ObjectiveTo observe the impacts of initial therapy on clinical outcome of patients with community-acquired thoracic infection by retrospective analysis. MethodsClinical data of acute community-acquired thoracic infection patients who met the British Thoracic Society diagnostic criteria were collected. The patients were divided into two groups according to whether adequate initial antibiotic therapy and pleural effusion drainage were performed, namely an adequate group (31 patients) and an inadequate group (17 patients). Clinical manifestations, inflammatory markers, hospital stay and hospital costs were analyzed between the two groups. ResultsFor age, gender, infection sites, and coincident diseases, there were no significant differences between the two groups. Compared with the inadequate group, temperature of the adequate group was significantly decreased, especially on hospital day 5, 6, 7[(37.4±0.1)℃ vs. (38.3±0.2)℃, P < 0.001; (37.4±0.1)℃ vs. (37.9±0.1)℃, P < 0.05; (37.4±0.1)℃ vs. (38.1±0.2)℃, P < 0.01]. The level of serum C-reactive protein (CRP) in first week was also significantly reduced in the adequate group[(123.1±13.8) mg/L vs. (182.7±25.3) mg/L, P < 0.05]. However, there were no differences in white cell counts, percentage of neutrophils, or erythrocyte sedimentation rate between the two groups in six-week follow-up. The adequate group had shorter hospital stay[(25±4) days vs. (34±4) days, P < 0.05] and lower hospital costs[(28 367±3 328) yuan vs. (43 334±7 134) yuan, P < 0.05] compared with the inadequate group. ConclusionsThe initial therapy with appropriate antibiotics and effective thoracic drainage can significantly decrease the temperature and CRP of patients with thoracic infection, as well as the cost of hospitalization and the length of stay. Our study reveals that the temperature which is lower than 37.5℃ on the 5th day of therapy and the CRP in the first follow-up week are sensitive predictors of initial treatment effect, which may be helpful to guide the following therapeutic strategies.