Retrospective Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jun 7, 2017; 23(21): 3876-3882
Published online Jun 7, 2017. doi: 10.3748/wjg.v23.i21.3876
Relationship between serum adenosine deaminase levels and liver histology in autoimmune hepatitis
Murat Torgutalp, Cumali Efe, Hakan Babaoglu, Taylan Kav
Murat Torgutalp, Cumali Efe, Hakan Babaoglu, Taylan Kav, Department of Gastroenterology, Hacettepe University School of Medicine, 06100 Ankara, Turkey
Author contributions: Torgutalp M designed and performed the research and wrote the paper; Efe C and Kav T designed the research and supervised the report; Babaoglu H contributed to the analysis.
Conflict-of-interest statement: We have no financial relationships to disclose.
Data sharing statement: No additional data are available.
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/
Correspondence to: Cumali Efe, MD, Department of Gastroenterology, Hacettepe University School of Medicine, 06100 Ankara, Turkey. drcumi21@hotmail.com
Telephone: +90-505-5025589 Fax: +90-312-2534615
Received: February 5, 2017
Peer-review started: February 8, 2017
First decision: March 3, 2017
Revised: March 13, 2017
Accepted: April 12, 2017
Article in press: April 12, 2017
Published online: June 7, 2017
Abstract
AIM

To evaluate the relationship between serum adenosine deaminase (ADA) levels and histological features in patients with autoimmune hepatitis (AIH).

METHODS

A total of 80 subjects (52 AIH cases and 28 healthy controls) were included in the study. Patients were diagnosed according to the simplified criteria suggested by the International Autoimmune Hepatitis Group. All of the cases had been diagnosed with AIH between 2010-2015 at Hacettepe University, Department of Gastroenterology. Serum blood samples were collected and stored at -80 °C until the biochemical estimation of ADA activity. The diagnosis of patients was confirmed by liver biopsy. Serum ADA > 20 U/L was considered to be high level.

RESULTS

Mean serum ADA levels were significantly higher in AIH patients than those in healthy controls (25.4 ± 9.6 U/L vs 12.8 ± 2.2 U/L, P < 0.001). Serum ADA levels > 20 U/L were found in 63.5% AIH patients and in 0% healthy controls (P < 0.001). Mean serum ADA levels were significantly increased in each stage of histological activity: 15.2 ± 3.5 U/L for patients with mild interface hepatitis, 23.1 ± 10.0 U/L for patients with moderate interface hepatitis and 30.9 ± 7.0 U/L for patients with severe interface hepatitis (P < 0.001). Correlation analysis showed that there was a positive association between serum ADA levels and histological activity (r = 0.71, P < 0.001). Receiver operating characteristic analysis suggested that 24.5 U/L was the optimum cut-off point of ADA level for severe interface hepatitis (sensitivity 88%, specificity 85.2%, area under the curve: 0.88).

CONCLUSION

Because of the positive correlation with inflammatory activity, serum ADA level may be a potential biomarker for predicting or monitoring histological activity in patients with AIH.

Keywords: Autoimmune hepatitis, Liver biopsy, Adenosine deaminase, Non-invasive method

Core tip: Autoimmune hepatitis (AIH) is a chronic liver disease which can cause cirrhosis. Liver biopsy is still used as the gold standard in determining grade of fibrosis and disease activity in AIH. However, it is an invasive and difficult-to-repeat method, with some minor and major complications. In this study, we aimed to compare AIH patients’ serum adenosine deaminase (ADA) level with histopathological features of liver biopsy. To our knowledge, this is the first study investigating serum ADA activity in AIH. We showed that ADA level was a useful laboratory parameter that reflected histological activity in AIH.