A nationwide multicenter observational study on childhood scurvy in Japan.

OBJECTIVES: Although scurvy is rare in developed countries, cases in children with selective diets due to neurodevelopmental disorders have been increasingly reported in Japan. In this nationwide multicenter observational study, we aimed to clarify the clinical characteristics and diagnostic challenges faced by children with scurvy in Japan. METHODS: We conducted a two-step nationwide multicenter observational study. An initial screening survey was sent to 407 training hospitals certified by the Japan Pediatric Society to identify institutions that had encountered children with scurvy between 2014 and 2023. A second, detailed questionnaire was sent to institutions that had managed children with scurvy, as well as those identified through a literature search, to collect data on clinical features, diagnostic processes, treatments, and outcomes. RESULTS: Forty-seven children with scurvy, from 35 hospitals were included in the final analysis. The median age was 3.6 years, 70% were male, and only 36% had a body mass index standard deviation score below -2.0. A selective diet was observed in 96% of patients; 72% had autism spectrum disorder (ASD), and 13% had no underlying disease. The most common presenting symptom was gait disturbance (88%), whereas weight loss was observed in only 21% of patients. Additionally, 30% were misdiagnosed, and 38% underwent potentially harmful examinations. Pretreatment serum ascorbic acid levels were below the detection limit in 77%. CONCLUSIONS: In Japan, scurvy in children was predominantly associated with a selective diet, particularly among those with ASD. Careful dietary assessment is important to avoid diagnostic delay and irreversible complications.