Retrospective Cohort Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Jan 26, 2019; 7(2): 137-144
Published online Jan 26, 2019. doi: 10.12998/wjcc.v7.i2.137
Combination of serum gamma-glutamyltransferase and alkaline phosphatase in predicting the diagnosis of asymptomatic choledocholithiasis secondary to cholecystolithiasis
Yong Mei, Li Chen, Peng-Fei Zeng, Ci-Jun Peng, Jun Wang, Wen-Ping Li, Chao Du, Kun Xiong, Kai Leng, Chun-Lin Feng, Ji-Hu Jia
Yong Mei, Peng-Fei Zeng, Jun Wang, Chao Du, Kun Xiong, Kai Leng, Chun-Lin Feng, Ji-Hu Jia, Department of Hepatopancreatobiliary Surgery, the Third Affiliated Hospital of Zunyi Medical University, Zunyi 563000, Guizhou Province, China
Li Chen, Diagnostics Laboratory, Affiliated Hospital of Zunyi Medical University, Zunyi 563000, Guizhou Province, China
Ci-Jun Peng, Department of Hepatopancreatobiliary Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi 563000, Guizhou Province, China
Author contributions: Mei Y and Chen L contributed equally to this work; Mei Y, Chen L, Zeng PF and Peng CJ carried out the studies, participated in study design, and drafted the manuscript; Wang J, Li WP, Du C, Xiong K, Leng K, Feng CL and Jia JH participated in data collection and performed the statistical analyses; All authors read and approved the final manuscript.
Supported by the Guizhou Provincial Department of Health Science and Technology Fund, No. GZWJKJ2014-2-151; the Science and Technology Fund of Guizhou Province, No. QKH LH [2016] 7421; and the Zunyi Science and Technology Research and Development Fund, No. ZSKHS [2016] 06.
Institutional review board statement: The study was approved by the Ethics Committee of the Third Affiliated Hospital of Zunyi Medical University, No. ZSYYLL118.
Informed consent statement: All clinical data were collected with informed consent obtained from study participants.
Conflict-of-interest statement: All authors declare that they have no any conflicts of interest.
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: Kai Leng, PhD, Chief Doctor, Department of Hepatopancreatobiliary Surgery, the Third Affiliated Hospital of Zunyi Medical University, No. 98 Fenghuang Load, Zunyi 563000, Guizhou Province, China. lengkai4757zsyy@163.com
Telephone: +86-851-28923927 Fax: +86-851-28923927
Received: October 4, 2018
Peer-review started: October 4, 2018
First decision: October 18, 2018
Revised: November 22, 2018
Accepted: December 21, 2018
Article in press: December 21, 2018
Published online: January 26, 2019
Processing time: 114 Days and 19.2 Hours
Abstract
BACKGROUND

Gamma-glutamyltransferase (GGT) is one of the most important laboratory tests for the evaluation of liver damage. Through a long-term clinical observation of patients with secondary asymptomatic choledocholithiasis, we found that most patients had abnormal GGT serum levels.

AIM

To investigate the combination of serum GGT and alkaline phosphatase (ALP) in predicting the diagnosis of asymptomatic choledocholithiasis secondary to cholecystolithiasis.

METHODS

In this retrospective cohort study, the clinical data of 829 patients with cholecystolithiasis admitted to the Third Affiliated Hospital of Zunyi Medical College from August 2014 to August 2017 were collected. Among these patients, 151 patients had secondary asymptomatic choledocholithiasis and served as the observation group, and the remaining 678 cholecystolithiasis patients served as the control group. Serum liver function indexes were detected in both groups, and the receiver operating characteristic (commonly known as ROC) curves were constructed for markers showing statistical significances. The cutoff value, sensitivity, and specificity of each marker were calculated according to the ROC curves.

RESULTS

The overall incidence of asymptomatic choledocholithiasis secondary to cholecystolithiasis was 18.2%. The results of liver function indexes including serum aspartate aminotransferase, alanine aminotransferase, direct bilirubin and total bilirubin levels showed no significant differences between the two groups (P > 0.05). However, the serum GGT and ALP levels were significantly higher in the observation group than in the control group (P < 0.05). The ROC curve analysis showed that the area under the curve was 0.881 (95%CI: 0.830-0.932), 0.647 (95%CI: 0.583-0.711) and 0.923 (95%CI: 0.892-0.953) for GGT, ALP, and GGT + ALP, respectively. The corresponding cut-off values of GGT and ALP were 95.5 U/L and 151.5 U/L, sensitivity were 90.8% and 65.1%, and specificity were 83.6% and 59.8%, respectively. The sensitivity and specificity of GGT + ALP were 93.5% and 85.1%, respectively.

CONCLUSION

An abnormally elevated serum GGT level has an important value in the diagnosis of asymptomatic choledocholithiasis secondary to cholecystolithiasis. The combination of serum GGT and ALP has better diagnostic performance. As a convenient, rapid and inexpensive test, it should be applied in secondary asymptomatic choledocholithiasis routine screening.

Keywords: Asymptomatic choledocholithiasis; Gamma-glutamyltransferase; Cholecystolithiasis; Alkaline phosphatase; Diagnosis; Screening

Core tip: Secondary choledocholithiasis is a common disease in hepatobiliary surgery, and most cases do not have symptoms. Failure of timely diagnosis of choledocholithiasis leads to an increased incidence of postoperative residual stones and related complications. In this study, a total of 829 cholelithiasis patients were included, and the results suggest that an abnormally elevated serum gamma-glutamyltransferase level has an important value in the diagnosis of asymptomatic choledocholithiasis secondary to cholecystolithiasis. As a convenient, rapid and inexpensive test, serum gamma-glutamyltransferase levels should be tested in secondary asymptomatic choledocholithiasis routine screening.