There has been 9.4 million tuberculosis (TB) that could result in 1.8 million deaths . TB has become an increasingly serious global public health problem and was regarded as a major cause of illness and death. TB treatment was challenging with the emergence of multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) . However, there was still lack of ideal and available chemotherapies for the treatment of TB. It was urgent and valuable to develop novel anti-tuberculosis treatment (ATT) to control the global tuberculosis epidemic.

            Vitamin D deficiency was widespread in active tuberculosis. Vitamin D deficiency was associated with an increased susceptibility to tuberculosis infection and increased the rate of conversion from latent to active tuberculosis . Thus, vitamin D might have the capability to decrease the risk of TB infection, prevent the progression from latent to active TB, decrease the duration and to improve treatment effectiveness as an adjunct to antimicrobial therapy. Vitamin D had some potential in improving the anti-mycobacterial activity in monocytes, and it was partly mediated by the upregulation of the antimicrobial peptide LL-37. Vitamin D was found to increase the response to antimicrobial therapy for pulmonary TB .

            Accumulating relevant RCTs showed that vitamin D supplementation failed to significantly improve sputum smear-negative conversion rates, and to reduce erythrocyte sedimentation rate (ESR). A Study published in British Pulmonary Medicine in  total of 1787 patients with active PTB receiving vitamin D supplementation along with standard anti-tuberculosis regimen were included in the eight trials with different doses of vitamin D ranging from 1000 IU/day to 600,000 IU/month at different intervals. Primary analysis revealed that vitamin D supplementation increased the proportion of sputum smear and culture conversions but did not improve the time to sputum smear and culture conversions. In the secondary analysis, vitamin D improved serum 25(OH)D, plasma calcium concentration, lymphocyte count, and chest radiograph , but had no impact on adverse events, mortality and other indicators(TB score, BMI, mean mid-upper arm circumference, weight gain, CRP, ESR, and other blood cells).