Search results for "HBsAg"
showing 10 items of 127 documents
Hepatitis B surface antigen presentation and HLA-DRB1*– lessons from twins and peptide binding studies
2005
Summary The aim of this study was to investigate the underlying mechanisms of the genetic association between certain HLA-DRB1* alleles and the immune response to HBsAg vaccination. Therefore, HBsAg peptide binding to HLA-DR molecules was measured in vitro by peptide binding ELISAs. Additionally, HBsAg-specific T cell reaction and cytokine profile of immune response were analysed ex vivo in ELISPOT assays and DR-restriction of T-cell proliferative responses was investigated with HBsAg specific T cell clones. In addition, we compared HBsAg specific T cell responses of 24 monozygotic and 3 dizygotic twin pairs after HBsAg vaccination. Our results showed that the peptide binding assays did not…
The influence of major histocompatibility complex class II genes and T-cell Vbeta repertoire on response to immunization with HBsAg.
1998
Nonresponsiveness to HBsAg vaccination is observed in 5-10% of vaccine recipients and is possibly caused by a defect in the T helper cell compartment. The immune response to HBsAg is influenced by genes of the major histocompatibility complex. We have investigated MHC class I and class II antigens in 53 adult responders and 73 nonresponders. Results obtained in this first study were tested in a second study with 56 responders and 62 nonresponders from an infant vaccination trial. In addition, the peripheral Vbeta-chain T-cell receptor repertoire was investigated using monoclonal antibodies and flow-cytometry in 26 adult responders and 38 nonresponders. As previously reported, nonresponsiven…
Impact of comorbidities on the severity of chronic hepatitis B at presentation.
2011
AIM: To evaluate the clinical relevance of each cofactor on clinical presentation of chronic hepatitis B. METHODS: Out of 1366 hepatitis B surface antigen (HBsAg) positive subjects consecutively observed in 79 Italian hospitals, 53 (4.3%) showed as the only cofactor hepatitis D virus (HDV) infection [hepatitis B virus (HBV)/HDV group], 130 (9.5%) hepatitis C virus (HCV) (group HBV/HCV), 6 (0.4%) human immunodeficiency virus (HIV) (group HBV/HIV), 138 (10.2%) alcohol abuse (group HBV/alcohol); 109 (8.0%) subjects had at least two cofactors and 924 were in the cofactor-free (CF) group. RESULTS: Compared with patients in group CF those in group HBV/alcohol were older and more frequently had ci…
The importance of HCV on the burden of chronic liver disease in Italy: a multicenter prevalence study of 9,997 cases
2005
Knowledge of the current epidemiology of chronic liver disease in Italy is mostly obsolete and fragmentary for the lack of up-to-date consistent data. In 2001, a 6-month prevalence study was undertaken in 79 hospitals to assess the characteristics of chronic liver disease in Italy. Both prevalent and incident cases were enrolled. A total of 9,997 patients were recruited, of whom 939 (9.4%) had normal liver biochemistry, 6,210 (62.1%) had chronic hepatitis, 1,940 (19.4%) had liver cirrhosis, and 341 (3.4%) had hepatocellular carcinoma (HCC). In 567 patients (5.7%) the diagnosis was not established. Hepatitis C virus (HCV) was found in 69.9% of the patients and was the only etiological factor…
HBV reactivation in patients with HCV/HBV cirrhosis on treatment with direct-acting antivirals
2017
Anecdotal reports suggest that patients with chronic hepatitis C virus (HCV) hepatitis and overt or occult hepatitis B virus (HBV) coinfection may reactivate HBV when HCV is suppressed or cleared by direct-acting antivirals (DAAs). We assessed the prevalence of overt or previous HBV coinfection and the risk of HBV reactivation in patients with HCV cirrhosis treated with DAAs. This was a retrospective cohort of 104 consecutive patients with HCV cirrhosis treated with DAAs. Serum HCV-RNA and HBV-DNA were tested at weeks 4, 8 and 12 of DAAs therapy and at week 12 of follow-up. At the start of DAAs, eight patients (7.7%) were HBsAg positive/HBeAg negative with undetectable HBV-DNA and low level…
The burden of HBV infection in HCV patients in Italy and the risk of reactivation under DAA therapy
2019
Background: There is increasing awareness of HBV reactivation in HCV-RNA-positive/HBV-coinfected patients with chronic liver disease (CLD) treated with oral direct-acting antivirals (DAAs). Aim: To provide figures on the prevalence of HBV markers in HCV-RNA-positive subjects in Italy, where these findings are lacking. Methods: All subjects aged ≥18 years with CLD consecutively referring to Italian liver units located throughout country were prospectively enrolled in two national surveys in 2001 and 2014. Results: The total number of HCV-RNA-positive cases was 6984; 356 (5.1%) subjects vaccinated against HBV were excluded. A total of 6628 cases were evaluated. The prevalence rates of HBsAg, …
Hepatitis delta infection in Italian patients: towards the end of the story?
