Current research and challenges of low-level viremia in patients with chronic hepatitis B

Abstract

Although newborns are generally vaccinated against chronic hepatitis B virus, incidence of HBV infection decreases. However, in 2016, there were still 86 million cases of chronic HBV infection in China. In 2019, there were 296 million cases of chronic HBV infection worldwide, and approximately 820 000 people die from related diseases caused by HBV infection annually, such as liver failure, cirrhosis or HCC. Mostly, the clinical treatment of patients with chronic hepatitis B can achieve therapeutic effects of inhibiting virus replication and delaying disease progression after standar-dized antiviral treatments (such as entecavir, tenofovir, and propofol tenofovir). But with a deeper understanding of the di-sease and the improvement of detection technology, it has been found in clinical practice that some patients, after 48 weeks of standardized treatment, had serum HBV DNA levels below 2 000 IU/mL and continuously or intermittently exceeding the lower limit of detection， which indicates a state of low-level viremia（LLV）. The mechanism of LLV is currently unclear. Related studies have shown that LLV of HBV affects the clinical prognosis of patients, mainly manifesting as promoting liver inflammation, development of liver fibrosis, and an increased risk of decompensated cirrhosis, hepatocellular carcinoma, and drug resistance. In addition, there are no clear recommendations for the treatment of patients with HBV LLV. This article will review the definition, possible mechanisms, clinical significance, and clinical management strategies of HBV LLV, providing reference for clinical physicians.

Keywords

• |hepatitis b virus infection|low level viremia|nucleos(t)ide analogues