Value Of GST in Diagnosis of Malignant Ple-ural Effusions

We meauserd pleural fluid and serum glutathion S-tranferase (GST) activity in 89 patients with ple-ural effusion and serum GST activity in IS healthy person choosen as control group. The cause of 27 pleural effusion was malignancy, and nonmalignant diseases were determined as the cause of 62 cases. Mean serum GST activity was 18.39±1.18 UIL in patients with malignant effusions. which was sig-nificantly higher than those in both nonmalignant cases (p<0.01) and control group (p<0.001). Ple-ural fluid GST level of malignant and nonmalignant effusions were 28.46±1.48 U1L and 10.59±0.87 1.11 L. respectively. The difference between the pleural fluid GST values of malignant and nonmalignant ef-fusions was statistically significant (p<0.001). The mean pleural fluid to serum GST ratio of patients with malignant effusion was also significantly hig-her than that of nonmalignant group. The specifity and sensitivity of the determination of pleural fluid GST level in excess of 20 Ull. in distinguishing ma-lignant effusions were 97 percent and 85 percent, respectively. These values for pleural fluid to serum GST ratio with the cutoff level of 1,4 were 87 per-cent and 78 percent. Our findings indicate that de-termination of GST activity in pleural fluid has a di-agnostic value in differential diagnosis of malignant eiliisions.