Multicentre evaluation of the Elecsys® hepatitis B surface antigen II assay for detection of HBsAg in comparison with other commercially available assays

Seroprevalence of hepatitis B virus and hepatitis C virus infection among Malaysian population

Malaysia is a country with an intermediate endemicity for hepatitis B. As the country moves toward hepatitis B and C elimination, population-based estimates are necessary to understand the burden of hepatitis B and C for evidence-based policy-making. Hence, this study aims to estimate the prevalence of hepatitis B and C in Malaysia. A total of 1458 participants were randomly selected from The Malaysian Cohort (TMC) aged 35 to 70 years between 2006 and 2012. All blood samples were tested for hepatitis B and C markers including hepatitis B surface antigen (HBsAg), anti-hepatitis B core antibody (anti-HBc), antibodies against hepatitis C virus (anti-HCV). Those reactive for hepatitis C were further tested for HCV RNA genotyping. The sociodemographic characteristics and comorbidities were used to evaluate their associated risk factors. Descriptive analysis and multivariable analysis were done using Stata 14. From the samples tested, 4% were positive for HBsAg (95% CI 2.7-4.7), 20% were positive for anti-HBc (95% CI 17.6-21.9) and 0.3% were positive for anti-HCV (95% CI 0.1-0.7). Two of the five participants who were reactive for anti-HCV had the HCV genotype 1a and 3a. The seroprevalence of HBV and HCV infection in Malaysia is low and intermediate, respectively. This population-based study could facilitate the planning and evaluation of the hepatitis B and C control program in Malaysia.

Pretreatment HBsAg level and an early decrease in MELD score predict prognosis to lamivudine treatment for HBeAg-negative acute-on-chronic liver failure

BACKGROUND AND OBJECTIVE

Few data are available about the predictability of HBsAg quantification to nucleos(t)ide analogues treatment in acute-on-chronic liver failure (ACLF). The aim of this study was to investigate HBsAg level combined with the model for end-stage liver disease (MELD) score for predicting prognosis to lamivudine monotherapy in HBeAg-negative ACLF.

METHODS

Fifty-seven nucleoside-naïve patients with HBeAg-negative ACLF were treated with 100mg of lamivudine daily. Serum levels of HBsAg, HBV DNA and biochemical items were detected at baseline, before death (patients died within 3months) or month 3 meanwhile MELD score was calculated. Dynamic of these items and 3-month mortality were analyzed.

RESULTS

HBV DNA level significantly decreased while HBsAg level did not after treatment. Twenty-six patients died within 3months and the others survived. Regardless pre- or post-treatment, HBsAg level of survival group was significantly higher than that of dead group meanwhile MELD scores of the former were significantly lower than those of the latter (all P<0.05). Post-treatment MELD scores of 32 patients with pretreatment HBsAg levels above 4000 COI were significantly lower than those of 25 patients below to it (t=-2.116, P=0.044) and the 3-month mortality of the formers was significantly lower than that of the latter (34.3% [11/32] vs 64.0% [16/25], χ(2)=4.941, P=0.026).

CONCLUSIONS

In HBeAg-negative ACLF, patient with higher pretreatment HBsAg levels and early decrease in MELD score has lower 3-month mortality than one without it during lamivudine monotherapy.

Introduction of an automated system for the diagnosis and quantification of hepatitis B and hepatitis C viruses

Hepatitis B virus (HBV) and Hepatitis C virus (HCV) infections pose major public health problems because of their prevalence worldwide. Consequently, screening for these infections is an important part of routine laboratory activity. Serological and molecular markers are key elements in diagnosis, prognosis and treatment monitoring for HBV and HCV infections. Today, automated chemiluminescence immunoassay (CLIA) analyzers are widely used for virological diagnosis, particularly in high-volume clinical laboratories. Molecular biology techniques are routinely used to detect and quantify viral genomes as well as to analyze their sequence; in order to determine their genotype and detect resistance to antiviral drugs. Real-time PCR, which provides high sensitivity and a broad dynamic range, has gradually replaced other signal and target amplification technologies for the quantification and detection of nucleic acid. The next-generation DNA sequencing techniques are still restricted to research laboratories.The serological and molecular marker methods available for HBV and HCV are discussed in this article, along with their utility and limitations for use in Chronic Hepatitis B (CHB) diagnosis and monitoring.

HBsAg variants: diagnostic-escape and diagnostic dilemma

A wide variety of commercial assays is available for the detection of hepatitis B surface antigen (HBsAg). Clearly, the sensitivity of an assay to detect a variant is dependent on the anti-HBs usage. Thus, it is not surprising that there are examples of variants that cannot be detected by all assays. Data from Europe, Asia and Africa about HBsAg variants which are not recognized by either monoclonal or polyclonal antibodies specific for wild-type group 'a' determinant, but positive by DNA polymerase chain reaction (PCR) in chronic patients and from vaccinated children are increasing. This would impose a challenge for public health issues of hepatitis B virus. In this review we tried to summarize the discrepancies between results of HBsAg assays and to explain some rationales for these inconsistencies.