Impact of compliance with cholecalciferol administration on the incidence of respiratory infections in young children

Introduction. Data on the vitamin D receptors (VDR) found on the surface of a large number of cell types of the human body were first published several decades ago, which served as a prerequisite to study the role of vitamin D in the development of some diseases, including infections.Objective of the study.Evaluate the relationship between administration of cholecalciferol supplements, the synthesis of defensins, and the incidence and morbidity patterns of acute respiratory infections (ARI) in young children.Material and methods.108 healthy children aged 1 month to 3 years were examined, of which 34 (31.5%) were vitamin D sufficient, 40 (37.0%) had a vitamin D insufficiency, 27 (25.0%) had a vitamin D deficiency and 7 (6.5%) children had severe vitamin D deficiency. After the course of treatment of vitamin D deficiency with therapeutic doses, all patients were prescribed prophylactic doses of cholecalciferol supplements (1000 IU/day) for a 6-month course.Results. Therapeutic doses of cholecalciferol promoted β1 and β2-defensin expression; a direct correlation was found between the daily dose of vitamin D and the increase of β2-defensin expression (r = 0.34, p