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Occult Hepatitis B Virus Infection (occult + hepatitis_b_virus_infection)
Selected AbstractsOccult hepatitis B virus infection in a North American adult hemodialysis patient populationHEPATOLOGY, Issue 5 2004Gerald Y. Minuk Hepatitis B virus (HBV) infections continue to occur in adult hemodialysis units. A possible contributing factor is the presence of occult HBV (serum hepatitis B surface antigen [HBsAg] negative but HBV DNA positive). Two hundred forty-one adult hemodialysis patients were screened for occult HBV. HBV DNA testing was performed by real-time polymerase chain reaction (PCR) with 2 independent primer sets (core promoter and surface). Two (0.8%) of the 241 patients were HBsAg positive. Of the remaining 239 HBsAg-negative patients, 9 (3.8%) were HBV DNA positive. Viral loads in these individuals were low (102 -104 viral copies/mL). Seven of the 9 (78%) were nt 587 mutation (sG145R mutant) positive. Demographic, biochemical, and HBV serological testing did not help to identify those with occult HBV. In conclusion, the prevalence of occult HBV in adult hemodialysis patients in this North American urban center is approximately 4 to 5 times higher than standard HBsAg testing would suggest. The majority of these infections are associated with low viral loads and a high prevalence of the sG145R mutant. Finally, the demographic, biochemical, and/or serological features of HBV DNA,positive subjects do not distinguish these individuals from the remainder of the dialysis patient population. (HEPATOLOGY 2004; 40:1072,1077.) [source] Occult hepatitis B virus infection and lamivudine-resistant mutations in isolates from renal patients undergoing hemodialysisJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 1 2010Jorge S. Motta Abstract Background and Aims:, Patients undergoing hemodialysis are at risk of infection with both hepatitis B virus (HBV) and hepatitis C virus (HCV). Occult HBV infection is usually associated with low levels of HBV and is frequently detected in HCV-infected patients. The aims of the present study were to compare the prevalence of occult HBV infection among anti-HCV-positive and anti-HCV-negative patients undergoing hemodialysis, and characterize the molecular patterns of HBV isolates from patients with occult infection. Methods:, Serum samples from 100 patients negative for hepatitis B surface antigen undergoing hemodialysis, half of whom were positive for anti-HCV antibodies, were tested for the presence of HBV-DNA using semi-nested polymerase chain reaction (PCR). PCR products of the S gene were directly sequenced. Results:, HBV-DNA was detected in 15 samples. There were no significant differences in HCV status, sex, age, time of dialysis, alanine aminotransferase levels or HBV serological markers between patients with or without occult HBV infection, with the exception of antibody to hepatitis B core antigen (anti-HBc)-only serological marker (P = 0.003). All six HBV isolates that could be sequenced were of genotype A/subgenotype A1. Four of these six HBV isolates contained mutations associated with lamivudine resistance in the DNA polymerase (two with L180M/M204V and two with rt173V/180M/204V) and a specific substitution (Y100C) in the HBV small surface protein. Conclusions:, HBV isolates with the identified substitutions have the potential to spread silently by nosocomial transmission within the hemodialysis unit. These results have potential implications for the management of patients with occult HBV infection undergoing hemodialysis. [source] Occult hepatitis B virus infection in Southern African blacks with hepatocellular carcinomaJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 9 2008Michael C Kew Abstract Background and Aim:, To ascertain the prevalence of occult hepatitis B virus (HBV) infection in southern African blacks with hepatocellular carcinoma. Methods:, Sera from 118 patients negative for HBV surface antigen but positive for HBV antibodies were studied. HBV-DNA was detected using a nested polymerase chain reaction (PCR) assay and confirmed by nucleotide sequencing of the surface and precore/core genes. Results:, Surface gene HBV-DNA was detected in a single PCR assay in 48.4% of the patients. Positive results increased to 57.7% after two PCR assays (not significant) and 75.7% after four assays (P < 0.001). No false positive results were obtained in these assays or in the 15 control samples for which PCR assays were performed four times. Significant differences in positivity rates were not observed between patients positive for HBV core antibody alone and those positive for core and surface antibodies. The sensitivity of the PCR amplification of the precore/core gene was significantly less than that of the surface open reading frame: the yield of positive results was 23.7% after one assay, 32.2% after two assays (not significant), and 52% after four assays (P < 0.001). Combining the results of the assays of the two genes increased the yield of positive results for the first assay (by 11.9%, P = 