Transforming growth factor beta-1 as a predictor of fibrosis in tuberculous pleurisy.

BACKGROUND AND OBJECTIVE

To clarify the influence of transforming growth factor beta-1 (TGF-beta(1)) in the development of pleural thickening in tuberculosis (TB), the levels of TGF-beta(1) in pleural fluid and in serum of patients with pleural TB and transudative effusions were determined.

METHODS

TGF-beta(1) was quantified in 58 pleural fluid and serum samples of patients with TB (n = 50) or transudative effusions (n = 8). Pleural thickening evaluated by high-resolution CT was scored as 0 (<3 mm); 1 (>or=3 and <10 mm) or 2 (>or=10 mm).

RESULTS

The highest pleural fluid TGF-beta(1) levels before treatment for TB were observed in patients with a pleural thickness score of 2. Of the 14 patients with score 1, five regressed to 0, five progressed to 2, and four maintained 1. All 17 patients with score 2 maintained this evaluation. Patients who presented score 1 and progressed to 2 had higher TGF-beta(1) levels than those who maintained the same score or regressed (score 1 or 0). Patients with score 2 (before or after treatment) had higher TGF-beta(1) levels than those with score 0 or 1.

CONCLUSION

Pleural fluid and serum TGF-beta(1) levels were higher in patients with TB, with a correlation between pleural fluid TGF-beta(1) levels before treatment and the degree of pleural thickening. This finding suggests that TGF-beta(1) might be considered as a predictor of pleural thickening in pleural tuberculosis.