Clinical Features of Hypo- and Hypervitaminosis of Fat-Soluble Vitamins in Pediatric Patients

: Fat-soluble vitamins (A, D, E, and K) are crucial for pediatric health, contributing to normal cellular function, growth, immune defense, and development. Unlike water-soluble vitamins, they are absorbed with dietary fats and stored in the liver and adipose tissue, leading to risks of deficiency (hypovitaminosis) and toxicity (hypervitaminosis) in certain physiological and pathological conditions. This narrative review aimed to summarize the clinical manifestations, diagnostic considerations, and management of hypo- and hypervitaminosis of fat-soluble vitamins in pediatric populations. A comprehensive literature review was conducted, highlighting the physiological roles, symptoms of deficiency and toxicity, diagnostic strategies, and treatment options, with particular focus on high-risk groups, including neonates and children with malabsorption or dietary restrictions. Pediatric patients are especially vulnerable to vitamin imbalances due to rapid growth and specific developmental needs. Deficiencies can result in vision problems, bone disorders, immune dysfunction, and coagulation issues, while excess intake can lead to toxicity. Management strategies include clinical assessment, biochemical testing, supplementation, dietary counseling, and public health interventions. Early detection and preventive measures are essential. Future research is needed to explore non-classical roles of these vitamins and optimize supplementation guidelines.