Macro AST - cause of asymptomatic aspartate aminotransferase elevation - case report

Abstract

Measurement of serum aspartate aminotransferase (AST, SGOT, serum glutamic-oxaloacetic transaminase) activity is one of the most common biochemical tests. In rare cases AST binds to immunoglobulins and forms macroenzyme called macro AST, which has high molecular weight and longer biological half-time.

This causes persistent elevation of AST activity without clinical correlate. Patients with unexplained serum AST elevation usually undergo detailed investigation including invasive and costly procedures.

Early identification of macroenzymes by serum or plasma precipitation with polyethylene glycol could reduce the number of costly and invasive investigations.

Keywords

• aspartate aminotransferase
• macroenzyme
• macro AST