Kaohsiung Journal of Medical Sciences (2015) 31, 384e385
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LETTER TO THE EDITOR
Clinical importance of serum hepatitis B surface antigen quantification in the natural history of chronic hepatitis B infection To the Editor, In a recent issue of the Kaohsiung Journal of Medical Sciences, we read with interest the article by Kuo et al , “Changing serum levels of quantitative hepatitis B surface antigen (HBsAg) and hepatitis B virus DNA in hepatitis B virus surface antigen carriers: A follow-up study of an elderly cohort”. The authors concluded that serum hepatitis B surface antigen (HBsAg) quantification was well correlated with hepatitis B virus (HBV) DNA in treatment-naı¨ve HBsAg carriers, and lower levels of HBsAg and HBV DNA might present an inactive HBV infection. Recent studies have demonstrated that there was a significant correlation between HBsAg level and cccDNA before and after antiviral therapy [2,3]. Additionally, it was reported that HBsAg levels might be useful for discriminating different chronic hepatitis B (CHB) phases. This relationship would allow the clinician to screen the natural history of HBV infection and predict treatment response in CHB patients . In comparing HBsAg level with HBV DNA, the ready availability and inexpensiveness of HBsAg quantification may encourage its use in clinical practice in the near future. We thank the authors for their comprehensive contribution. However, we would like to point out several concerns regarding this study from a methodological point of view . First, it would have been more relevant if the sample size of CHB patients was larger. Second, secretion of HBsAg could be strongly influenced by HBV genotype, therefore, it would have been better if the authors had discriminated and compared the patients according to their genotypes . Third, it was demonstrated that the HBsAg levels tended to decline in the order of advancing liver disease,
Conflicts of interest: All authors declare no conflicts of interest.
from chronic hepatitis to cirrhosis and to hepatocellular cancer, as well as from ChildePugh Class AeC [4,5]. It has also been reported in recent studies that HBsAg titers tend to decrease with age during long periods of immune pressure, in which some patients may eventually lose HBsAg; in some patients, however, liver disease can progress over time. From this point of view, a decline in HBsAg and HBV DNA levels may not mean an improvement in CHB. For this reason, it would have been better if the authors had compared HBsAg levels according to these parameters. We are of the opinion that the findings of Kuo et al  will lead to further research regarding the association between HBsAg titers and HBV DNA levels. It is important that HBsAg titers be considered along with other independent variables (e.g., age, liver fibrosis, cirrhosis) to provide the required information.
References  Kuo YH, Chang KC, Wang JH, Tsai PS, Hung SF, Hung CH, et al. Changing serum levels of quantitative hepatitis B surface antigen and hepatitis B virus DNA in hepatitis B virus surface antigen carriers: a follow-up study of an elderly cohort. Kaohsiung J Med Sci 2015;31:102e7.  Suh SJ, Bae SI, Kim JH, Kang K, Yeon JE, Byun KS. Clinical implications of the titer of serum hepatitis B surface antigen during the natural history of hepatitis B virus infection. J Med Virol 2014;86:117e23.  Park H, Lee JM, Seo JH, Kim HS, Ahn SH, Kim do Y, et al. Predictive value of HbsAg quantification for determining the clinical course of genotype C HBeAg-negative carriers. Liver Int 2012;32:796e802.  Chung KH, Kim W, Kim BG, Lee HY, Jin EH, Cho YR, et al. Hepatitis B surface antigen quantification across different phases of chronic hepatitis B virus infection using an immunoradiometric assay. Gut Liver 2015 Feb 26. http://dx.doi. org/10.5009/gnl14188 [Epub ahead of print].
http://dx.doi.org/10.1016/j.kjms.2015.04.004 1607-551X/Copyright ª 2015, Kaohsiung Medical University. Published by Elsevier Taiwan LLC. All rights reserved.
Letter to the Editor  Jang JW, Yoo SH, Kwon JH, You CR, Lee S, Lee JH, et al. Serum hepatitis B surface antigen levels in the natural history of chronic hepatitis B infection. Aliment Pharmacol Ther 2011; 34:1337e46.
Ergenekon Karagoz Department of Infectious Diseases and Clinical Microbiology, GATA Haydarpasa Training Hospital, Istanbul, Turkey
385 Alpaslan Tanoglu* Department of Gastroenterology, GATA Haydarpasa Training Hospital, Istanbul, Turkey *Corresponding author. GATA Haydarpasa Training Hospital, Department of Gastroenterology, Tibbiye Street No: 1, 34668, Uskudar, Istanbul, Turkey. E-mail address: [email protected]