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排序方式: 共有1023条查询结果,搜索用时 15 毫秒
91.
Perrillo RP Lai CL Liaw YF Dienstag JL Schiff ER Schalm SW Heathcote EJ Brown NA Atkins M Woessner M Gardner SD 《Hepatology (Baltimore, Md.)》2002,36(1):186-194
Elevated alanine transaminase (ALT) levels and low serum hepatitis B virus (HBV) DNA predict a higher likelihood of hepatitis B e antigen (HBeAg) loss in patients with chronic hepatitis B treated with interferon. Predictors of HBeAg loss in patients treated with lamivudine are not known. The objective of this analysis of 4 lamivudine-controlled Phase III trials was to determine patient-dependent or laboratory variables that predict HBeAg loss. Predictors of HBeAg loss in patients treated with interferon, lamivudine plus interferon, or placebo are also described. A total of 805 adults with chronic hepatitis B were treated either with lamivudine (n = 406), matching placebo (n = 196), interferon (n = 68), or the combination of lamivudine plus interferon (n = 135). Demographic and baseline disease characteristics were used in stepwise multivariate analyses to identify features that were predictive of lamivudine-induced HBeAg loss. HBeAg loss correlated with increased pretreatment ALT levels in all groups. The rate of HBeAg loss was highest among patients with pretreatment ALT levels greater than 5 times the upper limit of normal (ULN) and was most pronounced in the lamivudine group (56%). Multivariate modeling indicated that elevated baseline ALT levels (P <.001) and histologic activity index (HAI) score (P <.001) were important predictors of HBeAg loss in response to lamivudine. The effect of pretreatment ALT levels on HBeAg loss was similar for Asians and Caucasians. In conclusion, elevated pretreatment ALT levels and/or active histologic disease were the most important predictors of lamivudine-induced HBeAg loss. Asians and Caucasians had similar rates of response to lamivudine at comparable ALT levels. 相似文献
92.
Liaw YF 《Journal of viral hepatitis》2002,9(6):393-399
Better understanding of hepatitis B virus (HBV) replication, natural history and the immunopathogenesis of chronic hepatitis B, together with the introduction of effective agents with different mechanisms of action are the basis for better therapeutic strategies against chronic hepatitis B. Among currently available drugs, interferon-alpha and thymosin-alpha1 have only modest efficacy (approximately 40% vs 9-20% in controls). In the past decade, lamivudine has dominated in the treatment of chronic HBV infection because it is easy to use, safe, and is effective in terms of hepatitis B e antigen and/or HBV-DNA loss, ALT normalization, and improvement in histology. The response rate increases with increasing pretherapy alanine aminotransferase (ALT) levels, suggesting that patients with stronger endogenous immune response against HBV have a better response to direct antiviral agents. Lamivudine is also beneficial in decompensated cirrhotics with HBV replication. Hepatitic flares may occur after stopping lamivudine therapy in nonresponders and also in responders. Therefore, prolonged therapy is usually required. However, tyrosine-methionine-aspartate-aspartate (YMDD) mutations conferring resistance to lamivudine start to emerge after 6-9 months of therapy, and hepatitis flare, even decompensation, may develop after viral breakthrough. Thus the benefits of long-term lamivudine therapy must be balanced against the concern about YMDD mutations and the durability of treatment response. Adefovir dipivoxil, entecavir, emtricitabine, clevudine and other nucleoside/ nucleotide analogues have shown encouraging results and some agents appear effective in patients with YMDD mutants. Further development of new drugs and new strategies may help to improve treatment in the new century. 相似文献
93.
94.
HBeAg seroconversion as an important end point in the treatment of chronic hepatitis B 总被引:1,自引:0,他引:1
Yun-Fan Liaw 《Hepatology International》2009,3(3):425-433
During the natural history of chronic hepatitis B virus (HBV) infection, the loss of serum hepatitis B e antigen (HBeAg) and
the development of anti-HBe antibodies (HBeAg seroconversion) mark a transition from the immune-active phase of disease to
the inactive carrier state. This review examines the evidence from natural history and cohort studies on the relationship
between HBeAg seroconversion and disease progression. The role of HBeAg seroconversion as an important milestone in the management
of HBeAg-positive patients with chronic hepatitis B (CHB), as well as the advantages and disadvantages of administering a
finite course of therapy for HBeAg-positive CHB, is also discussed. The evidence from natural history and cohort studies indicates
that spontaneous or treatment-induced HBeAg seroconversion is associated with lower rates of disease progression to cirrhosis
and hepatocellular carcinoma, a potential of hepatitis B surface antigen seroconversion, and improved survival rates. Updated
guidelines developed by major liver associations recommend stopping oral therapy for HBeAg-positive patients who achieve sustained
HBeAg seroconversion with polymerase chain reaction-undetectable HBV-DNA on two separate occasions for 6 or more months apart,
taking into consideration the individual’s clinical and virologic response to therapy, as well as the severity of liver disease.
