Kleine-Levin syndrome: clues to aetiology.

Kleine-Levin syndrome (KLS) is the commonest recurrent sleep disorder, with a prevalence of 1-2 per million population. Clear diagnostic criteria are now defined, but effective treatment remains elusive. The significant body of published literature allows consideration of possible aetiological mechanisms, an understanding of which could guide the development of therapeutic strategies. Functional imaging studies have been inconclusive; although diencephalic abnormalities are a common finding, no consistent pattern has emerged, and these studies have not revealed the mechanism(s) underlying the development of the abnormalities detected. An autoimmune aetiology is consistent with the available data. In this review, we argue that, in order to further our understanding of KLS, there needs to be a co-ordinated international effort to standardise approaches to functional imaging studies, genetic analyses that specifically address the possibility of an autoimmune aetiology, and clinical trials of immunosuppressive therapies.

Klein-Levin syndrome versus bipolar disorder not otherwise specified- diagnostic challenges.

Hypersomnia presents as excessive daytime sleepiness with a prevalence of 7.1% in general population. Hypersomnia has serious negative effects on persons functioning. The aetiology of hypersomnia can be due to neurological conditions, primary sleep disorders, Substance induced, Psychiatric disorders and idiopathic. Klein-Levin syndrome (KLS) is condition characterised by hypersomnia, hyperphagia and hypersexuality. Among the psychiatric disorders, hypersomnia is seen in bipolar depression. In bipolar disorder, hypersomnia can be present during the depressive episode and also inter-episodically. Here is a case report on hypersomnia and diagnostic challenges.

The "Known Unknowns" of Kleine-Levin Syndrome: A Review and Future Prospects.

Kleine-Levin syndrome (KLS) is a rare, homogeneous, debilitating sleep disorder characterized by episodic hypersomnia, cognitive impairment, and behavioral changes. The etiology, pathophysiology, and optimal management of KLS remain uncertain. We identify the 5 key areas requiring urgent attention: KLS immunopathogenesis studies, next-generation genetics, multimodal functional imaging, biomarker discovery, and clinical drug trials. A centralized registry of afflicted individuals must be established. Disease uniformity should make the identification of associated genetic or imaging biomarkers easier, but clinical efforts require laboratory-based research to model the disease and generate preclinical data for clinical translation.

Kleine-Levin syndrome elicited by encephalopathy with reversible splenial lesion.

Kleine-Levin syndrome is a rare sleep disorder of unknown etiology characterized by repetitive episodes of hypersomnia between asymptomatic periods. We report the case of a 13-year-old girl who presented with drowsiness triggered by influenza A as the first episode. Magnetic resonance imaging (MRI) on day 6 showed transient reduction of diffusion in the corpus callosum splenium. The patient was diagnosed with encephalopathy with a reversible splenial lesion. The symptoms resolved after 10 days, but additional episodes of hypersomnia lasting 5-10 days occurred 1, 5, 6, 11, 13, and 25 months after the first episode. MRI during hypersomnia indicated no lesions, and sleep duration and cognition were normal between episodes. The patient was diagnosed with Kleine-Levin syndrome. Electroencephalographic and clinical findings during the first episode were similar to those during the other episodes. Encephalopathy with a splenial lesion and Kleine-Levin syndrome may have similar pathological mechanisms causing a disturbance in consciousness.

Migraine with brainstem aura presenting as recurrent hypersomnia (Kleine-Levin syndrome).

Recurrent hypersomnia, or Kleine-Levin syndrome, is rare and frequently causes substantial diagnostic anxiety and delay. Patients often undergo multiple investigations to rule out other causes of encephalopathy. The treatment options are unsatisfactory. Migraine with brainstem aura has not previously been widely considered in the medical literature as a differential diagnosis. We describe two patients referred to a tertiary sleep neurology service with a putative diagnosis of Kleine-Levin syndrome. Each described attacks of hypersomnia with elements of migraine with brainstem aura, in addition to having a history of migraine with aura. Simple acute migraine treatment clearly attenuated further attacks. These cases generate discussion as to the common features and potential mechanisms underlying both disorders. Furthermore, they highlight a hitherto underexplored alternative diagnosis of Kleine-Levin syndrome. This provides scope for offering established and effective migraine treatment options to patients who with a potential misdiagnosis of Kleine-Levin syndrome, providing scope for offering established and effective migraine treatment to some patients originally diagnosed with a rare condition for which there is no current consistently effective therapeutic options.

An unusual occurrence of Kleine-Levin syndrome in a man with refractory immune thrombocytopenic purpura: a case report.

