abnormalities in the DAT-BP, suggesting an involvement of the dopaminergic system in the pathophysiology of KLS.

Atypical Kleine–Levin syndrome: Can insomnia and anorexia be features too?

BACKGROUND

Kleine-Levin syndrome is an uncommon disorder with recurrent episodes of hypersomnia, clearly associated with behavioral abnormalities like binge eating, hypersexuality and abnormal behavior. Many patients may not necessarily fulfill minimum criteria described for diagnosis. We aim to report such patients with atypical presentation resembling the Kleine-Levin syndrome.

METHOD

We evaluated all patients at our clinic who had episodic disturbance in sleep and/or appetite lasting a few days to weeks, not necessarily fulfilling the International Classification of Sleep Disorders (ICSD) criteria for a diagnosis of Kleine-Levin syndrome, over 4 years. All clinical details, especially regarding sleep, appetite and behaviour during episodes, about prior and co-existing illnesses were noted. All patients were investigated with brain magnetic resonance imaging (MRI), electroencephalogram (EEG) and some with polysomnography.

RESULTS

Eighteen patients (5 females, 13 males) ranging in age from 12 to 55 years (median 18 years) were included in the study. The median duration of symptoms was 1.5 years, and the median number of episodes in each patient was six. The range of episode length was 18-300 h with a mean of 91.2h. Fourteen patients had a history of hypersomnia, 3 had only insomnia and 3 had both during their episodes, while 5 patients reported hyperphagia, 11 reduced appetite and 2 no change in appetite. Ictal EEG revealed evidence of sleep, while polysomnography showed reduced rapid eye movement (REM) latency and normal sleep architecture during the episode. MRI was normal in all patients, except one who showed non-specific abnormalities. All patients showed improvement with carbamazepine.

CONCLUSION

There are many patients with episodic alteration in sleep, appetite and behaviour with a course and treatment response similar to the classical Kleine-Levin syndrome, who otherwise do not fit the classical description for diagnosis of this condition.

Kleine-Levin syndrome: interface between neurology and psychiatry

We report the first episode of Kleine-Levin (KLS) syndrome in a 17-year-old male. The illness onset, clinical features, neuropsychological evaluation and polysomnographic recording are described. Typical symptoms hypersomnia, hyperphagia and sexual disinhibition were observed besides behavioral disturbances, polysomnographic and neuropsychological alterations. Behavioral disturbances similar to a manic episode including psychotic symptoms were relevant. The pharmacologic treatment included lithium, methylphenidate and risperidone. The introduction of risperidone aimed the control of psychotic symptoms and the persistent manifestations of hypersexuality after sleepiness control and to the best of our knowledge there are no other reports regarding risperidone use for KLS in the literature.

SPECT findings in the Kleine-Levin syndrome

STUDY OBJECTIVES

The Kleine-Levin Syndrome, is a rare disorder with onset during teenage years, but little is known on etiopathogenesis. Seven subjects with Kleine-Levin Syndrome accumulated over time had systematic SPECT studies during (n=5) and out (n=7) of the symptomatic period.

SUBJECTS

Seven boys with symptom onset between 11 and 17 years of age and at least 2 episodes per year were followed for a mean of 6 years.

METHODS

Electroencephalogram awake-asleep, computed tomography scan, and magnetic resonance imaging studies were performed before Tc-99m ECD single photon emission tomography (SPECT) obtained during day 4 or 5 (n=5) and at least 1 month away from the symptomatic period (n=7).

RESULTS

All imaging tests except SPECT were normal. Hypoperfusion of both thalami were seen during the symptomatic period that completely disappeared during the asymptomatic period. Hypoperfusion in other regions were also noted in some, but not all subjects. They persisted during the asymptomatic period in 2 cases over the temporal lobe (2/7 cases), frontal lobe (1/7 cases), and basal ganglia (1/7 cases). The largest amount of persistent hypoperfusion was seen in the subject with longest clinical evolution.

