Multicenter study of QuantiFERON^®-TB Gold Plus in patients with active tuberculosis

Area of Science:

• Immunology
• Infectious Diseases
• Diagnostics

Background:

• QuantiFERON-TB Gold Plus (QFT-Plus) is a next-generation interferon-gamma release assay for tuberculosis (TB) detection.
• QFT-Plus utilizes additional antigen tubes to stimulate both CD4+ and CD8+ T-lymphocyte responses, differentiating it from previous versions.

Purpose of the Study:

• To evaluate the diagnostic sensitivity of QFT-Plus in comparison to QuantiFERON-TB Gold In-Tube (QFT-GIT).
• To assess the performance of QFT-Plus in a population of adult patients diagnosed with active tuberculosis.

Main Methods:

• A multi-site study involving adult patients with culture-confirmed active TB across the US and Japan.
• Participants were either untreated or had received less than 14 days of anti-TB treatment.
• Sensitivity and agreement between QFT-Plus and QFT-GIT were calculated, excluding indeterminate results.

Main Results:

• Out of 164 enrolled participants, 159 and 157 tests were analyzed for QFT-GIT and QFT-Plus, respectively, after excluding nine indeterminate results.
• QFT-GIT demonstrated a sensitivity of 94.3% (150/159), while QFT-Plus showed a sensitivity of 93.02% (146/157).
• The difference in sensitivity between the two tests was not statistically significant (P = 0.16), with high overall test agreement (98.7%, κ = 0.89).

Conclusions:

• QFT-Plus exhibits comparable sensitivity to QFT-GIT for diagnosing active TB in adults.
• The findings suggest QFT-Plus is a reliable alternative for TB testing, offering similar diagnostic accuracy to its predecessor.