Evaluation of immune responses in HIV infected patients with pleural tuberculosis by the QuantiFERON TB-Gold interferon-gamma assay.

Background: Diagnosis of tuberculous (TB) pleuritis is difficult and better diagnostic tools are needed. New blood based interferon-gamma (IFN-gamma) tests are promising, but sensitivity could be low in HIV positive patients. The IFN-gamma tests have not yet been validated for use in pleural fluid, a compartment with higher level of immune activation than in blood.