0.015), but not the second (6.1%) or fourth assays (4.6%). Conclusion:, Occult HBV infection is present in the serum of the majority of hepatocellular carcinomas in southern African blacks whose serum is negative for hepatitis B surface antigen but positive for anti-HBV core antigen. The yield of positive results increases if more than one PCR assay is performed. [source] Occult hepatitis B virus infection: a covert operationJOURNAL OF VIRAL HEPATITIS, Issue 1 2010F. B. Hollinger Summary., Detection of occult hepatitis B requires assays of the highest sensitivity and specificity with a lower limit of detection of less than 10 IU/mL for hepatitis B virus (HBV) DNA and <0.1 ng/mL for hepatitis B surface antigen (HBsAg). This covert condition is relatively common in patients with chronic hepatitis C virus (HCV) that seems to exert some influence on the replicative capacity and latency of HBV. Detection of virus-specific nucleic acid does not always translate into infectivity, and the occurrence of primer-generated HBV DNA that is of partial genomic length in immunocompetent individuals who have significant levels of hepatitis B surface antibody (anti-HBs) may not be biologically relevant. Acute flares of alanine aminotransferase (ALT) that occur during the early phase of therapy for HCV or ALT levels that remain elevated at the end of therapy in biochemical nonresponders should prompt an assessment for occult hepatitis B. Similarly, the plasma from patients with chronic hepatitis C that is hepatitis B core antibody (anti-HBc) positive (±anti-HBs at levels of <100 mIU/mL) should be examined for HBV DNA with the most sensitive assay available. If a liver biopsy is available, immunostaining for hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) should be contemplated and a portion of the sample tested for HBV DNA. This is another reason for optimal collection of a specimen (e.g. two passes with a 16-guage needle under ultrasound guidance). Transmission of HBV to immunosuppressed orthotopic liver transplant recipients by donors with occult hepatitis B (OHB) will continue to occupy the interests of the transplant hepatologist. As patients with OHB may have detectable HBV DNA in serum, peripheral blood mononuclear cells (PBMC) and/or liver that can be reactivated following immunosuppression or intensive cytotoxic chemotherapy, the patient needs to be either monitored or treated depending on the pretreatment serological results such as an isolated anti-HBc reaction or a detectable HBV DNA. [source] Occult hepatitis B virus infection in patients with autoimmune liver diseasesLIVER INTERNATIONAL, Issue 3 2009Sarah P. Georgiadou Abstract Background: Occult hepatitis B virus (HBV) infection is characterized by undetectable serum HBV surface antigen (HBsAg) but detectable HBV-DNA in serum or liver. Aims: To determine the prevalence and clinical impact of occult HBV in autoimmune liver diseases as similar data are missing. Methods: One hundred and ninety-six sera samples from HBsAg-negative patients, including 66 autoimmune hepatitis (AIH), 93 primary biliary cirrhosis (PBC) and 37 primary sclerosing cholangitis (PSC), were investigated for HBV-DNA using the polymerase chain reaction (PCR) before treatment initiation. One hundred and three serial samples from 38 AIH patients under immunosuppression and 282 selected blood donors (HBsAg negative; antibodies to HBV-core antigen positive) were also investigated. Fourteen available paraffin-embedded AIH liver samples were also investigated for HBV-DNA by nested-PCR. Results: Hepatitis B virus DNA was detected in the serum of 24/196 patients (12.2%) and 0/282 donors (P=0.0000). Nine patients had AIH (13.6%), eight had PBC (8.6%) and seven had PSC (18.9%) (P=0.0000 vs healthy). HBV-DNA detection in AIH livers was higher than in serum. HBV-DNA was associated neither with HBV markers nor with epidemiological, laboratory and clinical data. Serial testing of AIH patients revealed two HBV-DNA-negative patients before treatment becoming positive during treatment, while all HBV-DNA-positive patients before immunosuppression became negative. Conclusion: Based mainly on serum HBV-DNA, we found a significant proportion of autoimmune liver disease patients with occult HBV compared with donors. However, taking into account our results in a small number of liver tissues, it should be emphasized that occult HBV could be even higher when both serum and liver specimens are investigated. Occult HBV does not seem to affect the clinical and laboratory features of the diseases, while AIH patients with occult HBV under immunosuppression do not deteriorate during follow-up. [source] Occult hepatitis B virus infection in liver transplant recipients with recurrent hepatitis C: relationship with donor age and fibrosis progressionCLINICAL TRANSPLANTATION, Issue 2 2009Pierluigi Toniutto Abstract:, Liver transplantation (OLT) recipients who receive a graft from donors positive for hepatitis B virus (HBV) anti-core antibodies may develop overt "de novo" HBV infection. The study was undertaken to explore