Format

Send to

Choose Destination
J Clin Virol. 2006 Nov;37(3):206-12. Epub 2006 Aug 8.

Quantitative analysis of HBsAg, IgM anti-HBc and anti-HBc avidity in acute and chronic hepatitis B.

Author information

1
Department of Microbiology and Virology, University of Brescia, Spedali Civili Brescia, Piazza Spedali Civili 1, 25123 Brescia, Italy.

Abstract

BACKGROUND AND OBJECTIVES:

We evaluated hepatitis B virus (HBV) serological markers by novel, quantitative immunoassays in order to study their behaviours and possible role in the various phases of HBV infection.

STUDY DESIGN:

The quantitative determination of HBsAg and anti-HBc/IgM by chemiluminescent immunoassays (Abbott Architect) and the calculation of anti-HBc avidity index have been carried out on repository specimens from patients with acute or chronic hepatitis B.

RESULTS:

In acute hepatitis the levels of HBsAg were generally >10,000 UI/mL and decreased sharply in the recovery phase. In 35 anti-HBe-positive chronic hepatitis cases HBsAg levels were generally lower than 10,000 UI/mL (mean: 2655), whereas in five HBeAg-positive chronic hepatitis patients the mean value was 78,756 UI/mL and 90% of specimens exceeded 10,000 UI/mL. The lowest values (mean: 1029 IU/mL) were found in the seven patients with minimal hepatic damage. IgM anti-HBc antibodies were positive in all acute cases and in 68/207 samples (32.85%) from patients with chronic hepatitis, with significantly lower levels (average sample/cutoff (S/CO) ratio: 2.95 in chronic cases versus 25.96 in acute cases; p<0.005). A S/CO value of 10 for anti-HBc IgM had a 100% negative predictive value and a 99.13% positive predictive value for acute hepatitis B. The study of anti-HBc avidity by an experimental procedure showed that an avidity index (AI) threshold of 0.7 had a good efficacy to discriminate the cases of chronic hepatitis, among whom only 2 specimens out of 193 (1.04%) had an AI<0.7.

CONCLUSION:

The quantitative determination of HBsAg, anti-HBc/IgM and anti-HBc avidity provides additional information and may be useful in the differential diagnosis of acute and chronic HBV infections and in the follow-up of chronically infected patients.

PMID:
16893678
DOI:
10.1016/j.jcv.2006.06.011
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center