Kleine–Levin syndrome: Etiology, diagnosis, and treatment

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 hypersexuality. Each episode is of brief duration varying from a week to 1–2 months and affected people are entirely asymptomatic between episodes. No definite cause has been identified, and no effective treatments are available even though illness is having well-defined clinical features. Multiple relapses occur every few weeks or months, and the condition may last for a decade or more before spontaneous resolution. In this study, PubMed was searched and appropriate articles were reviewed to highlight etiology, clinical features, and management of KLS. On the basis of this knowledge, practical information is offered to help clinicians about how to investigate a case of KLS, and what are the possible treatment modalities available currently for the treatment during an episode and interepisodic period for prophylaxis. Comprehensive research into the etiology, pathophysiology, investigation, and treatments are required to aid the development of disease-specific targeted therapies.