Use of Pleural Fluid Interferon-gamma Enzyme-linked Immunospot Assay in the Diagnosis of Pleural Tuberculosis.

AIM to evaluate the diagnostic value of an interferon-gamma release assay (IGRA) with enzyme-linked immunospot (ELISPOT) method, T-SPOT.TB, in the diagnosis of pleural TB using pleural fluid mononuclear cells (PFMC). METHODS forty-eight subjects, presumed to have pleural TB with exudative pleural effusion by Light's criteria, dominated by mononuclear cells, had their pleural fluid specimen tested with T-SPOT.TB, Mycobacterial Growth Indicator Tube (MGIT) culture, and adenosine deaminase (ADA) activity. Other causes of pleural effusion such as heart failure, renal failure, hepatic cirrhosis, and malignancy were excluded. RESULTS the sensitivity, specificity, positive predictive value, and negative predictive value of the IGRA ELISPOT assay using PFMC for the diagnosis of pleural TB were 100%, 88.89%, 97.5%, and 100%, respectively. CONCLUSION IGRA with ELISPOT method performed on PFMC is useful for a rapid and reliable diagnosis of pleural TB in clinical practice, especially in area with high TB burden.