how often HBV infection may remain occult after OLT for hepatitis C, and whether it may represent a factor of graft fibrosis progression. We studied 30 consecutive patients transplanted for hepatitis C liver disease. Specimens from the native liver and from the graft were searched for occult HBV infection (O-HBV). In the native liver, 8/30 patients had detectable O-HBV; during the follow-up, O-HBV infection was demonstrated in 14 graft specimens. Graft O-HBV was associated with older donor age (,50 yr; 8/9 vs. 6/21, p < 0.005). Recipients with graft O-HBV and no O-HBV in the native liver who received their grafts from donors aged >40 yr had faster fibrosis progression than recipients with no post-transplant O-HBV, whose grafts came from donors aged >40 yr and recipients whose grafts came from donors aged ,40 yr (4/7 vs. 1/7 vs. 2/16, p < 0.05). In OLT recipients, O-HBV is more likely to occur when grafts are obtained from aged donors and may affect the rate of fibrosis progression because of recurrent hepatitis C. [source] Prevalence and impact of occult hepatitis B infection in chronic hepatitis C patients treated with pegylated interferon and ribavirin,JOURNAL OF MEDICAL VIROLOGY, Issue 5 2010Marion Levast Abstract The prevalence of occult hepatitis B, defined by absence of HBsAg and HBV DNA, ranges widely in patients with hepatitis C. This may influence the treatment of hepatitis C and the severity of liver disease. Sensitive and specific real-time PCR techniques are available commercially and can detect more reliably low HBV DNA levels. The aim of this study was to determine the prevalence of occult hepatitis B virus infection using the COBAS Taqman assay (Roche Diagnostics, Meylan, France) in the serum and liver of HBsAg negative patients with chronic hepatitis C and to evaluate its clinical consequences on liver pathology and its impact on the response to treatment with peg-IFN, and Ribavirin. HBV DNA detection was assessed retrospectively on 140 sera and 113 liver biopsies of HCV positive/HBsAg negative patients before treatment. A 4.4% (5/113) prevalence of occult hepatitis B was recorded in liver samples and in none of the sera. Anti-HBc was not detected in one, three of whom were sustained virological responders to treatment, one was relapsed responder and one was non-responder. Furthermore, in this cohort composed of 12% anti-HBs negative/anti-HBc positive and 20% anti-HBs positive/anti-HBc positive patients, anti-HBc was not associated with pre-therapeutic viral load, ALT serum levels, and histological activity or fibrosis. Using a commercial real-time PCR assay, we observed a low prevalence of occult B hepatitis. This, just as anti-HBC status, had no clinical impact in a large cohort of hepatitis C patients. It therefore does not appear useful to screen for occult hepatitis B in these patients with this test before beginning HCV treatment. J. Med. Virol. 82: 000,000, 2010. © 2010 Wiley-Liss, Inc. J. Med. Virol. 82: 747,754, 2010. © 2010 Wiley-Liss, Inc. [source] Role of surface promoter mutations in hepatitis B surface antigen production and secretion in occult hepatitis B virus infection,JOURNAL OF MEDICAL VIROLOGY, Issue 3 2007Sonali Sengupta Abstract The production, secretion, and localization of surface proteins of hepatitis B virus (HBV) and the ratio of large to small surface protein S was studied in HepG2 cells transfected with the wild-type and mutant pre-S1 and pre-S2/S promoters of HBV molecular clones 313.1 (GenBank accession no. AY161147) and 761.1 (GenBank accession no. AY161159) from two patients with occult HBV infection. Fusion constructs were made by in frame fusion of the wild-type surface gene to the mutant pre-S1 and pre-S2/S promoters and wild-type promoter so that the structural part of the small surface protein remains identical. HepG2 cells transfected transiently were used for analysis. HBV surface proteins production and secretion was determined by enzyme linked immuno assay (ELISA) and localization by immunofluorescence. Immunoprecipitation of the large, middle, and small surface protein was carried out in transient transfected and metabolically labeled cells to determine the ratio of the large to small surface protein. The results indicate that HepG2 cells transfected with mutant HBV promoters had reduced HBV surface proteins secretion compared to wild-type HBV. HepG2 cells transfected with mutant HBV pre-S1 and pre-S2/S promoters showed cytoplasmic aggregation of HBV surface proteins compared to wild-type HBV promoters, which showed diffuse cytoplasmic localization. In all cases, the HBV surface proteins localized to the endoplasmic reticulum. The ratio between the large and small surface protein was 1.89 and 0.56 with mutant HBV 313.1 and 761.1 pre-S1 and pre-S2/S promoters, respectively, compared to 0.17 in wild-type. Thus, the aggregation of surface proteins, altered ratio and secretion of surface proteins were possibly the causes of occult hepatitis B infection. J. Med. Virol. 79:220,228, 2007. © 2007 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||