PURPOSE: Residual pleural thickening is common complication of tuberculous(TB) pleurisy and sometimes in parapneumonic effusion. The aim of this study was assessed the expression of metalloproteinases(MMPs) and tissue inhibitors of metalloproteinases(TIMPs), and then compared with amount of pleural fluid and pleural thickening.
METHODS: Patients with newly diagnosis of pleural fluid was enrolled from June 2004 to January 2005. MMP-1, -2, -8 and -9 and TIMP-1 and -2 were determined by ELISA in serum and pleural fluid. The amount of pleural fluid at the time of the first detection(T0) and pleural thickening at the time of the completion of treatment(T1) and the final follow-up(T2) were measured on the simple chest PA films.
RESULTS: The study included 39 patients with pleural effusion. Twenty-three was TB, 7 parapneumonic effusion, 7 malignant effusion, and 2 transudates. MMP-1, -8 and -9 concentrations of parapneumonic effusion(9.6±8.5 pg/mL, 8720.2±12594.4 ng/mL, 383.6±405.0 ng/mL) were significantly higher than others(TB 3.9±2.3, 199.0±443.6, 74.0±68.7; malignant 2.7±1.7, 0.2±0.2, 62.1±61.0; transudate 1.8±0.2, 0.02±0.02, 40.0±42.4). TIMP-1/total protein of parapneumonic effusion(8075.4±2095.5) was significantly higher than malignant pleural fluid(4447.3±1925.3). MMP-8/TIMPs and MMP-9/TIMPs of papapneumonic effusion were also significantly higher than others. TIMP-1 of TB pleural effusion(35704.1±12573.8) was significantly higher than malignant(21637.2±9452.7). In parapneumonic effusion, MMP-1 and MMP-8/TIMP-2 were positive correlations with amount of pleural fluid at T0, and MMP-2/total protein was negative correlation. There was no significant relations between MMPs or TIMPs and residual pleural thickening at T2(median follow-up period; 6 months). In TB effusion, 29% of patients had residual pleural thickening at T2. 50% of patients had residual pleural thickening at T2(median follow-up period; 6 months) and significant higher TIMP-2(43.0±16.6 ng/mL vs 34.8±0.4, p=0.002).
CONCLUSION: In conclusion, the relationship between several MMPs and TIMPs in the pleural effusion may have a role in the pathogenesis of parapneumonic effusions. TIMP-2 might be one of predicting factor of residual pleural thickening in TB pleurisy.
CLINICAL IMPLICATIONS: Several MMPs and TIMPs could be assisted in diagnosing of different causes of pleural fluid and TIMP-2, predicting of residual pleural thickening.
DISCLOSURE: An Chang Hyeok, None.