Abstract: Objective To compare the differences on the risk factors,symptoms and complications between sputum smear positive pulmonary tuberculosis and sputum smear negative pulmonary tuberculosis,so as to provide the scientific evidences for diagnosis,prognosis and the control of infectious sources. Methods A non matching case-control method,selection of activities during the period of January 2014 to December 2015 of sputum smear positive and smear negative pulmonary tuberculosis patients in 126 cases,76 patients were diagnosed as sputum smear positive pulmonary tuberculosis and 50 cases were smear negative pulmonary tuberculosis. All cases data were collected. χ2 values,odds raitios(OR),relative risk(RR) and 95% confidence interval were calculated respectively. The differences among the risk factors,symptoms and prognosis between the patients with smear positive pulmonary tuberculosis and smear negative pulmonary tuberculosis were analyzed by statistical method. Results There is no significant difference in the distributions of sex and occupation between the two groups. The single variable analysis showed that pulmonary cavities,hypoproteinem-ia,history with retreated pulmonary tuberculosis were independent risk factors being associated with smear positive pulmonary tuberculosis. The prevalence of expectoration,complication of pneumonia and anemia between the two groups had significant differences. Conclusions The risk factors of sputum smear positive pulmonary tuberculosis were pulmonary cavities,hypoproteinemia and history with retreated pulmonary tuberculosis. The incidence of expectoration,pneumonia or anemia of patients with sputum smear positive pulmonary tuberculosis were significantly higher than the cases with sputum smear negative pulmonary tuberculosis. Therefore,the sputum management of smear positive pulmonary tuberculosis with retreated pulmonary tuberculosis history,pulmonary cavities is important,and positiveprevention and early treatment of pneumonia or anemia will play a very crucial role in the diseases control and improvement of cure rate.

Key words: Sputum smear positive pulmonary tuberculosis, Sputum smear negative pulmonary tuberculosis, Risk factor, Symptom, Prognosis