VITAMIN D STATUS IN PATIENTS WITH TUBERCULOSIS IN YAKUTIA

Material and methods: Enzyme immunoassay (EIA) concentrations of 25-hydroxycholecalciferol (25(OH)D) were studied in 88 patients with tuberculosis. Serum levels 25(OH)D were assessed using the following criteria: optimal level 30-100 ng/mL; subnormal level 20-30 ng/mL; vitamin D deficiency -10-20 ng/mL; severe deficiency - less than 10 ng/mL. For statistical processing, Student's unpaired t-test, Mann-Whitney, and Kruskall-Wallis tests were used. Cutoff for statistical significance of differences (p) was 5%. Results: Mean age of patients was 40,7 (16,1) years. Proportion of male patients was significantly larger (p=0.035). Levels of 25(OH)D in men were somewhat lower than in women, but the differences were statistically negligible. No statistically significant correlation was established between age and level of 25(OH)D (r=-0.037; p=0.729). Assessment of distributions of vitamin D levels against laboratory reference showed, that serum vitamin D level was optimal in 4.5% of patients, and 12.5% had subnormal levels of vitamin D (20 to 30 ng/mL). In 34% of patients, vitamin D level was graded as 'vitamin d deficiency' (10 to 19.9 ng/mL); 49% had 'severe vitamin D deficiency' (below 10 ng/mL). Conclusions: Results of this pilot study demonstrated the presence of marked vitamin D deficiency in patients with TB. Due to absence of control group, no comparisons of vitamin D levels between TB patients and general population could be made. Considering the role of vitamin D in the induction of innate antimicrobial immune response, further investigation is needed into the causes of deficiencies, opportunities to correct deficiencies in patients with TB, role of vitamin D in therapy of TB, and a role of vitamin D receptor gene polymorphism in Yakut ethnic group.