Background: vitamin D influences the immune system and the inflammatory response. It is known that vitamin D supplementation reduces the risk of acute respiratory tract infection. In the last two years, many researchers have investigated vitamin D's role in the pathophysiology of COVID-19 disease.
Results: the findings obtained from clinical trials and systematic reviews highlight that most patients with COVID-19 have decreased vitamin D levels and low levels of vitamin D increase the risk of severe disease. This evidence seems to be also confirmed in the pediatric population.
Conclusions: further studies (systematic review and meta-analysis) conducted on children are needed to confirm that vitamin D affects COVID-19 outcomes and to determine the effectiveness of supplementation and the appropriate dose, duration and mode of administration.
Keywords: , IFN-γ, reduce interferon-gamma; , RAS, renin-angiotensin system; ACE2, angiotensin-converting enzyme 2; CI, confidence interval; COVID-19; Children; DAMPs, damage-associated molecular patterns; DCs, dendritic cells; HR, Hazard Risk; ICU, intensive care unit; IL, interleukin; IgE, immunoglobulin E; Immunity; MD, mean difference; NK, natural killer; OR, odds ratio; PAMPs, pathogen-associated molecular patterns; PRRs, pattern recognition receptors; RCTs, randomized control trials; RR, risk ratio; SARS-CoV-2 infection; TLRs, Toll-like receptors; TNF-α, tumor necrosis factor-α; Treg cells, CD, regulatory T cellcluster of differentiation; VDRs, vitamin D receptors; Vitamin D.
© 2022 Published by Elsevier B.V.