[Serum levels of solubule tumor necrosis factor (TNF) receptors in patients with pulmonary tuberculosis].

Tumor necrosis factor alpha (TNF-alpha) is released from cells of monocyte/macrophage lincage and mediates the development of a variety of clinical and pathomorphological features in various infectious diseases, autoimmune diseases and cancer. In the case of tuberculosis, it is suggested that the release of TNF-alpha in the affected regions and into the circulation could account for the pathological and clinical features such as the development of necrotic lesions and fever and weight loss in TB patients. In the present study, the levels of soluble TNF receptor type I (sTNFR type I) and type II (sTNFR type II) and TNF-alpha in the sera of patients with pulmonary TB were assayed, and we tried to know whether these levels have clinical significance in determining the disease activity in TB patients. The serum levels of both sTNFR types I and II were significantly higher in TB patients (n = 22) who were previously untreated than in the healthy control (n = 14): for sTNFR type I, 2.82 +/- 1.37 ng/ml vs. 1.40 +/- 0.33 ng/ml (p < 0.0001), and for sTNFR type II, 3.83 +/- 1.76 ng/ml vs. 1.62 +/- ng/ml (p < 0.0001). The serum levels of sTNFR types I and II in TB patients showed significant correlations with their serum levels of CRP. The serum levels of TNF-alpha in these TB patients was 2.21 +/- 1.72 pg/ml, whereas TNF-alpha was not detectable in the sera of 9 healthy control. The serum levels of sTNFR type I and II were significantly higher in cavitary TB (n = 17) than in non-cavitary TB (n = 5). When TB patients were treated with antituberculosis drugs and clinical improvements were achieved, the elevated levels of sTNFR type I and TNF-alpha in the sera of same 5 patients measured before starting treatment showed significant decline and the serum levels of sTNFR type II showed also declined, however, the decline was statistically not significant. From all the results obtained in this study, we conclude that the assay of the serum levels of sTNFR in TB patients is useful in the evaluation of the disease activity of TB.