RESUMO
Macroenzymes are normal enzymes complexed with an immunoglobulin (usually IgG, rarely IgA or IgM). A number of macroenzymes have been reported in the literature. Among them, macro-AST has been detected in diseases such as acute and chronic hepatitis, various malignancies and autoimmune diseases, but usually not associated with any specific disease. We report a case of elevated AST activity in serum due to marco-AST formation in a female with chronic hepatitis C which was confirmed by AST isoenzyme electrophoresis. To our knowledge, this is the first report of macro-AST occurred in chronic hepatitis patient in Korea.
Assuntos
Feminino , Humanos , Pessoa de Meia-Idade , Aspartato Aminotransferases/sangue , Hepatite C Crônica/enzimologia , Isoenzimas/sangueRESUMO
Serum aspartate aminotransferase (AST) is a common enzyme for the evaluation of the hepatic, muscular and cardiac diseases and is produced also at kidney, brain, pancreas, lung, leukocytes, erythrocytes, etc. The elevation of its activity is usually caused by the necrosis of hepatocytes when there are not muscular injuries or myopathies. Recently, it is found that AST can exist as a macroenzyme by forming a complex with an immunoglobulin and this complex is erroneously considered to indicate the presence of liver disease as a result of elevation of AST activity on routine blood chemistry analysis. We experienced the patient with isolated AST elevation due to the formation of AST-mmunoglobulin complex confirmed by AST isoenzyme electrophoresis (EP).