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Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Worldwide, chronic hepatitis B virus (HBV) infection is the primary cause of cirrhosis and hepatocellular carcinoma and is one of the ten leading causes of death. Traditionally, people with chronic HBV infection have been identified with blood tests for HBV antigens and antibodies. Recently, another group of patients with chronic HBV infection has been identified by sensitive, molecular testing for HBV DNA. Members of this group are often referred to as having occult hepatitis B because they are HBV-DNA positive, but hepatitis B surface antigen negative. Occult hepatitis B occurs in a number of clinical settings. In this review, we examine occult hepatitis B in people co-infected with hepatitis C, in whom occult hepatitis B has been associated with advanced fibrosis and diminished response to interferon alpha. Although much more research is needed, existing reports justify a heightened awareness of the medical importance and means of testing for occult hepatitis B.
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PMID:Occult hepatitis B. 1215 Aug 47

Hepatitis B virus (HBV) causes a generally non-cytopathic infection in the liver. Even though HBV is a DNA virus, it replicates via reverse transcription which is coordinated within the viral nucleocapsid by the virus-specific polymerase. The major transcriptional template is the viral mimichromosome from which the viral DNA exists as a covalently closed circular (ccc) molcule. The virus infects hepatocytes but can also be found in non-hepatocyte reservoirs such as bile-duct epithelium, mesangial cells of the kidney, pancreatic islet cells and lymphoid cells. When patients infected with HBV are treated with either interferon alpha or lamivudine, responses are variable and unpredictable. Sophisticated mathematical models analysing the dynamics of viral clearance during antiviral therapy have recently been applied to chronic hepatitis B. Typically complex profiles, rather than the usual biphasic responses seen with other diseases have been observed, indicating that antiviral efficacy requires substantila improvement. This may be achieved with combination chemotherapy. However, chronic hepatitis B is a complex and heterogeneous disease entity, and the challenge for the future is to define measurable end-points of treatment and address key virological issues such as the role of cccDNA and extra-hepatocyte replication in treatment failure. Clearly, new therapies and effective combination therapy protocols are urgently required in order to improve the present poor response rates in patients undergoing treatment.
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PMID:Hepatitis B treatment: rational combination chemotherapy based on viral kinetic and animal model studies. 1220 77

Chronic hepatitis B virus (HBV) infection affects approximately 350 million people worldwide. Treatment of chronic hepatitis B is aimed at sustained suppression of HBV replication and remission of liver disease. Currently, antiviral treatment is indicated for hepatitis B e antigen (HBeAg)-positive patients in the immune clearance phase, and for HBeAg-negative patients with evidence of active liver disease and continued high levels of HBV replication. Treatment is not recommended for patients in the immune tolerance phase or the inactive carrier state, due to lack of efficacy of current treatment. This review updates safety and efficacy data of interferon alpha and lamivudine in the treatment of chronic hepatitis B. Management strategies in different clinical scenarios and future treatments are also discussed.
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PMID:Treatment of hepatitis B. 1242 59

Hepatitis B e antibody (HbeAb) and hepatitis B virus (HBV) DNA positive chronic hepatitis is a clinical entity, distinct from classical hepatitis B e antigen (HbeAg) positive chronic hepatitis B. Our aim was to evaluate the long-term therapeutic efficacy of the combination of interferon alpha-2b and thymosin-alpha1 compared with lamivudine plus interferon alpha-2b and interferon alpha-2b alone. Fifty-two patients with HbeAg-negative chronic hepatitis B were assigned to three different groups in a nonrandomized manner. Group 1 (n = 27) received thymosin-alpha1 [1.6 mg subcutaneously (sc), twice a week] and interferon alpha-2b (10 MIU sc, three times per week) for 26 weeks, subsequently followed by interferon alpha-2b monotherapy at the same dosage for an additional 26 weeks. Group 2 (n = 10) received interferon alpha-2b (10 MIU sc, three times per week) for 52 weeks. Group 3 (n = 15) received interferon alpha-2b (10 MIU sc, three times per week) and lamivudine [100 mg orally (po), q.d.] for 52 weeks, followed by continuous lamivudine (100 mg po, q.d.) therapy. By the end of 78 weeks, a sustained response (SR-6 mo) was seen in 74% (20/27) of the patients within Group 1. On the contrary, Groups 2 and 3 had sustained response rates of 40 (4/10) and 53.3% (8/15), respectively (p = 0.13). At the end of 12 months post-treatment in Group 1, a virological and biochemical response rate was seen in 70.3% of patients (19/27); in contrast, Groups 2 and 3 had response rates of 20 (2/10) and 26.6% (4/15), respectively (p = 0036). At the end of the 18-month post-treatment follow-up period, 71.4% (19/27) of patients in Group 1, 10% of patients in Group 2 (1/10), and 20% of patients in Group 3(3/15) preserved their sustained response (p = 0.0003). Interferon alpha-2b and thymosin-alpha1 combination therapy results in significant virological and biochemical response rates compared with standard therapeutic regimens and is well tolerated.
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PMID:Long-term outcomes of thymosin-alpha 1 and interferon alpha-2b combination therapy in patients with hepatitis B e antigen (HBeAg) negative chronic hepatitis B. 1282 Jan 43

