Elecsys^® Anti-HBc II

Immunoassay for the qualitative determination of total antibodies against hepatitis B core antigen (HBcAg)

Immunoassay for the qualitative determination of total antibodies against hepatitis B core antigen (HBcAg)

The hepatitis B virus (HBV) consists of an external envelope (HBsAg) and an inner core (HBcAg). The hepatitis core antigen comprises 183 – 185 amino acids.¹ During an infection with HBV, antibodies to HBcAg (anti-HBc) are generally formed soon after the appearance of HBsAg, the initial antibody being mostly IgM class, which then declines in titer as levels of anti-HBc IgG start increasing.² Anti-HBc (total) positivity persists in persons who have recovered from HBV infection and in those who progress to chronic HBV infection.^3,4 Accordingly, they are an indicator of existing or past HBV infection.⁵ In rare cases, HBV infection can also run its course without the appearance of immunologically detectable anti-HBc (usually in immunosuppressed patients).⁷ Anti-HBc is not produced after vaccination.^4,7

Due to the persistence of anti-HBc following HBV infection, screening for anti-HBc can be used to identify previously infected individuals.⁸ Determination of anti-HBc in association with other hepatitis B tests permits the diagnosis and monitoring of HBV infections.^3,4 In the absence of other hepatitis B markers (HBsAg-negative persons), anti-HBc may be the only indication of an existing HBV infection.^5,9

Elecsys^® Anti-HBc II

Systems

cobas e 411 analyzer, cobas e 601 / cobas e 602 modules, cobas e 801 module
Testing Time

27 minutes
Test principle

2-step competitive assay with pretreatment
Calibration

2-point
Interpretation

COI >1.0 = non-reactive
COI ≤1.0 = reactive
Traceability

Anti-HBc reference material WHO standard (NIBSC code 95/522)
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.
Sample volume

40 μL cobas e 411 analyzer, cobas e 601 / cobas e 602 modules
24 μL cobas e 801 module
Intermediate precision in positive samples

cobas e 411 analyzer: CV 3.9 – 8.0 %
cobas e 601 / cobas e 602 modules CV 4.9 – 7.3 %
cobas e 801 module CV 2.5 – 4.2 %
Clinical sensitivity

100 % (n = 793 samples from HBV infected patients in different stages of the disease)
Analytical sensitivity

≤0.8 WHO IU/mL
Clinical specificity

100 % (n = 997; diagnostic routine / hospitalized patients)
99.93 % (n = 8,163; blood donors – serum)
99.88 % (n = 9,162; blood donors – plasma)
99.31 % (n = 779; dialysis patients)
100 % (n = 1,000; pregnant women)

Seeger, C., Zoulim, F., Mason, W.S. (2007). Hepadnaviruses. In: Field’s Virology, Knipe DM, Howley RM (eds), 5th edition, Lippincott Williams and Wilkins, Philadelphia, USA. Chapter 76, 2977-3029.
Liang, T.J. (2009). Hepatitis B: the virus and disease. Hepatology 49(5 Suppl), 13-21.
Krajden, M., McNabb, G., Petric, M. (2005). The laboratory diagnosis of hepatitis B virus. Can J Infect Dis Med Microbiol. 16(2), 65-72.
Centers for Disease Control and Prevention (CDC). Interpretation of Hepatitis B Serologic Test Results. Available at: https://www.cdc.gov/hepatitis/hbv/pdfs/serologicchartv8.pdf (accessed April 2020)
Liaw, Y.F., Chu, C.M. (2009). Hepatitis B virus infection. Lancet 373, 582-592.
lgouhari, H.M., Abu-Rajab, Tamini, T.I., Carey, W. (2008). Hepatitis B virus infection: understanding its epidemiology, course, and diagnosis. Cleve Clin J Med. 75, 881-889.
Caspari, G., Gerlick, W.H. (2007). The serologic markers of hepatitis B virus infection – proper selection and standardized interpretation. Clin Lab. 53, 335-343.
WHO. Hepatitis B Fact sheet. Available at: https://www.who.int/en/news-room/fact-sheets/details/hepatitis-b (accessed April 2020).
Pondé, R.A., Cardoso, D.D., Ferro, M.O. (2010). The underlying mechanisms for the ‘anti-HBc alone’ serological profile. Arch Virol. 155, 149-158.
Elecsys^® Anti-HBc II Package Inserts Material numbers 07026790190, 07374160190, 07394764190