Hikikomori, a form of severe social isolation, once characterized as a Japanese cultural-bond behavior with social and economic consequences, it is now being described in other countries. Its presentation mimics some clinical features of various classified mental diseases, such as prodromal phase of schizophrenia, personality disorders, Internet dependence, social phobia or depression, without fulfilling their defining criteria.

This work aimed to do a brief review of this subject, describing one case that is probably the first ever reported in Portugal, comparing it with similar cases around the world.

The patient was a 22-year-old male, taken to psychiatry evaluation after 4 years of social withdrawal, avoiding or blocking any contact even with family members, which resulted in work and school impairment. He spent most of his days locked at his room, investing his time in particular interests and Internet use, only leaving to eat or do his basic hygiene. At that time, he presented no affective or psychotic symptoms and perceived his behavior as egosintonic. After six appointments with psychotherapeutic approach, he was able to get a job and improved his communication with the others, especially with family.

This case fits most of the reports found on literature, in its presentation and clinical management. Hikikomori is not considered yet a disorder and further documentation of these cases is still needed to define its place in psychiatric nosology.

The authors have not supplied their declaration of competing interest.