Research progress on the role of vitamin D in respiratory tract infection in children / 中华实用儿科临床杂志

ABSTRACT

In recent years,vitamin D research has made important progress in non-skeletal health. Lack of vi-tamin D or deficiency can lead to the susceptibility of children with respiratory tract infection (RTI). RTIs are more likely to occur with serum 25 hydroxyl D [25(OH)D]concentrations < 38 μg/ L (95 nmol/ L). Daily or weekly vita-min D supplementation has a protective effect on RTI. Vitamin D has a major impact on the immune system and directly or indirectly regulates more than 200 different genes by binding 1,25 dihydroxy D[1,25 (OH) 2 D]to the vitamin D re-ceptor (VDR). Regulation of innate immunity causes downstream reactions to produce antimicrobial peptides,which lead to the killing of various pathogenic bacteria. In addition,regulation of adaptive immunity [helper T lymphocyte (Th)1,Th2,regulatory T cells(Treg)cells and Th17]and regulation of the inflammatory cascade by regulating the nu-clear factor kappa B (NF-κB)pathway. These are good for prevention and treatment of children RTI. The recommen-ded daily dose of vitamin D supplementation recommended by the American Medical Institute for bone health and the optimal 25(OH)D concentration for preventing and treating vitamin D supplementation in other non-bony iliac system diseases are also described. This article aims to further understand vitamin D and introduce its research progress in the prevention and treatment RTI in children.