2016
Background: The endemicity of hepatitis delta virus infection in Italy has decreased in the last decades. Aim: To evaluate the current epidemiology of chronic delta infection in Italy and to compare the present findings with the corresponding figures from the previous studies. Methods: A cross-sectional study involving 16 referral centres scattered all over the country in 2014. Results: Out of the 513 hepatitis B surface antigen-positive subjects enrolled, 61 (11.9%) were anti-delta positive, with a sex ratio (M/F) of 2.05. The majority (80.3%) of them was 50 years or older, while the proportion of subjects younger than 30 years of age was as low as 3.3%. No difference was detected by geogr…
Characteristics of hepatocellular carcinoma in Italy.
1998
This study aimed to assess the main features of hepatocellular carcinoma at the time of diagnosis in Italy, particularly in relation to the presence or absence of underlying cirrhosis, hepatitis virus marker patterns, age of the subjects and alpha-foetoprotein values.A total of 1148 patients with hepatocellular carcinoma seen at 14 Italian hospitals in the 1-year period from May 1996 to May 1997 were the subjects of this prevalence study. Both newly diagnosed cases (incident cases) and cases diagnosed before May 1996 but still attending the hospitals during the study period (prevalent cases) were included.We found that 71.1% of cases were positive for hepatitis C virus antibodies but negati…
Can the serological status of anti-HBc alone be considered a sentinel marker for detection of occult HBV infection?
2008
Some individuals have “occult” infection with hepatitis B virus (HBV), defined as presence of HBV genome in the serum or liver tissue without HBV surface antigen (HBsAg) in the serum. The aim of this study was to investigate whether serum antibodies against HBV core antigen in isolation (“anti-HBc alone”) are a useful marker of “occult” HBV in patients with or without hepatitis C virus (HCV) infection. “Anti-HBc alone” was detected in the sera of 119/6,544 (1.8%) asymptomatic outpatients referred to the diagnostic laboratory for routine testing for viral hepatitis, 62/607 (10.2%) drug users, and 42/195 (21.5%) patients with hepatocellular carcinoma. Using three in-house nested-PCR amplifica…
Differential genetic determination of immune responsiveness to hepatitis B surface antigen and to hepatitis A virus: a vaccination study in twins.
2002
Summary Background The course of viral hepatitis is thought to be affected by genetic host variability and, in particular, by genes of the major histocompatibility locus. Hepatitis A and B vaccination is a useful model to study the effect of host factors on the immune response to viral antigens. We aimed to assess the heritability of the HBsAg (anti-HBs) and anti-hepatitis A virus (anti-HAV) immune response and to estimate the effect of the HLA-DRB1 locus and other genetic loci unlinked to HLA. Methods We did an open prospective study and vaccinated 202 twin pairs with a combined recombinant HBsAg/inactivated hepatitis A vaccine. We measured antibodies to HBsAg and HAV and determined HLA-DR…