Chronic hepatitis B

Disease Description (Causes and Symptoms)

• Definition: Chronic hepatitis B is a condition in which infection with the hepatitis B virus (HBV) persists for 6 months or longer, causing chronic inflammation and necrosis in the liver.
• Causes/Pathophysiology: When HBV infects liver cells and ongoing viral replication and chronic inflammation persist, the disease may progress to liver fibrosis, cirrhosis, hepatocellular carcinoma (HCC), and other conditions. Routes of infection include blood and bodily fluids (sharing needles, contaminated medical equipment), sexual contact, and vertical transmission (mother-to-child transmission).
• Main symptoms: Most people have no symptoms. Some may experience fatigue, loss of appetite, nausea and vomiting, fever, joint pain, and discomfort in the right upper abdomen. As the disease worsens, jaundice (yellowing of the eyes and skin), dark urine, and itching may develop.
• Key points in diagnosis: Chronic hepatitis B is diagnosed when HBsAg remains positive for 6 months or longer on blood tests. In addition, HBeAg, HBV DNA, AST/ALT, and liver biopsy or noninvasive fibrosis tests are used to assess disease activity and the degree of fibrosis.

Treatment Methods (Standard Treatment, Medication, Procedures/Surgery, Lifestyle Management and Precautions)

• Antiviral treatment
  • Oral antiviral drugs (preferred agents): Drugs with high antiviral efficacy and a low risk of resistance, such as tenofovir and entecavir, are used as first-line treatments.
  • Interferon treatment: Peginterferon (peg‑IFN) is used for limited indications and has an immunomodulatory effect when administered by injection.
  • Indications for treatment: Treatment is generally determined by considering HBV DNA levels, elevated ALT (liver enzyme) levels, liver fibrosis and hepatitis activity, and the presence or absence of cirrhosis. When cirrhosis is present, treatment is often recommended if HBV DNA is detectable.
• Treatment goals and monitoring
  • The goals of treatment are to suppress viral replication (make HBV DNA undetectable or greatly reduce it), suppress hepatitis activity, prevent progression of liver disease, and reduce the risk of HCC.
  • Regular tests during treatment: HBV DNA, AST/ALT, HBsAg/HBeAg, kidney function (particularly when using tenofovir), liver ultrasound and AFP, etc. (For people with cirrhosis or those at high risk, HCC surveillance is performed at 6-month intervals.)
• Lifestyle management and precautions
  • Complete abstinence from alcohol (alcohol worsens liver damage). Use caution with potentially hepatotoxic drugs (including some painkillers and herbal medicines).
  • Weight control, regular exercise, and a balanced diet are recommended.
  • To prevent sexual transmission, condom use and vaccination of partners are recommended.
  • When taking antiviral drugs, take them regularly and undergo regular tests (liver enzyme levels, HBV DNA, kidney function, etc.).
  • If acute worsening occurs (severe jaundice, bleeding, decreased consciousness, etc.), visit an emergency medical institution immediately.
• Prevention (summary)
  • HBV vaccination (checking antibody levels after completing the full vaccination series is recommended).
  • Administration of HBIG (immunoglobulin) and the vaccine within 24 hours after exposure (for exposed people without immunity).
  • If the mother is HBsAg-positive, administer HBIG and the vaccine to the newborn immediately after birth; if the mother’s HBV DNA is high, preventive antiviral treatment may be considered in late pregnancy.

Checklist Before an Outpatient Visit (Including Items to Bring and Example Questions)

• Items to bring/submit
  • A list of all medications, herbal medicines, and health functional foods currently being taken (including dosage and duration of use)
  • Previous test results (HBsAg, HBsAb, HBeAg, HBV DNA, AST/ALT, bilirubin, platelet count, liver ultrasound, liver fibrosis test results, etc.)
  • A record of recent symptoms (fever, fatigue, jaundice, changes in urine color, abdominal pain, etc., including when they began and how they have changed)
  • Medical history, including alcohol and smoking history, major illnesses, surgeries, blood transfusions, and sexual contact history
  • Possibility of pregnancy or current pregnancy (for women)
• Tests that may be performed during the outpatient visit (expected)
  • Blood tests: HBV-related tests (HBsAg/HBeAg/HBsAb), HBV DNA, liver function (AST/ALT/bilirubin), blood coagulation and blood cell counts, and kidney function
  • Imaging: Liver ultrasound (CT/MRI if necessary)
  • Liver fibrosis assessment: Transient elastography (FibroScan) or liver biopsy (if necessary)
• Example questions before an outpatient visit (questions patients can prepare themselves)
  • What do my current HBV status (HBsAg, HBeAg, and HBV DNA level) mean?
  • Is treatment necessary for my condition? If I start treatment, how long will I need to continue it?
  • What are the main side effects of the medication I am currently taking (or planning to take)?

General Example Questions to Ask the Doctor

• What are the expected benefits and possible side effects of this medication (or treatment)?
• What exactly are the criteria for starting treatment, and which tests should I have during treatment and how often?
• Can I expect a cure (loss of HBsAg) with treatment? What are the options if treatment fails or the disease relapses?
• I am planning a pregnancy. What is the safety of the medication, and how should I be managed during pregnancy?
• What is my risk of liver cancer (HCC), and how should I be monitored?

Examples of Disease-Specific Questions (1–2)

• How do my HBeAg status and HBV DNA level currently affect the treatment decision? (For example, HBeAg-positive status with high HBV DNA vs. an HBeAg-negative situation)
• If I already have cirrhosis or liver fibrosis is suspected, what are the criteria for starting treatment, and how should HCC surveillance (the frequency of liver ultrasound and AFP testing) be conducted?

(Note: General recommendation — If cirrhosis is present and HBV DNA is detectable, treatment is recommended; for HCC surveillance, liver ultrasound with or without AFP is generally recommended at 6-month intervals. Individual prescriptions should follow the evaluation of the treating physician.)