Effects of vitamin D on inflammatory responses and peripheral blood T lymphatic subsets in children with recurrent respiratory tract infection

Objective To investigate the effects of vitamin D on inflammatory response and T lymphocyte subsets in peripheral blood of children with recurrent respiratory infection. Methods The medical records of 106 children with recurrent respiratory infection from January 2017 to January 2018 were retrospectively analyzed. They were divided into two groups according to the treatment methods, with 53 cases in each group. The control group received routine anti-infective, anti-viral and symptomatic treatment. The observation group was treated with vitamin D on the basis of the control group. The inflammatory response, T lymphocyte subsets, symptom disappearance time and the recurrence frequency within 1 year were compared between the two groups. Results After 3 months of treatment, cluster of differertiation(CD) 3+, CD4+, CD4+ /CD8+ in both groups were increased, while C-reactive protein(CRP), tumor necrosis factor-α(TNF-α), interleukin-6(IL-6) and interleukin-1 (IL-1)levels in both groups were decreased. The change in the observation group was larger than that in the control group (t=6.848, 8.956, 10.636, 20.046, 11.926, 10.174, 7.804, P all=0.000). The duration of symptom disappearance in the observation group was shorter than that in the control group, and the frequency of recurrence within 1 year was less than that in the control group, with statistically significant difference (t=21.853、9.975, 10.921, 14.203, 22.529, P all =0.000). Conclusions The application of vitamin D in the treatment of children with recurrent respiratory tract infection can effectively reduce the inflammatory reaction of the body, improve the peripheral blood T lymphocyte subsets, and promote the improvement of clinical symptoms. Key words: Repeated respiratory tract infection; Vitamin D; Tlymphatic subsets; Inflammatory response