[Obesity--hypoventilation syndrome: sometimes a difficult diagnosis]

Described in the specialty literature for over one century under the name of Pickwick syndrome, the obesity--hypoventilation syndrome (OHS) includes the triad: obesity--hypoventilation--hypersomnia. In Romania, this entity is rarely recognized and, despite the developments in specific investigations, the disease is frequently difficult to differentiate from other respiratory disorders during sleep. The authors try to clarify some issues related to pathophysiologic mechanism and contribution of mechanical factors or of respiratory nervous center etc. References are made about the leptin involvement. Clinical appearance and therapy modalities are added to the description of the disease.