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

지속적으로 AST가 증가된 무증상 환자에서 Macro-AST의 검출

  • 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)
  • 양은주 (대구한의대 임상병리학과) ;
  • 임성수 (충북대학교 의과대학 진단검사의학교실) ;
  • 신경섭 (충북대학교 의과대학 진단검사의학교실)
  • Received : 2021.04.07
  • Accepted : 2021.05.01
  • Published : 2021.06.30

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.

Macro-AST의 존재로 인해 AST가 지속적으로 증가한 경우 진단 및 치료에 많은 혼란을 야기할 수 있다. 이 연구에서 저자들은 간, 횡문근, 심장근육 등과 같은 기관에 어떤 증상도 없이 지속적으로 AST만 증가한 환자의 증례를 보고하고자 한다. 다양한 검사를 시행하였음에도 불구하고 AST의 증가 원인을 밝히지 못하였지만 polyethylene glycol (PEG) 침전법을 통해 macro-AST가 AST의 증가 원인임을 밝혔다. 결론적으로 간편한 PEG 법에 의한 macro-AST의 조기 검출은 진단에서 혼란이나 불필요한 추가 검사 또는 침습적인 검사를 막을 수 있을 것이다.

Keywords

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