Thus, early induction of HBeAg seroconversion with interferon-based therapy or oral nucleos(t)ide analogues has important
clinical and socioeconomic implications for the management of CHB. 相似文献
95.
Chia-Ming Chu MD I-Shyan Sheen MD Chau-Ting Yeh MD Sen-Yung Hsieh MD Sun-Lung Tsai MD Yun-Fan Liaw MD 《Digestive diseases and sciences》1995,40(10):2107-2112
To evaluate the potential implication ofin vivo interferon production in the pathogenesis of different forms of acute and chronic hepatitis B virus infection, serum levels of interferon- and- were measured using immunoassay techniques in 20 patients with acute hepatitis B who subsequently cleared the virus (group Ia), 8 patients with acute hepatitis B who became HBsAg carriers (group Ib), 55 patients with chronic hepatitis B (group II), and 15 healthy controls. None of the controls had interferon- or- detectable in serum, while 15% and 100% of group Ia patients, 25% and 100% of group Ib patients, and 22% and 15% of group II patients, had raised serum levels of interferon- and-, respectively. Serum interferon- was detected significantly more frequently in group Ia and Ib patients than in controls and in group II patients. Among patients with acute hepatitis B, serum levels of interferon- and- showed no significant difference between group Ia and group Ib patients. Among patients with chronic hepatitis B, interferon- was detected significantly more frequently in patients with serum HBV-DNA (31.4% or 11/35) than in those without (5% or 1/20), whereas interferon- was detected significantly more frequently in patients with chronic active hepatitis (28% or 7/25) than in those with chronic persistent hepatitis (3.3% or 1/30). In conclusion, in acute hepatitis B, serum levels of interferon- and- did not show a significant difference between patients who subsequently cleared the virus and those who became HBsAg carriers. In chronic hepatitis B, the raised serum levels of interferon- correlated with the presence of viral replication, while the raised serum levels of interferon- correlated with the presence of histological evidence of active hepatitis. 相似文献
96.
Two types of clinical events, acute exacerbation and uneventful course, precede spontaneous HBeAg seroconversion to its antibody (anti-HBe) in chronic type B hepatitis. To examine the possible mechanism responsible for these two types of clinical events, serial serum specimens from 75 patients who underwent spontaneous HBeAg seroconversion were assayed for hepatitis B virus DNA by slot blot hybridization with 32P-labeled cloned hepatitis B virus DNA as probe. Of these 75 patients, 47 (62.7%) had episodes of acute exacerbation (ALT greater than 300 IU per liter) within 3 months prior to HBeAg seroconversion. All of these 47 patients had high hepatitis B virus DNA levels (greater than 1,000 pg per ml) at the onset of acute exacerbation. Their serum hepatitis B virus DNA disappears shortly before or simultaneously with the HBeAg clearance in 27 patients (57.4%) and persisted but with decreasing levels for 2 to 40 months in 20 patients. Most of these patients had high alpha-fetoprotein levels or evidence of bridging hepatic necrosis. In contrast, the serum hepatitis B virus DNA was undetectable for a minimum of 3 (3-17) months in the 28 patients who had an uneventful course before HBeAg seroconversion. Twenty of these 28 patients had well-documented episodes of acute exacerbation with high hepatitis B virus DNA levels, but with normal alpha-fetoprotein and little evidence of extensive necrosis as far back as 6 to 27 months before HBeAg seroconversion.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
97.
Interferon therapy in HBeAg positive chronic hepatitis reduces progression to cirrhosis and hepatocellular carcinoma 总被引:11,自引:0,他引:11
BACKGROUND/AIMS: The long-term outcomes of interferon-alpha (IFN-alpha) therapy in hepatitis B e antigen (HBeAg) seropositive patients remain controversial. This study was conducted to address this issue. METHODS: The long-term outcomes were compared in 233 IFN-treated patients and 233 well-matched untreated controls. RESULTS: The cumulative incidence at the end of 15 years of follow-up (median 6.8 years, range 1.1-16.5 years) in the IFN-treated patients and controls was: HBeAg seroconversion 74.6% vs. 51.7% (P=0.031); hepatitis B surface antigen (HBsAg) seroclearance 3% vs. 0.4% (P=0.03); cirrhosis 17.8% vs. 33.7% (P=0.041); and hepatocellular carcinoma (HCC) 2.7% vs. 12.5% (P=0.011). Significant reduction of HCC was only observed in patients with pre-existing cirrhosis (P<0.01). Compared with untreated controls with persistent HBeAg, HBeAg seroconverters in untreated and IFN-treated group showed significantly lower incidence of cirrhosis and HCC (P=0.003-0.031), while non-seroconverters of IFN-treated group had marginally significant lower incidence of cirrhosis (P=0.065). Multivariate analysis showed that IFN therapy, HBeAg seroconversion and genotype B HBV infection are independent factors for better long-term outcomes. CONCLUSIONS: IFN therapy reduces cirrhosis and HCC development. 相似文献
98.
