Mutations in the S gene and in the overlapping reverse transcriptase region in chronic hepatitis B Chinese patients with coexistence of HBsAg and anti-HBs

Abstract Background The mechanism underlying the coexistence of hepatitis B surface antigen and antibodies to HBsAg in chronic hepatitis B patients remains unknown. Aims This research aimed to determine the clinical and virological features of the rare pattern. Methods A total of 32 chronic hepatitis B patients infected by HBV genotype C were included: 15 carrying both HBsAg and anti-HBs (group I) and 17 solely positive for HBsAg (group II). S gene and reverse transcriptase region sequences were amplified, sequenced and compared with the reference sequences. Results The amino acid variability within major hydrophilic region, especially the “a” determinant region, and within reverse transcriptase for regions overlapping the major hydrophilic region in group I is significantly higher than those in group II. Mutation sI126S/T within the “a” determinant was the most frequent change, and only patients from group I had the sQ129R, sG130N, sF134I, sG145R amino acid changes, which are known to alter immunogenicity. Conclusions In chronic patients, the concurrent HBsAg/anti-HBs serological profile is associated with an increased aa variability in several key areas of HBV genome. Additional research on these genetic mutants are needed to clarify their biological significance for viral persistence.

Frequency and significance of concurrent presence of HBsAg and anti-HBs among Korean HBsAg-positive patients / 대한임상병리학회지

BACKGROUND: Although the development of antibodies(anti-HBs) against hepatitis B surface antigen(HBsAg) generally leads to the clearance of the infecting hepatitis B virus(HBV), anti-HBs reactivity has been reported in patients with chronic hepatitis. Some reports suggested that concurrent presence of HBsAg and anti-HBs was a common serologic pattern in HBV carriers, however, the others insisted concurrence was associated with evidence of viral replication and features of active inflammation. This study was to investigate the frequency and significance of concurrent presence of HBsAg and anti-HBs among Korean HBsAg-positive patients. METHODS: HBV serological markers were analyzed by Abbott Axym. Anti-HBs titer was assessed quantitatively using 6 standard calibrators(0, 10, 50, 100, 500 & 1,000 mIU/mL), and reported as positive when more than 10 mIU/mL. RESULTS: Of 959 consecutive HBsAg-positive patients who had simultaneous anti-HBs determinations, HBsAg and anti-HBs were found concurrently in 31(3.2%). Anti-HBs was quantitated 10-100 mIU/mL in 25(80.6%) and more than 100 mIU/mL in 6(19.4%) among 31 HBsAg-positive patients with concurrent presence of anti-HBs. HBeAg positive rate of concurrent HBsAg/anti-HBs-positive patients(15/22 or 68.2%) was higher than that of HBsAg-positive patients without anti-HBs(227/562 or 40.4%). Of 31 HBsAg-positive patients with concurrent anti-HBs, 15 were patients with chronic hepatits, 5 with primary hepatocellular carcinoma and 2 with liver cirrhosis. CONCLUSIONS: Concurrent HBsAg/anti-HBs-positive patients were found in about 3% of Korean HBsAg-positive patients and their anti-HBs titers were less than 100 mIU/mL in 80% of concurrent HBsAg/anti-HBs-positive patients. In patients with chronic hepatits B who possessed HBsAg and anti-HBs above 100 mIU/mL, infections of HBV variants with mutations in the envelope gene might be suspected.

Serum HBsAg and Anti-HBs Positive Rate among a City Health Center Visitors / 예방의학회지

Hepatitis B virus(HBV) infection is one of the major health problems in Korea and HBsAg positive rate was known to be about 5~15% in general population. This study was conducted to identify the positive rates of serum HBsAg and anti-HBs among community population regared as having high HBV vaccination rate than in previous decade, using EIA(Enzyme immunoassay) method, in Seo-Gu, Taegu, Korea. The study subjects were 1,160 who visited Seo-Gu Health Center for check-up serologic markers of hepatitis B. The data were obtained from the serologic test for hepatitis markers and questionnaire survey was conducted to obtain the general characteristics, vaccination history, past history of hepatitis and other liver disease , and exposure history to risk factors of hepatitis of the study subjects. The positive rates of HBsAg and anti-HBs were 5.2% and 62.4% respectively. The positive rates of HBsAg for male and female were 6.6% and 4.3% respectively. The age was divided into two groups as group I(less than 15 years old), group II(more than 16years old) according to the hypothesis that these two groups might be different in HBV vaccination rate. HBV vaccination rates for group I and II were 83.1% and 52.3%. The positive rates of HBsAg for group I and II were 2.6% and 6.5%. The positive rates of HBsAg for the vaccinated people of the group I and II were 2.2% and 3.5%, the positive rates of anti-HBs for the vaccinated people of the group I and II were 70.1% and 71.1% respectively. The most significant factor in positive rate of HBsAg was 'hepatitis carrier in family'. Multiple logistic regression analysis revealed that 'hepatitis history' and 'hepatitis carrier in family' were significant variables for positivity of HBsAg, and 'hepatitis B vaccination' was only a significant variable for positivity of anti-HBs.