Журнал «Боль. Суставы. Позвоночник» 2 (18) 2015

Статья опубликована на с. 85-86

Introduction. Last years much attention is paid to studying the role of vitamin D in the formation of extraosseous pathology. Epidemiological studies were conducted to show a relationship between vitamin D deficiency and a higher level of respiratory infections [1–3]. At the same time the influence of vitamin D sufficiency in the development of acute respiratory infections in children has been less studied [2].

Therefore, the aim of our study was to explore the role of vitamin D in the formation of recurrent flow of respiratory infections in young children.

Materials and methods. There were 52 children in the study group (26 girls and 26 boys) aged from 13 to 36 months, the frequency of respiratory infections was 6 and more times a year; control group consisted of 50 children (of similar age and sex) with a frequency of episodes of respiratory diseases 5 a year or less. All the children were given standard prophylactic dose of vitamin D, the symptoms of rickets were absent.

The level of vitamin D provision was assessed by determining the 25(OH)D₃ by immune chemiluminescent method using the apparatus Elecsys 2010 Roche. The study of immune parameters was carried out by direct rosette method of erythrocytes coated with monoclonal antibodies. Descriptive statistics are given as median and interquartile range. Comparison of parameters was performed by Mann–Whitney test (U–Test). To understand the nature and the coupling between the studied parameters we used Spearman rank correlation coefficient.

Results. There was an essential, statistically significant (U = 24.00, Z = 3.09, p = 0.002) difference between the level of 25(OH)D in children with the recurrent respiratory infections (32,70 [23,03–39,81] ng/ml) and in occasionally ill children (46,36 [40,21–52,51] ng/ml).

Among children who were predisposed to recurrent respiratory disease course, children with subclinical deficiency of vitamin D dominated — 50 %, 6 % had an extreme shortage of vitamin D, and in 44 % of cases the level of vitamin D was sufficient. In the control group — twice as many children have an adequate vitamin D level (88 %), 12 % had subclinical vitamin D deficiency (according to a scale of Cianferotti and Marcocci (2012) [1]. Analysis of the level of vitamin D in children predisposed to recurrent respiratory disease course according to the months of the year found that 25(OH)D₃ did not reach sufficient levels (above 30 ng/ml) in March, April, and in autumn. Optimal levels (above 60 ng/ml) on average were not recorded, even in the summer months.

A moderate direct correlation was discovered between levels of 25(OH)D₃ and the relative and absolute number of CD25+ and the relative number of CD8+, CD95+ (p < 0.05; weak direct relationship was detected between the level of 25(OH)D³ and the following parameters: number of lymphocytes, relative and absolute number of CD4+, CD16+, absolute number of CD8+, CD95+, phagocytosis completeness index, index NBT–test.

Conclusion. In infants with recurrent respiratory infections with n o signs of rachitis level of 25(OH)D₃ was almost two times lower than in their occasional ill peers, which may indicate extraosseal action of vitamin D, including the immune response influence. This necessitates determining the level of vitamin D in children with recurrent infections and its correction.