Background: Pulmonary tuberculosis (TB) patients frequently present with compromised nutritional and antioxidant status, which may impair immune clearance of Mycobacterium tuberculosis. Vitamin C (ascorbic acid) has antioxidant and immune-supportive properties and has been proposed as a low-cost adjunct to standard anti-tuberculosis treatment (ATT).
Objective: To evaluate the effect of vitamin C supplementation, given alongside standard ATT, on the rate of acid-fast bacilli (AFB) sputum smear conversion in newly diagnosed pulmonary TB patients during the intensive phase of treatment.
Methods: A randomized, parallel-group study was conducted in 80 newly diagnosed, sputum-smear-positive, ATT-naïve pulmonary TB patients aged 20–65 years. Participants were allocated to receive either vitamin C (1000 mg/day) plus standard ATT (n=40) or placebo plus standard ATT (n=40). Sputum AFB smears were examined every two weeks for two months. Categorical outcomes were compared using the chi-square test; continuous outcomes (serum vitamin C levels) were compared using an independent-samples t-test. Significance was set at P<0.05.
Results: All 40 patients (100%) in the vitamin C group achieved sputum conversion within the first month, compared with 8 of 40 (20%) in the placebo group; the remaining placebo patients converted in the second month. The difference in conversion rate between groups was statistically significant (P<0.05). Mean serum vitamin C levels rose substantially more in the vitamin C group than in the placebo group over the study period.
Conclusion: Vitamin C supplementation during the intensive phase of ATT was associated with significantly faster AFB sputum conversion in pulmonary TB patients. Given its low cost and mild side-effect profile, vitamin C may be a useful, inexpensive adjunct to standard TB treatment, though confirmation in larger, multi-centric trials is warranted.