[Clinical significance of cytokine measurement in pleural effusion].

We measured the activity of adenosine deaminase (ADA) and the concentration of interleukin-1 beta (IL-1 beta), interleukin-2 (IL-2), interleukin-8 (IL-8), tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) in the pleural effusions from 28 patients with tuberculosis, 30 with neoplastic diseases, 25 with bacterial infections and 18 with congestive heart failure or liver cirrhosis. The levels of ADA (83.0 +/- 32.1 IU/L) and IFN-gamma (795.0 +/- 666.4 pg/ml) in tuberculous effusions were significantly higher than those in other groups (p < 0.0001). IL-1 beta level in the effusions of bacterial infections (265.2 +/- 379.2 pg/ml) was higher than that in other groups (p < 0.0001). TNF-alpha level in the effusions of tuberculosis (31.7 +/- 36.7 pg/ml) and bacterial infections (69.5 +/- 232.9 pg/ml) was higher than that in other groups. IL-8 level of exudative effusions was higher than that of transudates. IL-2 was only present in 4 effusions from tuberculosis and 1 effusion from bacterial infections. Diagnostic utilities of cytokines and ADA for tuberculous effusion were evaluated using receiver operating characteristics (ROC) curve analysis. The cut-off points of ADA, IL-1 beta, IL-8, TNF-alpha and IFN-gamma determined in this analysis were 54 IU/L, 5.5 pg/ml, 405 pg/ml, 4.5 pg/ml and 28 pg/ml, respectively and the sensitivity and the specificity of them were 88.0% and 95.9%, 19.1% and 74.1%, 57.1% and 63.2%, 81.0% and 77.2%, and 96.2% and 98.5%, respectively. In ADA, TNF-alpha and IFN-gamma, the areas under the curve (AUC) that represent the diagnostic accuracy were 0.968, 0.719 and 0.993, respectively. AUC of IFN-gamma was significantly higher than that of ADA or TNF-alpha. In tuberculous pleural effusion, IFN-gamma was significantly correlated with TNF-alpha, IL-1 beta and ADA. The correlation was also present between TNF-alpha and ADA.