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http://dx.doi.org/10.15324/kjcls.2021.53.2.188

Detection of Macro-Aspartate Aminotransferase (AST) in an Asymptomatic Patient with Persistent Elevation of AST  

Yang, Eun Ju (Department of Biomedical Laboratory Science, Daegu Haany University)
Lim, Sung Soo (Department of Laboratory Medicine, Chungbuk National University College of Medicine)
Shin, Kyeong Seob (Department of Laboratory Medicine, Chungbuk National University College of Medicine)
Publication Information
Korean Journal of Clinical Laboratory Science / v.53, no.2, 2021 , pp. 188-192 More about this Journal
Abstract
The persistent increase of aspartate aminotransferase (AST) due to the presence of a macro-AST can confuse diagnostic or therapeutic decisions in many clinical situations. In this study, we report a case of isolated and persistent AST-elevation without any clinical sign of dysfunction in organs such as the liver, skeletal muscle, cardiac muscle, etc. Despite various investigations, no definite cause for the elevation of AST could be found. With the help of polyethylene glycol (PEG) precipitation, we showed that macro-AST formation was responsible for the elevation of the AST titer in this case. Early recognition of macro-AST by PEG precipitation can prevent diagnostic confusion and unnecessary and even invasive tests.
Keywords
Elevation of AST; Macro-AST; Polyethylene glycol precipitation;
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