Relationship between Serum Interferon Gamma Level with Sputum Positivity of Acid-Fast Bacillus in New Case Pulmonary Tuberculosis

Introduction. Interferon gamma (IFN-γ) is an important cytokine to eliminate M. tuberculosis. Level of IFN-γ in tuberculosis (TB) patients increase in the beginning of disease and will decrease after therapy. This study aims to know the association between IFN-γ serum level and acid-fast bacilli (AFB) sputum positivity. Methods. A cross sectional study was conducted among TB patients in Wahidin Sudirohusodo and Labuang Baji hospital, Makassar from June 2013 until March 2014. Sample consisted of plasma from TB patients and healthy subjects which were measured with ELISA technique. Data analysis was performed using Mann-Whitney and Kruskal-Wallis test with SPSS for Windows version 17.0. Results. Total study samples was 88, which was consisted of 4 subject with negative AFB, 7 subjects with positive 1 AFB, 17 subjects with positive 2 AFB, and 22 subjects with positive 3 AFB. Level of IFN-γ serum tended to increase with AFB sputum positivity. There was a statistically significant association between level of IFN-γ serum and AFB sputum positivity (p<0,001). Conclusions. Level of IFN-γ serum tends to increase with AFB sputum positivity.