Current therapies for chronic hepatitis B (CHB) have a number of limitations, and better treatment options are needed. Peginterferon alpha-2a (40 kDa) is superior to conventional interferon alpha-2a in the treatment of chronic hepatitis C. This is the first report on peginterferon alpha-2a (40 kDa) in the treatment of CHB. In this phase II study, 194 patients with CHB not previously treated with conventional interferon-alpha were randomized to receive weekly subcutaneous doses of peginterferon alpha-2a (40 kDa) 90, 180 or 270 microg, or conventional interferon alpha-2a 4.5 MIU three times weekly. Twenty-four weeks of therapy were followed by 24 weeks of treatment-free follow-up. All subjects were assessed for loss of hepatitis B e antigen (HBeAg), presence of hepatitis B antibody (anti-HBe), suppression of hepatitis B virus (HBV) DNA, and normalization of serum alanine transaminase (ALT) after follow-up. At the end of follow-up, HBeAg was cleared in 37, 35 and 29% of patients receiving peginterferon alpha-2a (40 kDa) 90, 180 and 270 microg, respectively, compared with 25% of patients on conventional interferon alpha-2a. The combined response (HBeAg loss, HBV DNA suppression, and ALT normalization) of all peginterferon alpha-2a (40 kDa) doses combined was twice that achieved with conventional interferon alpha-2a (24%vs 12%; P = 0.036). All treatment groups were similar with respect to frequency and severity of adverse events. These results indicate that peginterferon alpha-2a (40 kDa) is superior in efficacy to conventional interferon alpha-2a in chronic hepatitis B based on clearance of HBeAg, suppression of HBV DNA, and normalization of ALT.
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PMID:Peginterferon alpha-2a (40 kDa): an advance in the treatment of hepatitis B e antigen-positive chronic hepatitis B. 1282 97

Chronic hepatitis B virus (HBV) infection is a well-recognized risk factor for the development of hepatocellular carcinoma (HCC), which is becoming a more prevalent clinical problem, especially in HBV-endemic areas. It is estimated that 1.25 million people in the United States and more than 300 million people worldwide are chronically infected with HBV. Despite the introduction of universal vaccination against hepatitis B in over 100 countries, persistent HBV infection is still a serious problem worldwide, causing an estimated annual death rate of one million. It may take several decades until the effect of vaccination will be translated into reduced transmission and morbidity. Meanwhile, patients with persistent HBV infection require better antiviral therapeutic modalities than are currently available. It is well accepted that antiviral therapy for chronic hepatitis B is effective to improve prognosis of patients with HBV by preventing development of hepatitis state and HCC. The therapeutic endpoints for hepatitis B treatment are: 1) sustained suppression of HBV replication, as indicated by HBsAg and HBeAg loss, 2) decrease of serum HBV DNA of an undetectable level by a non-PCR method, 3) remission of disease, as shown by normalization of ALT, 4) improvement in liver histology, and 5) reduction of the acute exacerbation, cirrhosis, and HCC. In the present, the antiviral treatment of hepatitis B consists of either interferon alpha or oral lamivudine alone or in combination with existing therapy. Each major antiviral drug of interferon alpha and lamivudine has pros and cons, and effect of combination therapy of both drugs is also still limited. More powerful and safe new antiviral therapies are required to achieve final goal of these therapeutic endpoints. Management of chronic hepatitis B requires significant knowledge of approved pharmacotherapeutic agents and their limitations. Therapeutic options for managing hepatitis infection after liver transplantation (LT) are also evolving.
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PMID:Antiviral therapy for chronic hepatitis B: a review. 1503 42