INTRODUCTION: Kleine-Levin syndrome is an extremely rare neurological entity characterized by recurrent episodes of hypersomnia which are sometimes associated with compulsive hyperphagia and behavioral changes. Autoimmunity has recently been proposed as a factor contributing to its pathogenesis. Immune thrombocytopenic purpura is a relatively common autoimmune disease showing a lot of complexity and uncertainty regarding its treatment regimens and its refractory nature in some cases. CASE PRESENTATION: A 32-year-old Persian White man visited his private hematologist complaining of recent episodes of epistaxis and appearance of petechial lesions 24 hours after receiving a meningococcal vaccine. He had a history of immune thrombocytopenic purpura 13 years before his presentation. Based on his history and laboratory findings, his condition was diagnosed as a relapse of immune thrombocytopenic purpura and was managed accordingly. He did not respond to first-line corticosteroid regimens and later developed neurological symptoms as recurrent episodes of hypersomnia and hyperphagia. After a complete clinical and paraclinical evaluation and ruling out other possible conditions, he was given a diagnosis of Kleine-Levin syndrome. He was followed up for his immune thrombocytopenic purpura and received different treatment regimens none of which were adequately successful except intravenous immunoglobulin that was only temporarily effective. He has had 4 documented self-limited episodes of Kleine-Levin syndrome since his initial presentation. CONCLUSIONS: Immune thrombocytopenic purpura may be associated with meningococcal vaccination in adulthood. Responses to treatment in immune thrombocytopenic purpura vary among patients. Our patient only had a transient acceptable response to intravenous immunoglobulin while all other options failed to improve his platelet count. Concurrence of immune thrombocytopenic purpura and Kleine-Levin syndrome supports the role of autoimmunity as the proposed pathophysiological mechanism of Kleine-Levin syndrome.

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.

A case of PANDAS with Kleine-Levin type periodic hypersomnia.

We report on an 11-year-old girl, presenting with clinical features suggesting both pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) and Kleine-Levin syndrome (KLS), who was successfully treated with penicillin prophylaxis. KLS is a sleep disorder characterized by recurrent episodes of hypersomnia and at least one of the following symptoms: (1) cognitive or mood disturbances, (2) megaphagia with compulsive eating; (3) hypersexuality with inappropriate behaviors; and (4) abnormal behavior. The etiopathogenesis is still unclear and there is no effective treatment other than symptomatic therapies. This intriguing case report suggests novel insight into the pathogenesis of this rare and enigmatic syndrome.

Relationship between Kleine-Levin syndrome and upper respiratory infection in Taiwan.

STUDY OBJECTIVES: In Kleine-Levin Syndrome (KLS), new episodes of hypersomnia are often preceded by an acute flu-like syndrome or upper airway infection 3 to 5 days before onset. This study investigated the relationship between the occurrence of mild upper respiratory tract infections (URIs) in the general population and the occurrence and seasonality and hypersomnic episodes in KLS patients. DESIGN: This investigation was a longitudinal clinical study. Based on data obtained from the National Health Research Institutes between 2006 and 2007, the timing of hypersomnic episodes in 30 KLS patients were compared with calendar reports of URI events, and the results compared with age-matched general Taiwanese population. MEASUREMENTS: Clinical symptoms, physical examination, polysomnographic recording, SPECT study, and laboratory tests affirming KLS during both periods of hypersomnic attack and non-attack were collected. Every symptomatic episode was then followed up. The cross-correlation function (CCF) and bivariate correlations analysis were performed to see the relationship between KLS and URIs. RESULTS: A positive finding of CCF analysis and significant bivariate correlations were found between KLS episodes and URI in the general population (r = 0.456*). In onset of hypersomnia, significant correlations existed among "acute upper respiratory infections" (r = 0.446*), "acute bronchitis and bronchiolitis" (r = 0.462*), and "pharyngitis and nasopharyngitis" (r = 0.548*) subtypes of infections. A positive correlation between higher reports of symptomatic hypersomnia and URI also existed in a given season. A positive nonsignificant trend for "allergic rhinitis" (r = 0.400) was also found. CONCLUSION: The agent behind URI or its consequence (such as fever) is associated with increased incidence of KLS episodes and may explain periodic symptomatic recurrences.

Primary hypersomnias of central origin.

Hypersomnia is a frequently encountered symptom in clinical practice. The cardinal manifestation is inappropriate daytime sleepiness, common to all types of hypersomnias. Hypersomnias of central origin are a rare cause of excessive daytime sleepiness, much rarer than the hypersomnia related to other pathologies, such as sleep-disordered breathing. Narcolepsy, with or without cataplexy, remains the most well studied of the primary hypersomnias. Although recognized more than a century ago, it was not until the end of the 20th century that major breakthroughs led to a better understanding of the disease, with hope of more specific therapies. The authors review the major aspects of this disorder, including the newer treatment modalities. Idiopathic hypersomnia is also part of the primary hypersomnias. Although difficult to diagnose, certain peculiarities stand out to help us differentiate it from the more commonly seen narcolepsy. The recurrent hypersomnias, particularly the Kleine-Levin syndrome, will be discussed. This rare disorder has been studied more closely in the last few years with abundant epidemiologic data assembled through literature and worldwide case reviews. Understanding the primary central hypersomnias warrants a thorough look from the original description, as well as a peek at the future, while more efficacious diagnostic and therapeutic interventions are currently being developed.

