1/13. association of lamivudine resistance in recurrent hepatitis B after liver transplantation with advanced hepatic fibrosis.BACKGROUND: Orthotopic liver transplantation (OLT) in patients with hepatitis b virus (HBV) infection is known to be associated with a high recurrence rate and poor prognosis. lamivudine, a nucleoside analogue, is a potent inhibitor of HBV replication, but it is associated with a 14-39% rate of resistance. methods: We report on four patients who underwent OLT for HBV infection. In all cases, the HBV infection recurred in the grafted liver and was treated with lamivudine (100 mg daily) on a compassionate-use basis. The patients were monitored closely for serum liver enzymes, hepatitis B surface antigen and HBV dna (by hybridization). Liver biopsy was performed before and after lamivudine therapy. HBV dna was amplified from serum for each patient and sequenced through a conserved polymerase domain, the tyrosine-methionine-aspartate-aspartate (YMDD) locus. RESULTS: All four patients exhibited lamivudine resistance 9-20 months after initiation of the drug. In all patients with a clinically mild disease, liver histology findings (12-24 months after lamivudine therapy) showed progressive fibrosis as compared to biopsies performed before lamivudine therapy, with a significant increase (> or =2 points) in the Knodell score in three patients. Moreover, two patients exhibited worsening of the necroinflammatory process. A mutation at the YMDD motif of the HBV polymerase gene was detected in all cases. CONCLUSIONS: lamivudine resistance frequently occurs in patients with recurrent HBV infection after OLT and is associated with advanced hepatic fibrosis and necroinflammatory process. A combination of antiviral therapies may be necessary.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/13. Genetic evaluation of the dysplasia-carcinoma sequence in chronic viral liver disease: a detailed analysis of two cases and a review of the literature.Hepatocellular carcinoma (HCC) is one of the most frequent human malignancies, especially in Asia and africa, but also in the western world its incidence is increasing. HCC is a complication of chronic liver disease with cirrhosis as the most important risk factor. Viral co-pathogenesis due to hepatitis b virus (HBV) and hepatitis c virus (HCV) infection seems to be an important factor in the development of HCC. Curative therapy is often not possible due to the late detection of HCC. Thus, it is attractive to find parameters which predict malignant transformation in HBV- and HCV-infected livers. In the past decade, preneoplastic lesions, i.e. dysplastic foci or nodules, have gained interest as possible markers for imminent malignancy. Noteworthy, dysplastic liver lesions are increasingly detected by imaging techniques. We describe here two cases of chronic viral liver disease, one HBV-and one HCV-related, in which dysplastic lesions were present adjacent to HCC. In the HBV case, a (smaller) satellite of HCC was present as well. The neoplastic specimens were investigated by comparative genomic hybridization (CGH) and in situ hybridization (ISH). Both methods revealed multiple genetic alterations in the HCCs. The genetic patterns of the HBV-related HCC and the satellite tumor showed many shared alterations suggesting a clonal relationship. A subset of genetic changes were already present in dysplasias illustrating their preneoplastic nature. Surrounding liver cirrhosis samples did not display chromosomal aberrations. A literature survey illustrates the relative paucity of information concerning genetic alterations in preneoplastic liver lesions. However, all the data strongly suggests a role for liver cell dysplasia as a precursor condition of liver cell cancer.- - - - - - - - - - ranking = 2keywords = hybridization (Clic here for more details about this article) |
3/13. Reactivation of hepatitis b virus infection with an unusual pattern of serological markers.A 73-year-old man presented with acute hepatitis, judged to be a reactivation of hepatitis b virus infection. His serum samples during a follow-up time of 16 months showed an unusual pattern of serological markers. He was consistently HBeAg positive, HBsAg fluctuated just under the cut-off value and he had a low level of circulating anti-HBs. By electron microscopy numerous aggregates of surface antigen particles, but not complete virions were seen. He was HBV dna positive by hybridization. The complete precore and core genes and a region of the surface gene were amplified from his serum by PCR. These findings emphasize the need for expanded serological testing in some patients with acute clinical hepatitis.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
4/13. Successful treatment with tenofovir in a child C cirrhotic patient with lamivudine-resistant hepatitis b virus awaiting liver transplantation. Post-transplant results.Antiviral treatment can be complex in decompensated hepatitis b virus (HBV) cirrhosis because of potential emergence of lamivudine-resistant mutants and worsening liver function, and to multifactorial nephrotoxicity. Negative HBV-dna status by hybridization before liver transplantation is a favorable prognostic factor. We present the case of a 54-year-old HBV liver transplantation candidate who, after testing negative for HBV-dna, developed YMDD lamivudine-resistant mutants resulting in a deteriorated clinical condition. After 8 months of adefovir plus lamivudine double therapy, only partial response was achieved. Tenofovir was added to this regimen, and an early decline of HBV-dna was seen at 4 weeks without adverse events. The patient underwent transplantation. At 21-month postoperative follow-up, the patient's outcome was excellent. Post-transplantation HBV prophylaxis, taking into account the prior development of mutants, consists of hepatitis B immunoglobulin plus lamivudine and adefovir. Tenofovir was well tolerated and produced a fast antiviral response, suggesting its potential value in combined antiviral treatment for liver transplantation candidates.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