Studies of 4 to 6 months of treatment with interferon for hepatitis B e antigen (HBeAg)-positive chronic hepatitis B virus (HBV) infection have shown clearance of HBeAg to be higher in treated patients than it is in controls by approximately 25%. These results are considerably better than those with antiviral agents. Therefore, the recent European Association for the Study of the Liver (EASL) Consensus Committee recommended the use of interferon alpha for this condition. Treatment with pegylated interferons in several trials has shown better results still. Lamivudine in combination with interferon, however, did not improve the results at 6 months after the end of therapy. In HBeAg-negative chronic HBV infection, pegylated interferon alpha is superior to lamivudine, and, again, combination with lamivudine does not improve the results. Side effects in all studies have been tolerable. Thus, these observations in chronic HBV infection, whether HBeAg-positive or HBeAg-negative, suggest an important, even primary, role for pegylated interferon therapy.
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PMID:Treatment with interferons (including pegylated interferons) in patients with hepatitis B. 1519 1

Dendritic cells (DC) play an important role in the induction of T-cell responses. We hypothesize that the hampered antiviral T-cell response in chronic hepatitis B patients is a result of impaired dendritic cell function. In this study, we compared the number, phenotype and functionality of two important blood precursor DC, myeloid DC (mDC) and plasmacytoid DC (pDC), of chronic hepatitis B patients with healthy volunteers. No differences in percentages of mDC and pDC in peripheral blood mononuclear cells were observed between chronic hepatitis B patients and healthy controls. The allostimulatory capacity of isolated and in vitro matured mDC, but not of pDC, was significantly decreased in patients compared to controls. Accordingly, a decreased percentage of mDC expressing CD80 and CD86 was observed after maturation, compared to controls. In addition, mDC of patients showed a reduced capacity to produce tumor necrosis factor alpha after a stimulus with synthetic double-stranded RNA and interferon gamma. Purified pDC from patients produced less interferon alpha, an important antiviral cytokine, in response to stimulation with Staphylococcus aureus Cowan strain I than pDC isolated from controls. In conclusion, mDC and pDC are functionally impaired in patients with chronic hepatitis B. This might be an important way by which hepatitis B virus evades an adequate immune response, leading to viral persistence and disease chronicity.
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PMID:Functional impairment of myeloid and plasmacytoid dendritic cells of patients with chronic hepatitis B. 1534 14

Hepatitis B virus (HBV) superinfection in chronic hepatitis C represents a natural model to investigate whether or not hepatitis C virus (HCV) can influence priming and maturation of antiviral T cells; whether or not HBV superinfection, which is known to determine control of HCV replication, can restore HCV-specific T cell responsiveness; and whether or not cytokines stimulated by HBV infection can contribute to HCV control. To address these issues, the function of CD8 cells specific for HBV and HCV was studied longitudinally in two chronic HCV patients superinfected with HBV. Patients with acute hepatitis B were also examined. Frequency and function of HBV tetramer+ CD8 cells were comparable in patients acutely infected with HBV with or without chronic HCV infection. HBV-specific CD8 cell function was efficiently expressed irrespective of serum HCV-RNA levels. Moreover, fluctuations of HCV viremia at the time of HBV superinfection were not associated with evident changes of CD8 responsiveness to HCV. Finally, no correlation was found between serum levels of interferon alpha, interleukin (IL)-12, IL-10, or IL-18 and control of HCV replication. In conclusion, HCV did not affect the induction of primary and memory HBV-specific CD8 responses. HCV-specific CD8 responses were undetectable when HCV-RNA was negative, showing that inhibition of HCV replication in the setting of a HBV superinfection was not sufficient to induce a restoration of CD8 reactivity against HCV.
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PMID:Antiviral CD8-mediated responses in chronic HCV carriers with HBV superinfection. 1536 33

Infection by the hepatitis B virus (HBV) is a significant cause of morbidity and mortality, mainly due to evolvement to cirrhosis and hepatocellular carcinoma. The prevalence and genotypic distribution of HBV infection has marked geographic differences. HBV infection is a very dynamic process, with a phase of immune tolerance and high viral replication, followed by HBeAg clearance, not always accompanied by complete suppression of HBV replication. The latter situation corresponds to negative HBeAg hepatitis, which represents a group relatively resistant to therapy. The three approved drugs for the treatment of HBV infection (interferon alpha, lamivudine and adefovir) have limited efficacy. Relapses are more common with lamivudine and adefovir, requiring often long-term treatment. While the selection of lamivudine resistance mutations is frequent, adefovir has a high genetic barrier. HIV infection negatively impacts on HBV disease, requiring these coinfected patients strategies aimed to manage both viruses.
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PMID:[Advances in the diagnosis and treatment of the infection by the hepatitis B virus]. 1551 95


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