Isaku Kurotori,1 Katsutoshi Shioda,1 Takaaki Abe,1 Rika Kato,1 Shizukiyo Ishikawa,2 Shiro Suda1 1Department of Psychiatry; 2Department of Medical Education Center, Jichi Medical University, Tochigi, JapanCorrespondence: Katsutoshi ShiodaDepartment of Psychiatry, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, JapanTel +81-285-58-7364Fax +81-285-44-6198Email kazs@jichi.ac.jpPurpose: To determine the clinical characteristics and course of severe avoidant/restrictive food intake disorder (ARFID) in hospitalized children and adolescents and compare them with those of patients with restricting-type anorexia nervosa (R-AN).Patients and methods: We conducted a retrospective chart review of inpatients diagnosed with ARFID or R-AN based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, at Jichi Children’s Medical Center Tochigi between April 1, 2007 and March 31, 2017. We compared the characteristics of the ARFID and R-AN patients at admission, during hospitalization, and after discharge.Results: Both the ARFID (n=13) and R-AN (n=79) patients required hospitalization for their medically unstable state. The features of ARFID group included concern about the aversive consequences of eating and avoidance of eating due to sensory concerns. Significant differences were found at admission between ARFID and R-AN groups in age (10.7 vs 12.7 years), family history of mental disorders (46.2% vs 17.7%), comorbid developmental disorders (6 vs 3 cases), and the time from onset to admission (3.9 vs 6.3 months). The body weight status, % ideal body weight (%IBW), % expected body weight (%EBW),