Level of interferon gamma in the blood of tuberculosis patients

ABSTRACT

Interferon gamma [IFN- gamma], a cytokine produced by a variety of cells is involved in the immune response against M. tuberculosis. It activates the production of other cytokines and molecules that kill mycobacterium. IFN- gamma also has diagnostic role in identification of active and latent tuberculosis. To determine the level of IFN- gamma in the blood of TB patients. Ninety-one subjects were selected, including 54 active TB patients and 37 healthy controls. Among 54 TB patients, 27 had confirmed TB and 27 were clinically diagnosed as having TB. IFN- gamma concentration was determined in their blood by an ELISA technique. In TB patients, Mean +/- SD of IFN- gamma was 48.69 +/- 28.78 pg/ml while it was 12.99 +/- 5.70pg/ml in the control group [p <0.001]. Significant differences in the level of IFN- gamma were observed among confirmed TB patients, clinically diagnosed TB patients and the control group [Mean +/- SD 59.68 +/- 28.78, 36.85 +/- 24.76 and 12.99 +/- 5.70 pg/ml, respectively]. Furthermore, a significant negative correlation was observed between the concentration of IFN- gamma in TB patients and the duration of anti-tuberculosis therapy. IFN- gamma level was high in both clinically diagnosed and confirmed TB patients as compared to a control group. Measurement of IFN- gamma production is helpful to diagnose active tuberculosis, but further research is required