DETERMINATION OF PLASMA ALPHA-GLUTATHIONE S-TRANSFERASES IN PATIENTS WITH HCV-RELATED CHRONIC INFECTION - ITS SIGNIFICANCE AND POSSIBLE CLINICAL RELEVANCE

Aims/Background. Alpha-glutathione S-transferases (or-GST) are the cyt oplasmatic class of enzymes responsible for cellular detoxifying proce sses. We evaluated the plasma alpha-GST activity in relation to chroni c infection caused by hepatitis C virus (HCV). Methods: Eighteen anti- HCV-negative healthy subjects (controls), 32 anti-HCV-positive subject s with a constant normality of alanine aminotransferases (ALT) and gam ma-glutamyl transpeptidase (gamma-GT) levels (''apparently healthy car riers''), and 85 patients with HCV-related chronic liver disease (40 c hronic hepatitis, 27 cirrhosis, and 18 with hepatocellular carcinoma) were studied. We assayed plasma alpha-GST in all subjects upon their e ntry into the study; and every 6 months for 3 years in the control gro up and in anti-HCV apparently healthy carriers. Results. Alpha-GST val ues were significantly higher than normal values in 57% of the 21 HCV- RNA-positive apparently healthy carriers and in none of 11 persistentl y HCV-RNA-negative subjects; the highest increment of alpha-GST was do cumented in patients with chronic hepatitis. We did not observe correl ation among HCV-RNA, histological activity, gamma-GT and ALT or alpha- GST values. Conclusions: Therefore, the increment of plasma alpha-GST indicates a liver involvement even when ALT levels are normal. This ma y be clinically relevant to ''apparently healthy carriers'' whose plas ma alpha-GST values, when increased, might need further evaluation.