Case Report
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Dec 26, 2019; 7(24): 4414-4419
Published online Dec 26, 2019. doi: 10.12998/wjcc.v7.i24.4414
Isolated elevated aspartate aminotransferase in an asymptomatic woman due to macro-aspartate aminotransferase: A case report
Meng-Ru Zhan, Xu Liu, Ming-Yuan Zhang, Jun-Qi Niu
Meng-Ru Zhan, Xu Liu, Ming-Yuan Zhang, Jun-Qi Niu, Department of Hepatology, The First Hospital of Jilin University, Changchun 130021, Jilin Province, China
Author contributions: Zhan MR contributed to the manuscript drafting and reviewed the literature; Liu X was responsible for the revision of the manuscript; Zhan MR and Zhang MY collected the patient’s clinical data; Niu JQ designed the report and revised the manuscript; All authors issued final approval for the version to be submitted.
Informed consent statement: The study was reviewed and approved by the First Hospital of Jilin University Institutional Review Board. The patient and his family were offered written explanations prior to the start of treatment, and they provided consent.
Conflict-of-interest statement: The authors declare that they have no conflicts of interest.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Jun-Qi Niu, MD, PhD, Doctor, Professor, Research Scientist, Department of Hepatology, The First Hospital of Jilin University, No. 71, Xinmin Street, Changchun 130021, Jilin Province, China. junqiniu@aliyun.com
Telephone: +86-13756661205 Fax: +86-0431-88786006
Received: September 24, 2019
Peer-review started: September 24, 2019
First decision: November 11, 2019
Revised: November 26, 2019
Accepted: November 30, 2019
Article in press: November 30, 2019
Published online: December 26, 2019
Processing time: 92 Days and 6 Hours
Abstract
BACKGROUND

Macro-aspartate aminotransferase (AST), a macroenzyme, is a high-molecular mass complex formed by self-polymerization or association with other serum components that are difficult for the kidney to clear, leading to the isolated elevation of serum AST activity. Cases of macro-AST formation are rare, with only 3 published in the English language literature up to September 2019 in China. In this paper, we present a case in which an asymptomatic woman with persistent isolated elevated AST was confirmed as having macro-AST by the polyethylene glycol precipitation method.

CASE SUMMARY

A 34-year-old woman was referred to our clinic for elevated AST levels with normal levels of other liver-associated enzymes on November 12, 2018. Her AST level of liver function test had been abnormal for 7 mo before she came to the clinic. The patient was asymptomatic with a normal physical examination. There was no relevant family history and no alcohol consumption or smoking. She had a several-month history of traditional Chinese medical taking and had stopped it 1 year prior. The laboratory tests in our clinic showed only the elevation of AST (89.5 U/L) with no other significant abnormalities. We performed the precipitation technique with polyethylene glycol to confirm the presence of macro-AST. Then for almost a year, her AST level still fluctuated in the abnormal range.

CONCLUSION

This case highlights that clinical physicians should be familiar with this rare condition of persistent isolated AST elevation due to the presence of macro-AST to avoid unnecessary investigation and patient anxiety.

Keywords: Aspartate aminotransferase; Macroenzymes; Macro-aspartate aminotransferase; Polyethylene glycol precipitation method; China; Case report

Core tip: Here, we present a case in which an asymptomatic woman with persistent isolated elevated aspartate aminotransferase was diagnosed as having macro-aspartate aminotransferase, which was confirmed by the polyethylene glycol method; only 3 such cases have been published in the English language literature up to September 2019 in China. It is necessary for physicians to be sufficiently familiar with this condition to avoid repeated unnecessary check-ups.