title: Sputum endothelin-1 level is associated with active pulmonary tuberculosis and effectiveness of anti-tuberculosis chemotherapy.
abstract: Pulmonary tuberculosis (TB) is a major global health problem. Endothelin (ET)-1 is an important pro-inflammatory factor in the airways, which acts as a chemoattractant and an upregulator of other inflammatory mediators. In the present study, the association of the sputum ET-1 level with active pulmonary TB and the effectiveness of anti-TB chemotherapy was explored for the first time. A total of 56 newly diagnosed patients with active pulmonary TB, 56 age- and gender-matched TB-free controls, and 43 subjects with latent TB were recruited to the study. Patients in the active TB group received standard anti-TB chemotherapy. Sputum samples were collected from all study subjects at baseline (day 0) and on days 1, 2, 4, 6, 10 and 14 of treatment for the active TB group and the ET-1 level was determined by enzyme-linked immunosorbent assay. The sputum ET-1 level in the active TB group was significantly higher than those in the latent TB and the non-TB groups at baseline. Following adjustment for confounders such as age, gender, severity of clinical presentation, plasma ET-1 level and comorbidities that might affect the sputum ET-1 level, multivariate logistic regression analysis revealed that sputum ET-1 level was an independent indicator for active pulmonary TB. In the active TB group during anti-TB chemotherapy, decrements in the sputum ET-1 level were in significant correlation with decrements in the number of colony-forming units and increments in the time to positivity in a Mycobacteria Growth Indicator Tube assay. In conclusion, this study indicates that an elevated sputum ET-1 level is an independent indicator of active pulmonary TB and suggests that decrements in the sputum ET-1 level could reflect the effectiveness of anti-TB chemotherapy.
authors.affiliation: Cancer Research Institute, Central South University, Changsha, Hunan 410078, P.R. China; Department of Thoracic Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China; Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Changsha, Hunan 410078, P.R. China; Key Laboratory of Carcinogenesis, Ministry of Health of Hunan Province, Changsha, Hunan 410078, P.R. China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Thoracic Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China.
authors.forename: Jingqun
authors.initials: J
authors.lastname: Tang
authors.affiliation: Department of Thoracic Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China.
authors.forename: Ranran
authors.initials: R
authors.lastname: Wang
authors.affiliation: Department of Thoracic Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China.
authors.forename: Chen
authors.initials: C
authors.lastname: Chen
authors.affiliation: Department of Thoracic Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China.
authors.forename: Shichuan
authors.initials: S
authors.lastname: Tan
authors.affiliation: Department of Thoracic Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China.
authors.forename: Fenglei
authors.initials: F
authors.lastname: Yu
authors.affiliation: Cancer Research Institute, Central South University, Changsha, Hunan 410078, P.R. China; Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Changsha, Hunan 410078, P.R. China; Key Laboratory of Carcinogenesis, Ministry of Health of Hunan Province, Changsha, Hunan 410078, P.R. China.
authors.forename: Yongguang
authors.initials: Y
authors.lastname: Tao
authors.affiliation: State Key Laboratory of Medical Genetics, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410078, P.R. China.
authors.forename: Yunping
authors.initials: Y
authors.lastname: Li
keywords: biomarker; endothelin-1; pulmonary tuberculosis; sputum; tuberculosis