Abstract
Hikikomori, or severe social withdrawal, in Japan's young people has been a prominent public mental health concern since around 2000. A case of skin necrosis in a hikikomori teenager is reported in this article. From the patient's history and the shape of the skin ulcer, we diagnosed her necrotic ulcer was pressure sore, caused by sitting on the toilet seat for a long time. Antibiotic treatment, surgical debridement and skin were performed. The ulcer was healed eight weeks after admission. In future, the incidence that medical staff, not psychiatrists, encounters in hikikomori patients may increase because of the increase of the secondary disease based on hikikomori. The consensus about the causes, diagnosis and therapeutic interventions for hikikomori will be required not only by psychiatrists but also by all of the medical staff now, with urgency.