BACKGROUND & AIMS: Seroclearance of hepatitis B virus (HBV) surface antigen (HBsAg) is a rare event in chronic hepatitis B patients receiving lamivudine therapy. It is generally believed to be a benevolent sign, implicating clearance of viremia. The aim of this study is to examine the authenticity of this dogma. METHODS: In a 5-year period, 11 patients treated with lamivudine experienced seroclearance of HBsAg. The clinical data were examined. The HBV S gene sequences derived from the patient's serum samples before and after seroclearance of HBsAg were analyzed. RESULTS: Serum HBV-DNA could be detected by nested polymerase chain reaction (PCR) in all 11 patients, by 1-step PCR in 8, and by Cobas Amplicor HBV-DNA test (>200 copies/mL) in 5. A mutation hot spot, P120A in the S gene, was identified in 6 of the 11 patients. Site-directed mutagenesis experiments indicated that the Ausria-II RIA test failed to detect this mutant. Decreased sensitivity of detection was also observed when other monoclonal antibodies were applied. CONCLUSIONS: Seroclearance of HBsAg during lamivudine therapy may not indicate viral clearance. Specifically, it may be caused by a point mutation in the S gene, which results in detection failure. In such patients, further verification and follow-up using a sensitive HBV-DNA test are advised. 相似文献
99.
Albumin gradient and portal vein velocity in severe viral hepatitis patients complicated with ascites 总被引:3,自引:0,他引:3
BACKGROUND/AIMS: To ascertain the mechanism of development of ascites and the hemodynamic change of portal system, 28 patients who had an episode of severe viral hepatitis with and without spontaneous bacterial peritonitis were studied. METHODOLOGY: By means of a non-invasive duplex system, the relationships between the albumin gradient of serum-ascites and the portal vein velocity were assessed in 10 patients with spontaneous bacterial peritonitis and 18 patients without spontaneous bacterial peritonitis. RESULTS: In the group of patients with severe form of hepatitis but without spontaneous bacterial peritonitis, there is a significant positive linear correlation between the level of serum albumin and the albumin gradient of serum-ascites (P < 0.001). However, a receded linear correlation was found between the serum albumin and the portal vein velocity (P < 0.02), and between the albumin gradient of serum-ascites and the portal vein velocity (P < 0.027) with Spearman linear correlation analysis. CONCLUSIONS: The present study suggests that hypoalbuminemia may be related to impairment of synthesis function in severe hepatitis itself, but not to the intraabdominal shifting of protein. Decreased portal vein velocity may be the first presenting sign in patients with severe form hepatitis complicating simple ascites. Yet this relationship will be masked and complicated once spontaneous bacterial peritonitis occurs. 相似文献
100.
Clinical and Virological Course of Chronic Hepatitis B Virus Infection With Hepatitis C and D Virus Markers 总被引:2,自引:0,他引:2
Yun-Fan Liaw M.D. Sun-Lung Tsai M.D. Ph.D. I-Shyan Sheen M.D. Mei Chao Ph.D. Chau-Ting Yeh M.D. Ph.D. Sen-Yung Hsieh M.D. Ph.D. Chia-Ming Chu M.D. 《The American journal of gastroenterology》1998,93(3):354-359
Objective : Hepatitis B, C, and delta virus (HBV, HCV, HDV) share similar transmission routes; thus, dual or triple infections may occur and even persist in the same patient. However, little is known about the presentations and course of chronic HBV infection with HCV and HDV markers, which this study examined. Methods : Antibodies against HCV (anti-HCV) and HDV (anti-HDV) were assayed as appropriate in patients with HBV infection. The clinical, pathological, and virological presentations as well as the course of the disease in patients with HBV/HDV/HCV triple infection markers were then reviewed. Results : A total of 60 patients, 51 men and nine women, age 19–67 yr (mean 45.9 ± 1.6 yr) were identified. Of these 60 patients, five (8.3%) were HBeAg positive and 10 (16.7%) cirrhotic at entry, 30 (50%) presented with acute superinfection (HCV or HDV, or both) and the remaining 30 presented with chronic liver disease. On presentation, 16 (53.3%) of the 30 patients with acute superinfection showed hepatic decompensation and eight (26.7%) died. In contrast, only one of the patients with "chronic liver disease" presented with hepatic decompensation. Of the 42 patients followed up for 1–15 (mean, 4.7 ± 0.6) yr, 45.2% showed remission and 19% showed HBsAg seroclearance, whereas 12.5% of the 32 noncirrhotics developed cirrhosis and three of the nine cirrhotics became decompensated. At the end of follow-up, 29 patients (69.9%) were still seropositive for HCV-RNA but only nine (22.5%) were seropositive for HDV-RNA and five (12.5%) were seropositive for HBV-DNA. Conclusions : These results suggest that infection with HBV, HCV, and HDV triple markers is a severe disease in acute superinfection stage but that the course is relatively benign, slowly progressive, and usually dominated by HCV. 相似文献