Retrospective cross-sectional analysis of Vitamin D deficiency in pediatric patients: Clinical findings from a tertiary care centerpediatric center

Objective: The 25-Hydroxyvitamin D (25(OH)D) deficiency is a prevalent global health concern, particularly among children, leading to conditions such as rickets and increasing the risk of respiratory infections and chronic diseases. Contributing factors include limited sun exposure, poor dietary intake, and growth demands. This study aimed to assess the clinical and laboratory characteristics of pediatric paients with 25-Hydroxyvitamin D (25(OH)D) deficiency at our clinic. Material and Methods: This retrospective study was conducted at a tertiary care center in İstanbul, Türkiye, including pediatric patients diagnosed with 25-Hydroxyvitamin D (25(OH)D) deficiency between January 2020 and December 2023. Data on sociodemographic, medical history, symptoms, physical examinations, and laboratory results were extracted from electronic medical records. Patients with 25-Hydroxyvitamin D levels below 20 ng/mL were classified as deficient. Correlation analyses were employed to assess the associations between 25-Hydroxyvitamin D (25(OH)D) levels and clinical factors. The study was approved by the Istanbul Medipol University Ethical Review Board. Results: A total of 5229 pediatric patients with 25-Hydroxyvitamin D (25(OH)D) deficiency or insufficiency were included in the study, with a slight female predominance (51%). The highest frequency of deficiency was observed among children aged 2 to 3 years. Symptom-onset complaint records were retrospectively reviewed. The most commonly documented complaints at presentation were fatigue (30.75%), followed by non-specific or asymptomatic presentations (28.95%). Given the retrospective design of the study, these symptoms may not be specific to 25-Hydroxyvitamin D (25(OH)D) deficiency and could be attributable to other concurrent conditions. Notably, in several cases, 25-Hydroxyvitamin D (25(OH)D) deficiency was detected incidentally during medical evaluations performed for unrelated reasons. Conclusion: 25-Hydroxyvitamin D (25(OH)D) deficiency is a common condition in childhood and may present with a wide range of symptoms or remain asymptomatic. Early detection is crucial, particularly in at-risk groups such as toddlers and children with limited sun exposure. Clinicians should be aware of the non-specific nature of symptoms and consider 25-Hydroxyvitamin D (25(OH)D) status in routine pediatric evaluations. Broader awareness and preventive strategies are needed to reduce the clinical burden of this silent but prevalent deficiency.