Obsessive compulsive disorder (OCD) in childhood was first described by Legrand du Saulle in late XIX century, however, a systematic study in pediatric population was not made until 1986, by Rapoport. It is has been documented in scientific literature that younger patients usually hide their symptoms because of shame or that they do not find their obsessions and compulsions excessive, so that they feel them in an egosyntonic way, delaying diagnosis until several years after their first symptoms.

To highlight the specific symptoms in Pediatric OCD and review its treatment and approach through the study of a case report.

A 11-year-old boy was referred by his paediatrician to a child mental outpatient service for behavioural disturbances in the last few months. For the last three years, he had been performing rituals of cleaning, order and checking, increasingly complex and with a significant impact on his life, to the point of not being able to go to school and have other members of his family involved. He also had religious and catastrophic obsessions that generated him important distress. He was treated with high doses of sertraline and low doses of risperidone, and cognitive-behavioral psychotherapy with exposure response prevention and training in relaxation techniques were associated to the treatment. The patient improved partially.

This case illustrates the delay in the diagnosis of Pediatric OCD itself as well as the complexity when treating this disorder.