Tuberculosis is a respiratory infectious disease caused by Mycobacterium tuberculosis infection. After standardized and effective treatment, the cure rate reaches more than 90%, but there are still some relapses, and the main reasons are as follows: 1. The initial course of treatment for tuberculosis is not enough, and the short course of therapy for some complex tuberculosis is not long enough, requiring 9-12 months. It has been reported in the literature that after 6 months of short-term therapy for pulmonary tuberculosis, there is still a 1-2% probability of relapse. Among the relapsed cases, a significant proportion of them belong to complex tuberculosis, and the treatment time is not properly extended. 2, the use of drugs is not standardized, and insufficient combination of drugs is a relatively common cause of tuberculosis relapse, so the treatment of tuberculosis needs to be strictly in accordance with the short course of therapy, using a treatment plan that includes four drugs such as isoniazid, rifampin, pyrazinamide and ethambutol. 3, drug-resistant tuberculosis The presence of drug-resistant strains of the infected tuberculosis bacteria requires timely adjustment of the drug regimen based on drug sensitivity tests. In addition, the patient’s low immunity is one of the main factors for the recurrence of tuberculosis.