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.

Kleine-Levin syndrome: history and brief review.

Episodic hypersomnia, compulsive excessive eating and erotic behaviour, with schizophrenic-like mental symptoms are the hallmarks of the rare Kleine-Levin syndrome. This paper traces the origins of its description back to the 18th century and the changing concepts of its complex organic-psychogenic aetiology. The eventual, spontaneous disappearance of the syndrome is unexplained.

Episodic hypersomnia and unusual behaviors in a 14-year old adolescent.

CASE: John, a 14-year old white male of European Jewish descent without a prior history of medical or psychiatric problems, presented following several days of increased need for sleep (16-20 hours per day), disorientation, difficulty maintaining attention and concentration, bizarre behaviors. He was sexually inappropriate toward his mother, sister, and housekeeper, masturbated in public, and sang nonsense lyrics. In addition, he had brief periods of agitation, paranoia (including fear that he was being followed and that he would be hurt by the physicians), and periods of distraction by auditory and visual hallucinations. His appetite increased significantly during this time. One week prior to the onset of these symptoms, he traveled to the Midwest where he experienced several days of nausea, vomiting, and diarrhea.John's physical and neurological examinations were normal except for the behaviors noted above. A medical evaluation revealed a normal brain computerized tomogram (CT) and magnetic resonance imaging (MRI). Urine toxicology screen, a comprehensive metabolic blood panel, and a complete blood count were normal. A lumbar puncture demonstrated a slightly elevated opening pressure (24 centimeters); the cerebrospinal fluid examination was unremarkable for cells, protein and glucose. Following the lumbar puncture, for which he had received midazolam, he had a brief, 30-45 minute episode of lucidity in which he was able to describe feeling like he was "in a fog."John was transferred to a psychiatric hospital where he recovered over several days and was discharged home. After three weeks of complete recovery, he acutely developed profound fatigue and the previously seen bizarre behaviors returned and persisted for 2 weeks. Following a 2-week period without symptoms, a similar behavior pattern recurred for the third time. The third episode differed from the first two in that he initially developed mental status changes and then developed symptoms of hypersomnolence. John has now been completely recovered from the third two week episode for one week and is taking summer school classes and enjoying socializing with his friends.

Kleine-Levin syndrome: a systematic review of 186 cases in the literature.

Kleine-Levin syndrome (KLS) is a rare disorder with symptoms that include periodic hypersomnia, cognitive and behavioural disturbances. Large series of patients are lacking. In order to report on various KLS symptoms, identify risk factors and analyse treatment response, we performed a systematic review of 195 articles, written in English and non-English languages, which are available on Medline dating from 1962 to 2004. Doubtful or duplicate cases, case series without individual details and reviews (n = 56 articles) were excluded. In addition, the details of 186 patients from 139 articles were compiled. Primary KLS cases (n = 168) were found mostly in men (68%) and occurred sporadically worldwide. The median age of onset was 15 years (range 4-82 years, 81% during the second decade) and the syndrome lasted 8 years, with seven episodes of 10 days, recurring every 3.5 months (median values) with the disease lasting longer in women and in patients with less frequent episodes during the first year. It was precipitated most frequently by infections (38.2%), head trauma (9%), or alcohol consumption (5.4%). Common symptoms were hypersomnia (100%), cognitive changes (96%, including a specific feeling of derealization), eating disturbances (80%), hypersexuality (43%), compulsions (29%), and depressed mood (48%). In 75 treated patients (213 trials), somnolence decreased using stimulants (mainly amphetamines) in 40% of cases, while neuroleptics and antidepressants were of poor benefit. Only lithium (but not carbamazepine or other antiepileptics) had a higher reported response rate (41%) for stopping relapses when compared to medical abstention (19%). Secondary KLS (n = 18) patients were older and had more frequent and longer episodes, but had clinical symptoms and treatment responses similar to primary cases. In conclusion, KLS is a unique disease which may be more severe in female and secondary cases.

Kleine-Levin syndrome and encephalitis.

Kleine-Levin Syndrome is characterized by hypersomnolence, hyperphagia and sexual disinhibition. The article reported a case of 10-year-old boy with a two-week history of altered sensorium, irrelevant talks, markedly increasing appetite and tendency to sleep most of the times. Immediately preceding to it the child had been an episode of enteric fever confirmed by the serological tests.