CONCLUSION

Hypoperfusion of the thalamus is a consistent finding during the symptomatic period, but perfusion abnormalities may persist even during the asymptomatic period. The longer the duration of the syndrome, the more extended the hypoperfusion regions during the asymptomatic period.

Kleine-Levin syndrome: a unique cause of fatigue in an athlete * Commentary

Kleine-Levin syndrome (KLS) is a rare disorder characterised, most notably, by periodic episodes of hypersomnolence and hyperphagia. Associated features of the disorder include a lack of concentration, mood changes, and anxiety. Laboratory tests may show slight changes in the electroencephalogram. However, clinical presentation and laboratory tests are normal during asymptomatic intervals. KLS most often presents in adolescent males, with complete recovery by the 3rd to 4th decade of life. Possible precipitating factors include excessive workload, febrile illness, and respiratory infections. Presented is a classical case of KLS in an adolescent male athlete. The patient's history, complete laboratory results, and symptoms are discussed. Possible treatments for this disorder are also mentioned, along with diagnostic criteria.

Kleine-Levin syndrome

Kleine-Levin Syndrome (KLS) is a rare disorder of uncertain etiology, characterized by recurring episodes of undue sleepiness lasting for days. We report a case of young female presenting with episodes of undue sleep along with hypersexuality and excessive food intake, who improved significantly on lithium and valproate. KLS should be considered in young patients, who present with episodes of undue somnolence.

The Kleine-Levin syndrome - effects of treatment with lithium -

Kleine-Levin syndrome (KLS) is a rare disorder which affects mainly adolescents. Periods of extreme somnolence alternate with megaphagia, psychomental changes and behavioural symptoms. The cause and pathogenesis of KLS remains unknown. Several treatments have been tried and recently lithium has been proposed for a prophylactic use in single cases. In view of the rarity of KLS, long-term results of lithium therapy have not been described yet. We report the clinical course of five adolescents with KLS who were treated with lithium. All patients showed significant EEG and polysomnographic changes during the episodes and had normal results in the interval. All patients had relapses while being treated with lithium. But episodes of hypersomnia under lithium therapy were shorter and monosymptomatic with lack of behavioural symptoms. Statistical modelling showed that the risk for a relapsing episode under maintenance of lithium drops per months of therapy from 100 % to 93 %, and furthermore that the maintenance of lithium shortens the mean duration of episodes to 19 %. No severe side effects were observed. In conclusion, in KLS with a high frequency of episodes and severe behavioural changes lithium may become a treatment option.

[Kleine-Levin syndrome: contribution of brain SPECT in diagnosis]

INTRODUCTION

Kleine Levin syndrome is an infrequent disorder of uncertain aetiopathogenesis that usually affects adolescent males, producing drowsiness and alterations in behaviour, appetite and sexuality. We report a clinically typical case in which the brain SPECT showed right frontal hypoperfusion.

CASE REPORT

Male aged 17, right handed, who presented drowsiness, apathy, alterations in his sexual behaviour (masturbations in public and attempted assault of women) and hyperphagia, which coincided with his undergoing an emotionally stressful period in his life. Brain SPECT revealed reduced flow in the right frontal lobe, although MRI and CSF study were normal. The polysomnographic study revealed a destructured pattern of sleep, with a reduction in phases III and IV and in REM sleep. He was treated with lithium and evolved favourably without any relapses during the 18 month follow up.

CONCLUSIONS

Cases of Kleine Levin syndrome with structural lesions have been reported, but most of them are idiopathic. A disorder in the hypothalamus and the limbic system is suggested. In our case, the findings from the brain SPECT confirmed a non dominant hypoperfusion of the frontal lobe, which could result from a phenomenon of diaschisis brought about by a diencephalic dysfunction.

[Sleep disorders and child and adolescent psychiatric illnesses]

As a symptom of many psychiatric disorders of childhood and adolescence, sleep disturbances often complicate the course and treatment of the underlying disorder. A somatic aetiology, e.g., as in Kleine-Levin syndrome or narcolepsy, may lead to diagnostic misinterpretations. It is not clear whether specific alterations of sleep architecture already exist in this age group and are thus trait markers for psychiatric disorders. Although it is well-known that sleep problems in adults, especially insomnia, are important in the later development of depressive syndromes, it is not clear whether persistent sleep problems during childhood constitute markers of vulnerability for psychiatric disorders. This review demonstrates interactions between sleep disturbances and psychiatric disorders of childhood and adolescence and their importance for assessment and therapy.

