Immunotherapeutic efficacy of BCG vaccine in pulmonary tuberculosis and its preventive effect on multidrug-resistant tuberculosis

Abstract

To evaluate the effect and safety of BCG vaccine on initially treated pulmonary tuberculosis and its controlling effect on multidrug-resistant tuberculosis. All 360 volunteers with initially treated pulmonary tuberculosis of positive smear and culture were divided into immunotherapy group (180 cases, also BCG group) and control group (180 cases) at random pair. The patients in BCG group were treated with chemotherapy of a regimen of 2HRZ/2HR and immunotherapy with BCG for 4 months,and the first BCG vaccine was given a month after chemotherapy. Meanwhile, the patients in the control group were treated with chemotherapy of 2HRZ/4HR only. (1) The negative conversion rate of sputum smear in BCG group was 98.3% (177/180), and it was 97.2% (175/180) in control group. There was no significant difference between the two groups both at the ends of 4 and 6 months after treatment (chi2 = 0.1278, P > 0.05). (2) The positive conversion rate of sputum smear in BCG group was 2.3% (4/177), and it was 6.9% (12/175) in control group followed up for 5 years. The successful rate was 96.1% (173/180) in BCG group, and it was significantly higher than that of 90.6% (163/180) in control group (chi2 = 4.4643, P < 0.05). (3) In the 5-year follow up, bacteriologic result was similar to that of X-ray. (4) The occurrence rate of multidrug-resistant tuberculosis was 2.3% (4/177) in BCG group,significantly lower than that of 7.3% (13/178) in the control group (chi2 = 4.9513, P < 0.05). As an adjunct chemotherapy,immunotherapy with BCG vaccine should be helpful for patients with initially treated pulmonary tuberculosis. It would further strengthen the effects of chemotherapy and reduce the occurrence rate of multidrug-resistant tuberculosis.