Interferon-gamma release assay performance of pleural fluid and peripheral blood in pleural tuberculosis.

Abstract

BACKGROUND:

The diagnosis of pleural tuberculosis (TB) remains to be difficult. Interferon-gamma release assay (IGRA) is a promising method for diagnosing TB in low TB burden countries. The release of interferon-gamma (IFN-γ) by T lymphocytes increases at a localized site of infection with Mycobacterium tuberculosis antigen. This study aimed to examine the clinical accuracy of T-SPOT.TB on pleural fluid and peripheral blood for the diagnosis of pleural TB in high TB burden country.

METHODS:

168 subjects with pleural effusion were enrolled prospectively and examined with T-SPOT.TB on pleural fluid and peripheral blood samples simultaneously.

RESULTS:

The receiver operating characteristic (ROC) curve and cut-off value of pleural fluid T-SPOT.TB was established according to spot forming cells (SFC) between culture/biopsy-confirmed pleural TB group and no pleural TB group. The sensitivity of pleural fluid T-SPOT.TB and peripheral blood T-SPOT.TB was similar (96.3% and 92.7%, respectively) (P= 0.691). In contrast, the specificity of pleural fluid T-SPOT.TB (94.5%) was significantly higher than that of peripheral blood T-SPOT.TB (76.1%) (P=0.002). 2% (2/98) of pleural fluid T-SPOT.TB results were indeterminate.

CONCLUSION:

The diagnostic accuracy of peripheral blood T-SPOT.TB is low in high TB burden countries due to latent tuberculosis infection. Pleural fluid T-SPOT.TB is a relatively useful and supplementary test to explore pleural TB in high TB burden countries, but its diagnostic accuracy needs to be validated in further large scale research.

• Authors: Fei Liu, Mengqiu Gao, Xia Zhang, Fengjiao Du, Hongyan Jia, Xinting Yang, Zitong Wang, Liqun Zhang, Liping Ma, Xiaoguang Wu, Li Xie, Zongde Zhang
• Journal: PloS one (PLoS One) Vol. 8 Issue 12 Pg. e83857 ( 2013) ISSN: 1932-6203 [Electronic] United States
• PMID: 24386296 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Adenosine Deaminase

Topics

• Adenosine Deaminase (metabolism)
• Adult
• Aged
• Body Fluids (metabolism)
• Female
• Humans
• Interferon-gamma Release Tests (methods)
• Male
• Middle Aged
• Pleura (metabolism)
• ROC Curve
• Tuberculosis, Pleural (blood, diagnosis, metabolism)