Observational Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Nov 28, 2016; 22(44): 9836-9843
Published online Nov 28, 2016. doi: 10.3748/wjg.v22.i44.9836
Clinical features of HBsAg seroclearance in hepatitis B virus carriers in South Korea: A retrospective longitudinal study
Young Min Park, Seong Gyu Lee
Young Min Park, Hepatology Center, Department of Internal Medicine and Biomedical Research Center, Bundang Jesaeng General Hospital, Seongnam-si, Gyeonggi-do 13589, South Korea
Seong Gyu Lee, Department of Laboratory Medicine, Bundang Jesaeng General Hospital, Seongnam-si, Gyeonggi-do 13589, South Korea
Author contributions: Park YM collected and analyzed the data, drafted the manuscript, and approved the final version for publication; Lee SG participated in acquisition, analysis, and interpretation of the data on serum HBsAg levels.
Institutional review board statement: This study was approved by the Institutional Review Board of Bundang Jesaeng General Hospital (Seongnam-si, Gyeonggi-do, South Korea).
Informed consent statement: Informed consent was not obtained.
Conflict-of-interest statement: There are no conflicts of interest to report.
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: Young Min Park, MD, PhD, Hepatology Center, Department of Internal Medicine and Biomedical Research Center, Bundang Jesaeng General Hospital, 20, Seohyeon-ro 180 beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do 13589, South Korea. ymp1@outlook.com
Telephone: +82-31-7790676 Fax: +82-31-7790164
Received: June 28, 2016
Peer-review started: June 30, 2016
First decision: August 08, 2016
Revised: August 26, 2016
Accepted: September 28, 2016
Article in press: September 28, 2016
Published online: November 28, 2016
Abstract
AIM

To investigate the characteristic features of hepatitis B surface antigen (HBsAg) seroclearance among Korean hepatitis B virus (HBV) carriers.

METHODS

Carriers with HBsAg seroclearance were selected by analyzing longitudinal data collected from 2003 to 2015. The period of time from enrollment to the negative conversion of HBsAg (HBsAg-NC) was compared by stratifying various factors, including age, sex, hepatitis B e antigen (HBeAg), HBV DNA, sequential changes in the signal-to-cutoff ratio of HBsAg (HBsAg-SCR), as measured by qualitative HBsAg assay, and chronic liver disease on ultrasonography (US-CLD). Quantification of HBV DNA and HBsAg (HBsAg-QNT) in the serum was performed by commercial assay.

RESULTS

Among the 1919 carriers, 90 (4.7%) exhibited HBsAg-NC at 6.2 ± 3.6 years after registration, with no differences observed among the different age groups. Among these carriers, the percentages of those with asymptomatic liver cirrhosis (LC) and hepatocellular carcinoma (HCC) at registration were 31% and 7.8%, respectively. The frequency of HBsAg-NC significantly differed according to the HBV DNA titer and US-CLD. HBeAg influenced HBsAg-NC in the 40-50 and 50-60 year age groups. HBsAg-SCR < 1000 was correlated with an HBsAg-QNT < 200 IU/mL. A gradual decrease in the HBsAg-SCR to < 1000 predicted HBsAg-NC. Six patients developed HCC after registration, including two before and four after HBsAg-NC. The rate at which the patients developed new HCC after HBsAg seroclearance was 4.8%. LC with excessive drinking and vertical infection were found to be risk factors for HCC in the HBsAg-NC group.

CONCLUSION

HCC surveillance should be continued after HBsAg seroclearance. An HBsAg-SCR < 1000 and its decrease in sequential testing are worth noting as predictive markers of HBsAg loss.

Keywords: Hepatocellular carcinoma, Hepatitis B virus, Hepatitis B Surface antigen, HBsAg, Seroconversion, Hepatitis B e antigen, HBeAg, Liver cirrhosis

Core tip: In South Korea, where most hepatitis B virus carriers are infected with genotype C, hepatitis B surface antigen (HBsAg) seroclearance rate is 4.7%, and the incidence of hepatocellular carcinoma (HCC) after HBsAg loss is 4.8%. In patients with HBsAg seroclearance, the percentages of asymptomatic liver cirrhosis (LC) and HCC are 31% and 7.8% at enrollment, respectively. A signal-to-cutoff ratio of the qualitative HBsAg level of less than 1000 and its sequential decrease are worth noting as predictive markers of HBsAg loss. HCC surveillance should be continued after HBsAg seroclearance, particularly in patients with LC.