Clinical and polysomnographic characteristics of 34 patients with Kleine-Levin syndrome

There is only scant information on sleep characteristics and long-term follow-up in patients with Kleine-Levin syndrome (KLS). This study describes the clinical course, results of polysomnography and long-term follow-up in a relatively large group of patients with KLS. During the years 1982-97, we encountered 34 patients (26 males and eight females) with KLS. We were able to obtain the original polysomnographs from 28 males and four females. In 25 patients, data regarding their present state of health were obtained. Fourteen agreed to be present at a detailed interview and examination while 11 gave the information by phone. The mean age at onset was 15.8 +/- 2.8 years and the mean diagnostic delay, 3.8 +/- 4.2 years. The mean duration of a single hypersomnolent attack was 11.5 +/- 6.6 days. The main abnormal findings extracted out of 35 polysomnographs obtained from 32 patients during and/or in-between attacks included: decreased sleep efficiency, and frequent awakenings from sleep stage 2. All 25 patients reported present perfect health, with no evidence of behavioral or endocrine dysfunction. In adolescents with periodic hypersomnia, the diagnosis of KLS should be explored. Sleep recordings during a hypersomnolent period will often show frequent awakenings from sleep stage 2. The long-term prognosis is excellent.

Multiple sleep latency test and polysomnography in diagnosing Kleine-Levin syndrome and periodic hypersomnia

Kleine-Levin syndrome and periodic hypersomnia are often misdiagnosed initially because there is no objective test for these conditions. To determine the value of the Multiple Sleep Latency Test and polysomnography in this respect, the authors studied four patients with Kleine-Levin syndrome or periodic hypersomnia who had taken the Multiple Sleep Latency Test and undergone polysomnography during the symptomatic episode and/or during the asymptomatic interval. During but not between symptomatic episodes, the Multiple Sleep Latency Test revealed abnormal sleep latencies in all patients, and polysomnography revealed increased rapid eye movement propensity in one patient and a reduction in delta-sleep in two patients. In conclusion, the Multiple Sleep Latency Test and polysomnography are useful in diagnosing Kleine-Levin syndrome and periodic hypersomnia, especially when administered in a standardized fashion during and after the symptomatic period. The authors recommend that polysomnography and the Multiple Sleep Latency Test be performed no earlier than the second night after the onset of a symptomatic episode and the following day to reveal maximal hypersomnolence, and more than 2 weeks after a symptomatic episode to represent the asymptomatic interval.

[Klein-Levin syndrome: a neurological disease with psychiatric symptoms]

Kleine-Levin syndrome belongs to the recurrent hypersomnias group. It is a rare and benignant disease, occurring in young men 10 to 25 years old. The diagnosis is first clinical and the hypersomniac episodes, joined to psychiatric symptoms, are irregularly recurrent during few years. Diagnosis is uneasy during the first episode and in the attenuated forms... 500 cases have been described all around the world but it's highly likely that many patients haven't been listed. This syndrome, just like Gélineau disease, stands in the group of primary pathological hypersomnias. In a clinical point of view, the cardinal and constant symptom is hypersomnia. Psychiatric symptoms can be irregularly joined: megaphagia, sexual behavioural disorders, thymic disorders, personality modifications. The clinical examination is poor and aspecific. During an hypersomniac episode, a polygraphic recording during 24 or 48 hours will give diagnosis informations (fragmented and unstable sleep, reduction in stages 3 and 4 of non-REM sleep, reduction in REM sleep latency) and a biological and radiological evaluation will be necessary to exclude organic etiology (tumoral progres, infectious disease...). In a therapeutic point of view, prescription of psychostimulant drugs is recommended during fits and some treatments are used in a preventive way (lithium and carbamazepine).