| Objective To explore the risk factors and pathogenic bacteria characteristics of pulmonary tuberculosis patients complicated with pulmonary infection. Methods A total of 179 patients with pulmonary tuberculosis admitted to our hospital from March 2017 to March 2019 were included in this study and observed for concurrent pulmonary infection. Pulmonary alveolar lavage fluid and sputum samples from patients with pulmonary infection were collected for pathogenic bacteria isolation and identification. Logistic regression analysis was used to analyze the risk factors of pulmonary infection in patients with pulmonary tuberculosis. Results Among 179 cases of pulmonary tuberculosis, 82 cases had pulmonary infection, the infection rate was 45.81%. Logistic regression analysis showed that duration of disease≥4 years, concurrent diabetes mellitus, long-term use of glucocorticoids, long-term use of broad-spectrum antibiotics, retreatment of pulmonary tuberculosis and invasive operation were risk factors for pulmonary infection in pulmonary tuberculosis patients. There were 83 strains of pathogenic bacteria isolated from 82 patients with pulmonary infection, mainly Gram-negative bacteria, totally 58 strains, accounting for 69.88%. Conclusions Pulmonary infections in pulmonary tuberculosis patients are mainly caused by Gram-negative bacteria. The duration of disease≥4 years, concurrent diabetes mellitus, long-term use of glucocorticoids, long-term use of broad-spectrum antibiotics, retreatment of pulmonary tuberculosis and invasive operation are risk factors for pulmonary infection in pulmonary tuberculosis patients. |