The Kleine-Levin syndrome

Abstract

As so often in uncommon syndromes difficulties in diagnosis are a problem, especially when symptoms are strange and suggest a psychiatric disorder. Such an example is the Kleine-Levin syndrome. It occurs mainly during adolescence, and may last for a number of years, but the prognosis for most patients is excellent. The symptoms are described, especially the triad of episodes of hypersomnia, compulsive food intake and abnormal behavior; and also the signs of autonomic dysfunction. The unusual symptoms can lead to social withdrawal and inter-episodic morbidity. In addition there may be evidence of long-term effects such as impaired recent memory. Investigations are likely to be negative, except for the electroencephalogram, which can be abnormal; especially during sleep. The differential diagnosis is discussed, particularly from other sleep disorders, and from psychiatric conditions. The definite cause of the syndrome is not known, but a disturbance of diencephalic function can explain the symptoms, and they have been recorded after injury to this part of the brain. There may well be a primary disturbance in the balance of neurotransmitters. Treatment with a variety of drugs has been tried, and the response to lithium has been the most encouraging.