Repeat detection of Mycobacterium DNA in sputum for the diagnosis of pulmonary tuberculosis.

This study explores the application value of real-time fluorescence quantitative PCR for repeated detection of Mycobacterium DNA in sputum for the diagnosis of pulmonary tuberculosis (TB). A total of 111 patients who were ultimately clinically diagnosed with pulmonary tuberculosis and sought treatment at Bozhou People's Hospital from January 2019 to March 2021 were selected. Mycobacterium DNA in sputum was detected by quantitative real-time PCR. The patients with TB were divided into Groups 1, 2, and 3 according to the number of sputum DNA examinations for Mycobacterium TB after admission. Group 1 was tested once, Group 2 was tested twice, and Group 3 was tested 3 times. There were 61 patients with pulmonary TB in Group 1, 37 patients in Group 2 and 13 patients in Group 3. Among the 111 patients with TB, the overall positive rate of sputum culture was 59.46% (66/111). The positive rates of TB-DNA in sputum of Groups 1, 2, and 3 were 49.18% (30/61), 70.27% (26/37), and 84.62% (11/13), respectively, and the positive rate of TB-DNA in Group 1 was significantly lower than that in Group 2 and Group 3 (P < .05). Repeated detection of Mycobacterium TB-DNA in sputum can improve the positive rate of TB patients, and 2 consecutive tests may be more suitable for early diagnosis of TB patients.