Abstract

Background: The macroenzyme form of aspartate aminotransferase (macro-AST) is formed by the binding of aspartate aminotransferase (AST) with immunoglobulins. Macro-AST excretion from serum is prolonged because of its high molecular weight, leading to increased AST activities. Because of the difficulty in detecting macro-AST through routine laboratory tests, affected patients often undergo repeated examinations, with associated anxiety. Methods: The macro-AST was precipitated by polyethylene glycol precipitation to eliminate the interference of macro-aspartate aminotransferase in the detection of aminotransferase, so as to assist in early clinical diagnosis and identification of macro-aspartate aminotransferase.
Results: Polyethylene glycol (PEG) precipitation method has successfully discovered macro-AST, which is a simple and efficient method and is conducive to the popularization of use in the laboratory.
Conclusions: This case highlights the importance of an accurate and efficient diagnosis of macroenzymes in the serum in order to prevent unnecessary healthcare utilization and also to decrease the psychological burden on the patient.

DOI: 10.7754/Clin.Lab.2025.250304