Macro-aspartate Aminotransferase: Misleading Finding in a Patient with Non-alcoholic Fatty Liver Disease&#x0D;

Neha Sharma,Gagan K Sood,Umar Darr,Amir Darr

doi:10.7759/cureus.5042

Abstract

Persistent elevation of aspartate aminotransferase (AST) activity in serum due to the presence of a macro-enzyme form of AST (macro-AST) may lead to diagnostic confusion in many clinical conditions, particularly in those associated with chronic liver disease. We present a case of macro-AST in a patient with non-alcoholic fatty liver disease in which polyethylene glycol precipitation confirmed the cause of disproportionately elevated AST as macro-AST.

Highlights

Macro-enzymes are high molecular mass complexes of plasma enzymes with immunoglobulins (e.g., IgG, IgA or IgM) or other plasma components [1]
We report a case of isolated AST elevation with non-alcoholic fatty liver disease due to the presence of macro-AST
The elevated AST level of 136 U/L was first noted in 2006, and other liver enzymes were within reference ranges

Summary

Introduction

Macro-enzymes are high molecular mass complexes of plasma enzymes with immunoglobulins (e.g., IgG, IgA or IgM) or other plasma components [1] They are formed as a result of immune dysregulation. We report a case of isolated AST elevation with non-alcoholic fatty liver disease due to the presence of macro-AST. The elevated AST level of 136 U/L was first noted in 2006, and other liver enzymes were within reference ranges. How to cite this article Sharma N, Darr U, Darr A, et al (June 29, 2019) Macro-aspartate Aminotransferase: Misleading Finding in a Patient with Non-alcoholic Fatty Liver Disease. The results were consistent with the presence of macro-AST (i.e., 97% of the activity is precipitated with PEG), confirming our diagnosis

Discussion

Conclusions

Disclosures