Levels of 25 hydroxy Vitamin D of serum and Broncho-Alveolar Lavage in patients with pulmonary tuberculosis

Abstract

Background: Alteration of vitamin D is a risk factor for tuberculosis (TB). Aim: To evaluate the pulmonary and serum levels of 25hydroxy vitamin D (25OHD) in patients with and without pulmonary TB. Methods: Two-stage study: the first part was retrospective crosssectional and the second prospective. Those > 18 years of age who underwent fiberoptic bronchoscopy for suspected pulmonary TB and in whom the infection was confirmed were included. Patients with another type of infection without TB and non-infectious diseases were taken as controls for the first stage and infectious controls without TB in the prospective phase. The measurement of 25OHD was performed by ELFA (enzyme-linked fluorescence assay). The Kruskal-Wallis test was used to evaluate association, considering a value of p < 0.05 to be significant. The data were processed with the SPSS version 23 program. Results: The total sample was 77 patients (35 in the first stage and 42 in the second). The characteristics between the groups were homogeneous. Serum (second phase) and broncho-alveolar lavage (first and second phase) levels of 25OHD were lower in TB patients compared to controls and were independent of serum calcium level (serum: 22.4 ng/mL vs 33 ng/mL, p = 0.006 and broncho-alveolar lavage: 9.7 ng/mL vs 12.2 ng/mL; p = 0.012). Conclusions: There was a significant difference between the levels of 25OHD in both serum and broncho-alveolar lavage in patients with pulmonary TB in relation to their controls.