Cập nhật điều trị viêm gan B

Editor's Notes

• #14: ALT, alanine aminotransferase; HBeAg, hepatitis B e antigen.   The hepatitis B patient population comprises 2 distinct groups with differing goals of therapy. Among patients with wild-type virus, that is, HBeAg-positive patients, the loss of e antigen with seroconversion to e antibody is an important treatment endpoint. This goal is achieved through suppression of HBV DNA and is frequently associated with ALT normalization.   The HBeAg-negative population, which consists of patients with both precore and core promoter mutations, is a more difficult population to treat. HBeAg seroconversion is obviously not an endpoint in these patients. Instead, the aim is to achieve durable suppression of HBV DNA, which should, in turn, result in ALT normalization. Because no serological endpoint exists, treatment in this group of patients may take much longer than in patients who have wild-type hepatitis B.
• #15: AASLD; American Association for the Study of Liver Diseases; ALT, alanine aminotransferase; APASL, Asian Pacific Association for the Study of the Liver; EASL, European Association for the Study of the Liver; HBeAg, hepatitis B e antigen; HBV, hepatitis B virus; NIH, National Institutes of Health; ULN, upper limit of normal.   We will now discuss how to use these tools to determine treatment candidacy. Several guidelines are available to help guide this decision. The American Association for the Study of Liver Diseases (AASLD) guidelines are used commonly in the United States, but many clinicians also look to the European Association for the Study of the Liver guidelines, the Asian Pacific Association for the Study of the Liver guidelines, or the statement from the National Institutes of Health. Each guideline uses similar principles to determine candidacy, with some slight differences, as shown in this table.   For simplicity, we will focus on the AASLD guidelines. This table is split into HBeAg-positive and HBeAg-negative disease. Among HBeAg-positive individuals, the key cutoffs for determining treatment candidacy are an HBV DNA level of 20,000 IU/mL and an ALT of more than 2 times the upper limit of normal or moderate to severe inflammation or significant fibrosis by biopsy.   Among HBeAg-negative individuals, the factors for determining treatment candidacy are essentially the same when the AASLD guidelines are used.  
• #34: HBV, hepatitis B virus.   The hepatitis B treatment landscape is changing. In the early 1990s, the only treatment available for HBV was interferon alfa-2b. This agent was given for a short period, and only a few patients responded to treatment. In 1998, the first oral nucleoside analogue, lamivudine, was introduced, followed fairly rapidly by the nucleotide analogue adefovir. Standard interferon alfa-2b was then replaced by peginterferon alfa-2a, which was administered via once-weekly injections as opposed to daily treatment. Other nucleoside and nucleotide analogues, that is, entecavir, telbivudine, and tenofovir, soon followed.
• #36: What are the current recommendations for first-line therapy? Two oral antivirals and 1 injectable agent are recommended as first-line options by major liver disease societies. Both entecavir and tenofovir can be used safely in nearly all HBV-infected patients, whereas peginterferon alfa-2a should not be used in patients who are pregnant or who have decompensated liver cirrhosis and should not be used as prophylaxis against HBV reactivation (eg, in patients undergoing chemotherapy) or in the setting of acute infection.