Dai Miyawaki, Ayako Goto, Yoshihiro Iwakura, Kaoru Hirai, Yusuke Miki, Naomi Asada, Hiroki Terakawa, Koki Inoue

Early-onset obsessive-compulsive disorder (OCD) is more severe than later-onset OCD. There are no reports of any early-onset OCD patients being cured, especially with respect to preschoolers. In this case report, we describe the successful treatment and cure of a 6-year-old preschool girl with severe OCD since the age of 3. At the age of 3, the patient began to fear contamination and danger to herself and her family, leading to excessive hand-washing, and several months later, ritualized checking. The OCD symptoms waxed and waned for about 3 years and thereafter worsened gradually over a few weeks, culminating in a refusal to eat and dress. At the age of 6, after a week of inpatient pediatric treatment with no improvement, the patient was transferred to Osaka City University Hospital to seek psychiatric treatment. The patient fully recovered from OCD following family-based cognitive-behavioral therapy (CBT) and short-term use of low-dose fluvoxamine in an inpatient setting. After treatment, the OCD symptoms disappeared with complete remission for over 3 years. Now, aged 9, the patient has good global functioning and is well adjusted in her daily life with no need for any treatment. To the best of our knowledge, this is the first report of preschool-onset OCD with long-term complete remission with inpatient treatment in a preschooler with severe OCD. Some preschoolers with very early-onset OCD may have good prognosis without continuous pharmacotherapy, although the symptoms with the onset are severe enough to require hospitalization. Preschool-onset OCD is likely to be misdiagnosed as separation anxiety disorder. Our findings suggest that family-based CBT, which is the treatment of choice for preschool-onset OCD, can be applicable to inpatient treatment. Early detection and intensive intervention of OCD in preschoolers may improve the chance of remission.