Stratified Threshold Values of QuantiFERON Assay for Diagnosing Tuberculosis Infection in Immunocompromised Populations
Figure 2
QuantiFERON-TB GOLD results in culture-proven pulmonary tuberculosis subgroups stratified by absolute number of peripheral blood lymphocyte. (a) Numbers and ages of patients divided into eight subgroups based on peripheral lymphocytes. (b) Proportion of QFT results with eight subgroups. *: versus <300/mm3 category. &: versus <300/mm3 category, versus 300–500/mm3 category, and versus 500–700/mm3 category. #: versus <300/mm3 category, versus 300–500/mm3 category, versus 500–700/mm3 category, and versus 700–1000/mm3 category. $: versus <300/mm3 category, versus 300–500/mm3 category, versus 500–700/mm3 category, versus 700–1000/mm3 category, and versus 1000–1200/mm3 category. (c) Antigen-stimulated and mitogen-stimulated IFN-γ responses with lymphocyte count (IU/mL). a: Nil (background) IFN-γ concentration. b: Difference between the higher IFN-γ concentration after stimulation with either antigenic peptides ESAT-6 or CFP-10 and nil (background) IFN-γ concentration. c: Difference between the determined IFN-γ concentration after stimulation with mitogen and the nil (background) IFN-γ concentration.
