Correlation of quantitative assay of hepatitis B surface antigen and HBV DNA levels in asymptomatic hepatitis B virus carriers.
OBJECTIVE
This study was to elucidate the correlation between quantity of hepatitis B surface antigen (HBsAg) and hepatitis B virus (HBV) DNA levels in asymptomatic carriers.


METHODS
Based on the presence of the hepatitis B e antigen (HBeAg) and HBV DNA levels, 67 asymptomatic carriers were divided into four groups. HBV DNA was determined by hybridization (sensitivity 141 500 copies/ml) and polymerase chain reaction (PCR, sensitivity < 10 copies/ml). Cases of groups I (n = 18), II (n = 17) and III (n = 16) were negative for HBeAg and had HBV DNA levels of < 10 (PCR undetectable), 10 to 10 (PCR detectable) and > 10 copies/ml (hybridization detectable), respectively. Cases of group IV (n = 16) were positive for HBeAg and high HBV DNA levels (> 2 x 10 copies/ml). HBsAg was determined quantitatively by the ARCHITECT HBsAg assay.


RESULTS
Our data showed HBsAg levels were correlated with HBV DNA (r = 0.709; P < 0.001) on a log scale. The mean log HBsAg (IU/ml) of groups I, II, III and IV were 2.68 +/- 0.8, 2.93 +/- 1.03, 3.22 +/- 0.45, 4.83 +/- 0.19, respectively. That of group IV was significantly higher than the mean log HBsAg of any other group (P < 0.001). The best cut-off for HBsAg in differentiating group IV from other groups was 15 000 IU/ml with both sensitivity and specificity of 100%. That of group I was significantly lower than those of group III (P = 0.035) and IV (P < 0.001). The best cut-off in differentiating group I from the other groups was 1600 IU/ml with a sensitivity of 69.4% and a specificity of 66.7%.


CONCLUSIONS
Quantitative measurement of HBsAg titres may be an easy and economical reference for HBV replication in HBV carriers.
Division of Hepato-Gastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.
Chien-Hung
CH
Chen
Chuan-Mo
CM
Lee
Jing-Houng
JH
Wang
Hung-Da
HD
Tung
Chao-Hung
CH
Hung
Sheng-Nan
SN
Lu
D000328:Adult; D000368:Aged; D002353:Carrier State / Q000821:virology; D004279:DNA, Viral / Q000032:analysis*; D005260:Female; D006509:Hepatitis B / Q000235:genetics / Q000276:immunology / Q000821:virology*; D006514:Hepatitis B Surface Antigens / Q000032:analysis*; D006515:Hepatitis B virus / Q000235:genetics* / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009693:Nucleic Acid Hybridization / Q000379:methods; D016133:Polymerase Chain Reaction / Q000379:methods
D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens