Although safe and effective vaccines for hepatitis B virus (HBV) have been available for nearly three decades, this virus kills at least 600,000 people annually worldwide and remains the leading global cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Because the HBV reverse transcriptase lacks a proofreading function, many HBV genotypes, subgenotypes, mutants, and recombinants exist. At least 10 HBV genotypes (HBV-A through J) with distinct geographic distributions have been identified; by definition, their complete genomic sequences diverge by more than 8%. HBV genotype is increasingly becoming recognized as an important factor in the progression and clinical outcome of HBV-induced disease. Infections by HBV-C or -D are significantly more likely to lead to cirrhosis and hepatocellular carcinoma than are infections by HBV-A or -B. Additionally, the hepatitis B e antigen seroconversion response to standard or pegylated interferon is more favorable in patients with HBV-A or -B than in those with HBV-C or -D. However, therapeutic responses to nucleos(t)ide analogues are generally comparable among HBV genotypes. In conclusion, genotyping of HBV is useful in identifying chronic hepatitis B patients who are at increased risk of disease progression, thereby enabling physicians to optimize antiviral therapy for these patients.
Antiviral Agents/therapeutic use ; Drug Resistance, Viral/genetics ; Genotype ; Hepatitis B/diagnosis/drug therapy/*epidemiology ; Hepatitis B virus/drug effects/*genetics/pathogenicity ; Humans ; Molecular Epidemiology ; Phenotype ; Prognosis

Hepatitis B virus (HBV) infection is the one of the most common causes of the liver diseases in Korea. Since the discovery of Australia antigen (hepatitis associated antigen, or HBsAg later), hepatitis associated antigen was tested widely. HBsAg was detected in 6.6~8.6% in 1980's. Later, it decreased to 5.7% in 1990's. Remarkably, seropositivity of the children deceased to 0.2% after the nationwide vaccination program. Although hepatitis B vaccines are highly effective, the failure rate of perinatal prophylaxis in babies born to HBsAg positive mother was reported to be 4.25%. Treatment of chronic hepatitis B was initiated after the introduction of interferon alpha. Lamivudine opened a new era of oral antiviral agent, and it has been widely used in Korea since 1999. Adefovir was proven to have a good efficacy for lamivudine-resistant chronic hepatitis B. Newer potent antiviral agents such as entecavir, clevudine, and telbivudine are available currently. Further studies are warranted for understanding factors influencing natural history, improving treatment outcomes, and overcoming vaccine non-response.
Acute Disease ; Antiviral Agents/therapeutic use ; Hepatitis B/diagnosis/drug therapy/*epidemiology/prevention & control ; Hepatitis B Surface Antigens/analysis ; Hepatitis B Vaccines/administration & dosage ; Hepatitis B, Chronic/epidemiology ; Humans ; Immunization Programs ; Korea/epidemiology ; Seroepidemiologic Studies

BACKGROUND/AIMS: Liver dysfunction and reactivation of hepatitis virus are well-described complications in cancer patients who receive cytotoxic chemotherapy and may result in varying degrees of liver damage. However, there has been just few reports on such complications and on the preemptive use of lamivudine in Korea. The aims of this study were to determine the prevalence of hepatitis B and C virus infection and the incidence of liver dysfunction in patients with malignancies who receive chemotherapy, to determine the reactivation rate of hepatitis B virus (HBV) in those patients, to evaluate the effect of preemptive use of lamivudine in patients with HBV infection. METHODS: Among 1,477 patients who received chemotherapy due to various malignancies from January 2000 to June 2005, 668 patients with incomplete viral studies or hepatitis related malignancy were excluded. A retrospective study was conducted by reviewing the medical records of remaining 809 patients. RESULTS: The overall prevalence rate of hepatitis B or C virus in patients receiving chemotherapy was 6.55% (53/809). The incidences of liver dysfunction was not significantly different between hepatitis virus positive group and negative group. Reactivation rate of hepatiris B or C virus after chemotherapy was 15% (6/40). In all patients who received lamivudine therapy, aspartate aminotransferase and alanine aminotransferase level were normalized and HBV DNA negativity achieved. CONCLUSIONS: The existence of hepatitis virus in patients receiving chemotherapy did not significantly influence the development of severe liver dysfunction, owing probably to the lamivudine therapy. Further prospective studies are required to ascertain the reactivation of hepatitis virus in patients receiving chemotherapy and the need for prophylactic lamivudine therapy in HBV positive patients.
Adult ; Antineoplastic Agents/*adverse effects ; Antiviral Agents/*therapeutic use ; Female ; Hepatitis B/diagnosis/epidemiology/*prevention & control ; Hepatitis C/diagnosis/epidemiology/*prevention & control ; Humans ; Lamivudine/*therapeutic use ; Liver Diseases/chemically induced/*diagnosis/epidemiology ; Male ; Middle Aged ; Neoplasms/complications/drug therapy ; Prevalence

Chronic liver disease represents a major public health problem, accounting for significant morbidity and mortality worldwide. As prognosis and management depend mainly on the amount and progression of liver fibrosis, accurate quantification of liver fibrosis is essential for therapeutic decision-making and follow-up of chronic liver diseases. Even though liver biopsy is the gold standard for evaluation of liver fibrosis, non-invasive methods that could substitute for invasive procedures have been investigated during past decades. Transient elastography (TE, FibroScan(R)) is a novel non-invasive method for assessment of liver fibrosis with chronic liver disease. TE can be performed in the outpatient clinic with immediate results and excellent reproducibility. Its diagnostic accuracy for assessment of liver fibrosis has been demonstrated in patients with chronic viral hepatitis; as a result, unnecessary liver biopsy could be avoided in some patients. Moreover, due to its excellent patient acceptance, TE could be used for monitoring disease progression or predicting development of liver-related complications. This review aims at discussing the usefulness of TE in clinical practice.
Antiviral Agents/therapeutic use ; Carcinoma, Hepatocellular/epidemiology/physiopathology ; Chronic Disease ; *Elasticity Imaging Techniques ; Hepatitis B/drug therapy/physiopathology ; Hepatitis C/drug therapy/physiopathology ; Humans ; Liver Cirrhosis/*diagnosis/ultrasonography ; Liver Neoplasms/epidemiology/physiopathology ; Recurrence

BACKGROUND/AIMS: Lamivudine (LAM) plus adefovir (ADV) combination therapy has been accepted as one of the best treatments for LAM-resistant chronic hepatitis B (CHB). The aim of this study was to determine the efficacy of this combination therapy in hepatocellular carcinoma (HCC) patients. METHODS: The medical records of CHB patients who developed LAM resistance and were treated with LAM plus ADV combination therapy for more than 6 months were reviewed. Their virological response (VR; undetectable HBV DNA) and biochemical response (BR; alanine aminotransferase normalization) were evaluated, and the findings of HCC and non-HCC patients were compared. RESULTS: The data from 104 patients (19 with HCC and 85 without HCC) were analyzed. The VR rates did not differ significantly between the HCC and non-HCC groups: 33.3% vs. 55.6% at 12 months (P=0.119), 58.3% vs. 67.2% at 24 months (P=0.742), 50% vs. 69.8% at 36 months (P=0.280), and 66.7% vs. 71.0% at 48 months (P=1.000). The BR rates also did not differ significantly between the groups: 55.6% vs. 84.0% at 12 months (P=0.021), 58.3% vs. 83.8% at 24 months (P=0.057), 70.0% vs. 77.8% at 36 months (P=0.687), and 66.7% vs. 80.6% at 48 months (P=0.591). CONCLUSIONS: The efficacy of LAM plus ADV combination therapy is comparable in HCC and non-HCC patients.
Adenine/*analogs & derivatives/therapeutic use ; Adult ; Antiviral Agents/*therapeutic use ; Carcinoma, Hepatocellular/*diagnosis/epidemiology/etiology ; DNA, Viral/analysis ; Drug Administration Schedule ; Drug Resistance, Viral ; Drug Therapy, Combination ; Genotype ; Hepatitis B virus/genetics ; Hepatitis B, Chronic/*drug therapy/virology ; Humans ; Incidence ; Lamivudine/*therapeutic use ; Liver Cirrhosis/diagnosis/epidemiology/etiology ; Liver Neoplasms/*diagnosis/epidemiology/etiology ; Middle Aged ; Organophosphonates/*therapeutic use ; Retrospective Studies ; Treatment Outcome

BACKGROUND/AIMS: The incidence of Hepatitis B has significantly declined since the introduction of an HBV vaccination program. The aim of this study was to investigate recent clinical features of acute viral hepatitis B (AVH-B) in Korea. METHODS: A total of 2241 patients with acute viral hepatitis were enrolled and their data were collected from nine medical-centers between January 2006 and December 2009. RESULTS: One hundred nineteen (5.3%) of the 2241 were diagnosed as AVH-B. Among 78 patients with AVH-B whose data were analyzed, 50 were male, and the mean age was 38.6 years. In an initial test, mean AST, ALT and total-bilirubin levels were 1296.2 IU/L, 2109.6 IU/L and 9.3 mg/dl, respectively. Positivity frequencies for HBeAg and anti-HBe were 55.1% and 67.9%, respectively, and the mean HBV DNA level was 5.2 log10 copies/ml. The mean length of hospitalization was 11.6 days. During follow-up, AST, ALT and total bilirubin levels were normalized or near-normalized in all patients without serious complications. Sixty-three of 66 (95.4%) patients showed HBsAg loss and 37 (56.1%) patients showed HBsAg seroconversion. Only 3 patients (4.5%) showed persistent hepatitis B viremia. There was no case of death or liver transplantation. Nine patients (11.3%) had received anti-viral agents and their clinical outcomes were not significantly different from those of patients treated without antiviral agents. CONCLUSIONS: The prevalence of AVH-B among acute hepatitis patients is relatively low in Korea. AVH-B infection can be cured without complications in almost all patients, regardless of antiviral treatment.
Acute Disease ; Adult ; Alanine Transaminase/blood ; Antiviral Agents/therapeutic use ; Aspartate Aminotransferases/blood ; Bilirubin/blood ; DNA, Viral/analysis ; Female ; Hepatitis B/*diagnosis/drug therapy/epidemiology ; Hepatitis B Antibodies/blood ; Hepatitis B e Antigens/blood/immunology ; Humans ; Male ; Middle Aged ; Retrospective Studies