[A hidden compulsion].

Obsessive-compulsive disorder (OCD) is a frequent psychiatric disorder. Patients do not always present with obsessions or compulsions and this may complicate the process of diagnosing and starting adequate treatment. In this article three patients suffering from OCD but not presenting with obsessions or compulsions are discussed. In the first case, in a 42-year-old woman, the presenting symptom is a therapy-resistant dermatitis, due to excessive washing. The second patient, a 27-year-old man, presented with a depression, a frequent comorbid condition. In the third case, a 34-year-old man, the effects on and the suffering of the partner and family of a patient with OCD (they were asked to co-operate in his compulsive behaviour) were the reason for his wife to consult the general practitioner. OCD has a lifetime prevalence rate of 2.5% and is somewhat more frequent in females than in males. The most characteristic symptoms are obsessions and/or compulsions. They cause marked distress, are time consuming (take more than 1 hour a day), and interfere significantly with the person's functioning (occupational, social activities, relationships). Neurobiological studies suggest genetic influences and dysfunctional neuronal circuits in the brain. The treatment of OCD consists of pharmacotherapy and behavioural therapy, but it is a lifelong condition.