Th1/Th2 cytokine profiles differentiating tuberculous from malignant pleural effusions: A systematic review and meta-analysis

Review question / Objective: To clarify which one has a different predominance of Th1 and Th2 immune responses in malignant and tuberculous pleural effusions. We did a meta-analysis of the results published previously to assess the levels of Th1/Th2 cytokines in two types of pleural effusion and evaluated its ability to distinguish TPE from MPE. Condition being studied: Malignant and tuberculous pleural effusions are the two most common types of exudative pleural effusions, both of which can be seen with the typical accumulation of lymphocytes. Immune responses mediated by either the Th1 or Th2 subset dominate, depending on different types of pleural effusion. Thus, we performed a meta-analysis of all available studies to quantitatively evaluate the levels of Th1/Th2 cytokine profiles in TPE and MPE, as well as to assess the potential diagnostic value of these cytokines in discriminating TPE from MPE.