Levels of 25 hydroxy vitamin D of serum and broncho-alveolar lavage in patients with pulmonary tuberculosis

Abstract

Alteration of vitamin D is a risk factor for tuberculosis (TB). To evaluate the pulmonary and serum levels of 25-hydroxy vitamin D (25OHD) in patients with and without pulmonary TB. Two-stage study: the first part was retrospective cross-sectional 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. 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). 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.