Clinical Characteristics and Outcomes of Pediatric Vitamin C Deficiency

<b>Background:</b> Vitamin C deficiency remains an under-recognized condition in children, especially in Southeast Asia. This study aimed to study the clinical characteristics, dietary risk factors, and outcomes of pediatric vitamin C deficiency in a tertiary hospital in Southern Thailand. <b>Methods:</b> This retrospective study reviewed the medical records of children aged 1 to 15 years diagnosed with vitamin C deficiency from 2004 to 2024. Diagnosis was based on serum ascorbic acid levels below 0.4 mg/dL, or clinical-radiographic findings. Data collected included demographics, developmental status, dietary history, clinical presentations, radiological and laboratory results, treatment, and outcomes. <b>Results:</b> Forty-six children were diagnosed; the median age was 4.8 years, and 60% were male; developmental delay was present in 54.4%. The majority had poor dietary intake, with 73% not consuming adequate fruits and vegetables; no significant differences were observed when classified by developmental status. Common clinical signs included: limb pain (76.1%), refusal to walk (52.2%), and bleeding gums (39.1%). Radiographs showed osteopenia in 73.8% and white line of Frankel in 47.6%. Serum ascorbic acid deficiency was significantly associated with low fruit and vegetable intake and excessive milk consumption over the recommendations (<i>p</i> < 0.05). Treatment with oral vitamin C resulted in clinical improvement; although, residual symptoms persisted in some cases. <b>Conclusions:</b> As pediatric vitamin C deficiency is still of concern, this study highlights the importance of early detection in at-risk children and the critical role of detailed dietary history to identify inadequate nutrition. Prompt recognition and intervention can prevent misdiagnosis and improve clinical outcomes. Hence, strengthening parental education on nutritional intake is essential to reduce future incidences.