5/13. hepatitis b virus variant, with a deletion in the preS2 and two translational stop codons in the precore regions, in a patient with hepatocellular carcinoma.We analyzed hepatitis b virus (HBV) genomes obtained from serum samples and liver biopsy specimen of a chronic HBsAg/anti-HBe carrier with hepatocellular carcinoma (HCC). Before the liver biopsy, performed at the time of HCC diagnosis, the patient had been followed for 2 years; the serum samples collected in that period resulted negative for HBV-dna dot blot hybridization. The hepatic dna was at first examined by Southern blot, but no HBV sequence was detected. polymerase chain reaction (PCR) amplification revealed the presence of HBV genomes in dna extracted from the liver tissue and from two serum samples collected, respectively, 1 and 2 years before the biopsy. Direct sequence of the amplified preC/C and preS regions showed that the viral populations present in serum and liver were identical and that they had a 34 nucleotide deletion in the preS2 region, while the preC region presented two mutations each introducing a translational stop codon, one at the carboxy terminal end and the other at the second codon of the region, both able to prevent HBeAg expression. These results identify a new HBV variant which was selected during a chronic infection, and had very low levels of replication as shown by its detection only after PCR amplification.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
6/13. Study of preneoplastic changes of liver cells by immunohistochemical and molecular hybridization techniques.The status of hepatitis b virus dna was investigated by in situ hybridization in multifocal areas of a noncancerous hepatitis b virus-associated cirrhosis. This liver exhibited a marked degree of dysplasia and adenomatous hyperplasia. The results of these studies were correlated with the histopathology and immunohistochemical stains for hepatitis B core and surface antigens. There was clear evidence of a marked reduction to absence of hepatitis B viral dna by in situ hybridization and absence of HBc and HBsAg in the foci of liver cell dysplasia and adenomatous hyperplasia. These results support the hypothesis that liver cell dysplasia and adenomatous hyperplasia are preneoplastic in nature.- - - - - - - - - - ranking = 6keywords = hybridization (Clic here for more details about this article) |
7/13. Lymphoproliferative disease of granular lymphocytes in a patient with concomitant hepatitis b virus infection of CD4 lymphocytes.In this report we studied a 35-year-old male who developed an abnormal expansion of granular lymphocytes (GL) which spontaneously regressed over a period of 2 years. The immunological and molecular characterizations of expanded cells showed the CD3 ,CD8 ,HNK-1 phenotype, a polyclonal organization of the T-cell receptor beta-chain gene and normal natural killer activity. At the time of presentation, spot and blot hybridization techniques revealed the presence of viral hepatitis b virus (HBV) dna sequences only in highly enriched CD4 T cells, while proliferating GL were negative. With this as a background, we addressed the question of whether in our case the polyclonal GL proliferation represented an immunoreactive response against CD4 infected cells. In particular, we tested the possibility that expanded GL could be cytotoxic against autologous infected CD4 cells. At the time of the first determination, when several of the CD4 cells harbored HBV, GL showed a minimal degree of cytotoxicity against 51Cr-labeled CD4 cells; 2 years later, when GL became capable of lysing these targets, the appearance of the specific cytotoxicity was concomitant with the disappearance of the HBV-infected CD4 cells and with the recovery of granular lymphocytosis. Taken together, our data suggest that in this case GL proliferation could represent an immunoreactive process against CD4 cells.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
8/13. Primary hepatocellular carcinoma with hepatitis b virus-dna integration in a 4-year-old boy.The autopsy findings in a case of hepatocellular carcinoma with hepatitis b virus (HBV)-dna integration in a Japanese boy, 4 years and 10 month of age, are reported. The boy was an HBV carrier born in a typical familial cluster of HBV infection in japan. He had been asymptomatic until the sudden manifestation of the liver tumor. Histopathologic examination revealed a well-differentiated, adult-type hepatocellular carcinoma without hepatic cirrhosis. HBV-dna sequences were detected in the tumor cell dna by the Southern blot hybridization method. This is the youngest patient with hepatocellular carcinoma with HBV-dna integration reported to date, suggesting that HBV may manifest its oncogenic properties after a shorter incubation period than generally believed.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
9/13. Determination of HBV dna in serum in a case of needlestick hepatitis.HBV dna in serum was determined by modified spot hybridization. A nurse of the dialysis staff was inoculated via needlestick with blood of a HBsAg-positive hemodialysis patient, who had 2000 pg HBV dna per milliliter serum. After insufficient passive immunization the nurse developed transient anicteric hepatitis B. HBV dna was positive in sera of the recipient before and at the beginning of the elevation of transaminases.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
10/13. Asymmetric replication of hepatitis b virus dna in human liver: demonstration of cytoplasmic minus-strand dna by blot analyses and in situ hybridization.In situ and blot hybridization techniques have been used with strand- and region-specific probes to characterize the forms of hepatitis b virus (HBV) dna in the liver of a patient with chronic active hepatitis B. The hepatocytes contain a heterogeneous population of rapidly migrating dna species in the 0.5-1.4 kb position that are localized predominantly in the cytoplasm and are of minus-strand polarity. The findings indicate that the replication is asymmetric, with separate pathways for plus- and minus-strand synthesis of HBV dna; that viral dna synthesis is initiated at a site near the nick in the minus strand of virion dna; and that actively replicating forms of HBV dna can be identified at the cellular level by in situ hybridization.- - - - - - - - - - ranking = 6keywords = hybridization (Clic here for more details about this article) |
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