Performance of HBsAg point-of-care tests for detection of diagnostic escape-variants in clinical samples

Point-of-Care Testing for Hepatitis Viruses: A Growing Need

Viral hepatitis, caused by hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV), or hepatitis E virus (HEV), is a major global public health problem. These viruses cause millions of infections each year, and chronic infections with HBV, HCV, or HDV can lead to severe liver complications; however, they are underdiagnosed. Achieving the World Health Organization's viral hepatitis elimination goals by 2030 will require access to simpler, faster, and less expensive diagnostics. The development and implementation of point-of-care (POC) testing methods that can be performed outside of a laboratory for the diagnosis of viral hepatitis infections is a promising approach to facilitate and expedite WHO's elimination targets. While a few markers of viral hepatitis are already available in POC formats, tests for additional markers or using novel technologies need to be developed and validated for clinical use. Potential methods and uses for the POC testing of antibodies, antigens, and nucleic acids that relate to the diagnosis, monitoring, or surveillance of viral hepatitis infections are discussed here. Unmet needs and areas where additional research is needed are also described.

Detection of S-HBsAg Mutations in Patients with Hematologic Malignancies

Multiple studies of hepatitis B virus (HBV) genetic variability and its relationship with the disease pathogenesis are currently ongoing, stemming from growing evidence of the clinical significance of HBV mutations. It is becoming increasingly evident that patients with hematologic malignancies may be particularly prone to a higher frequency of such mutations. The present report is the first extensive study of the prevalence of escape mutations in S-HBsAg, performed using isolates from 59 patients from hospital hematology departments with diagnoses of leukemia (n = 32), lymphoma (n = 20), multiple myeloma (n = 3), and non-tumor blood diseases (n = 4). The isolates were serologically examined for the presence of HBV markers and sequenced using either next-generation sequencing (NGS) or Sanger sequencing. Occult hepatitis B was found in 5.1% of cases. Genetic analysis of the region corresponding to S-HBsAg demonstrated an exceptionally high mutation frequency in patients with leukemias (93.4%) and lymphomas (85.0%), along with the prominent mutation heterogeneity. Additionally, more than 15 mutations in one sample were found in patients with leukemias (6.3% of cases) and lymphomas (5.0% of cases). Most of the mutations were clinically significant. The study analyzes the mutation profile of HBV in different oncohematological diseases and the frequency of individual mutations. The data strongly suggest that the NGS method, capable of detecting minor populations of HBV mutations, provides a diagnostic advantage, lays the foundation for the development of screening methods, and allows for the study of the virological and pathogenetic aspects of hepatitis B.

The current situation and challenges of screening for and treating hepatitis B in sub-Saharan Africa

Hepatitis B virus (HBV) infection is the most important cause of hepatocellular carcinoma in sub-Saharan Africa (SSA). Although the tools to curb the epidemic are known, only a minority of HBV-infected persons are currently diagnosed and treated. Areas covered: We discuss HBV epidemiological trends in SSA, describe important determinants of its natural history, and summarize current knowledge on the continuum of HBV care. Using the results of a systematic review of the literature, we describe the proportion of patients with liver fibrosis at presentation for care. Throughout the manuscript, we highlight major research gaps and explore potential ways to improve uptake of HBV testing, evaluation of liver disease, access to antiviral therapy and monitoring of complications. Expert commentary: Less than 1% of HBV-infected individuals are diagnosed in SSA, despite the availability of rapid tests with good diagnostic accuracy. Up to 15% of individuals enter care with liver cirrhosis, a clear indication for antiviral therapy. Although the proportion of patients eligible for immediate antiviral treatment is generally below 20%, there are few published data from prospective cohort studies. The incidence of hepatocellular carcinoma could be reduced with improved access to antiviral therapy.