Immunoassay for the in vitro qualitative and quantitative determination of hepatitis B e antigen (HBeAg) in human serum and plasma. The assay can be used as an aid for the diagnosis and monitoring of patients with hepatitis B viral infection.
Hepatitis B is a potentially life threatening liver infection caused by the hepatitis B virus (HBV). It is transmitted through contact with blood or other body fluids of an infected person.1 The disease is not always self limiting: in adults approx. 5 % of acute infections will follow a chronic course of varying degrees of severity; infants will develop chronic hepatitis B in up to 95 % of the cases.1
Approximately 300 million people are estimated to be living with HBV Infection. In 2019, hepatitis B resulted in an estimated 820 000 deaths, mostly from cirrhosis and hepatocellular carcinoma (primary liver cancer).1
HBeAg is a product of the pre-C/C gene that is found in hepatocytes during proliferation of HBV and is an important diagnostic tool to determine the status of ongoing HBV infections. The detection of HBeAg is generally associated with the presence of large quantities of virus as it is a surrogate of viral replication.2-4 HBeAg can be detected in serum shortly after hepatitis B s antigen (HBsAg) during acute HBV infections and when the infection is self-limited, usually disappears before HBsAg, when alanine aminotransferase (ALT) levels peak, followed by the presence of the corresponding antibody (anti‑HBe).3-5
HBeAg can usually be detected when viral replication is high, both in self-limited infections and in chronic hepatitis B; its presence for more than 10 weeks is indicative of a transition to persistent infection. HBeAg seroconversion to anti‑HBe suggests the end of active viral replication and is therefore associated with clinical resolution (self-limited) or remission (chronic disease), marking a transition from the immune-active phase of the disease to the inactive carrier state.3-6
HBV infections can occur without detectable HBeAg due to infection with HBV variants containing precore stop codon mutants; while the virus can no longer produce HBeAg, disease activity is ongoing and anti‑HBe may be present.3,7,8
HBeAg seroconversion is a marker for treatment response and a goal of antiviral therapy in HBeAg positive patients.7,9 As such, quantitative measurement of HBeAg can provide guidance to physicians regarding cessation of antiviral therapy.10
HBeAg is considered an important indicator for risk of mother-to-child transmission11, where the transmission of HBV from HBeAg positive mothers to newborns plays a significant role.12 Clinical guidelines recommend to screen all pregnant women with HBeAg serving as a surrogate marker for HBV replication when no access to HBV DNA testing is available.13
The Elecsys HBeAg quant test is, therefore, meaningful in association with the anti‑HBe test for monitoring the course of HBV infection and the effect of treatment for chronic hepatitis B.3,4,6,7,13
| Systems | cobas® e 411 analyzer cobas® e 601 / cobas® e 602 modules |
cobas® e 402 / cobas® e 801 analytical units |
|---|---|---|
| Testing time | 18 minutes | |
| Test principle | One-step sandwich assay | |
| Calibration | 2-point | |
| Traceability | Standardized against the 1st WHO International Standard Hepatitis B virus e antigen (HBeAg), code 129097/12 of the Paul-Ehrlich-Institut, Langen (Germany). | |
| Sample material | Serum collected using standard sampling tubes or tubes containing separating gel. Li‑heparin, Na‑heparin, K2‑EDTA, K3‑EDTA, ACD, CPD, CP2D, CPDA and Na‑citrate plasma. Plasma tubes containing separating gel can be used. |
|
| Sample volume | 35 µL | 21 µL |
| Reagent Onboard stability | 8 weeks | 16 weeks |
| Intermediate precision in positive samples | cobas® e 411: CV 5.2 – 7.4 % |
cobas® e 402/801: CV 5.6 – 7.5 % |
| Limit of Blank | 0.05 IU/mL | |
| Limit of Detection | 0.10 IU/mL | |
| Limit of Quantitation | 0.20 IU/mL | |
| Measuring range | Linear: 0.10 IU/mL - 120 IU/mL |
|
| Extended measuring range | 1:20 dilution: 2400 IU/mL | 1:30 dilution: 3600 IU/mL |
| Result interpretation | < 0.23 IU/mL = non-reactive (negative for HBeAg) ≥ 0.23 IU/mL = reactive (positive for HBeAg) |
|
| Relative sensitivity | 100 % (310 patients with acute or persistent HBV infection) | |
| Relative specificity | 100 % (routine (n = 1001), blood donors (n = 1000), hospitalized patients n = 300), dialysis (n = 100) and pregnant women (n = 100)) |
|
| Analytical specificity | No cross-reactions with HAV, HCV, HEV, CMV, EBV, HSV, HIV, E. coli, Toxoplasma gondii, Rubella and Treponema pallidum | |
Learn more about Hepatitis B serologic profiles and proposed clinical Use Cases.
References
