Prophylaxis of hepatitis B virus infection before liver transplantation, 1990-2001: a single-center experience

Molecular characterization of occult hepatitis B virus infection in patients with end-stage liver disease in Colombia

Background

Hepatitis B virus (HBV) occult infection (OBI) is a risk factor to be taken into account in transfusion, hemodialysis and organ transplantation. The aim of this study was to identify and characterize at the molecular level OBI cases in patients with end-stage liver disease.

Methods

Sixty-six liver samples were obtained from patients with diagnosis of end-stage liver disease submitted to liver transplantation in Medellin (North West, Colombia). Samples obtained from patients who were negative for the surface antigen of HBV (n = 50) were tested for viral DNA detection by nested PCR for ORFs S, C, and X and confirmed by Southern-Blot. OBI cases were analyzed by sequencing the viral genome to determine the genotype and mutations; additionally, viral genome integration events were examined by the Alu-PCR technique.

Results

In five cases out of 50 patients (10%) the criteria for OBI was confirmed. HBV genotype F (subgenotypes F1 and F3), genotype A and genotype D were characterized in liver samples. Three integration events in chromosomes 5q14.1, 16p13 and 20q12 affecting Receptor-type tyrosine-protein phosphatase T, Ras Protein Specific Guanine Nucleotide Releasing Factor 2, and the zinc finger 263 genes were identified in two OBI cases. Sequence analysis of the viral genome of the 5 OBI cases showed several punctual missense and nonsense mutations affecting ORFs S, P, Core and X.

Conclusions

This is the first characterization of OBI in patients with end-stage liver disease in Colombia. The OBI cases were identified in patients with HCV infection or cryptogenic cirrhosis. The integration events (5q14.1, 16p13 and 20q12) described in this study have not been previously reported. Further studies are required to validate the role of mutations and integration events in OBI pathogenesis.

Treatment of chronic hepatitis B: recommendations from an Italian workshop

The changing scenario of hepatitis B virus therapy has encouraged the organisation of a workshop, endorsed by three Italian scientific societies, aimed at defining the current recommendations for hepatitis B virus treatment. Liver histology and stage of disease remain fundamental for treatment decisions; interferon and nucleoside/nucleotide analogues-based therapy represent different strategies for different phases of the hepatitis B virus disease. The recommendations defined: new and lower cut-off of hepatitis B virus-DNA for eligibility to therapy according to disease stage, how to optimise the use of nucleoside/nucleotide analogues and to individualise the monitoring of response and what to do with treatment failures. Specific recommendations have also been given for cirrhosis patients, those immune suppressed and co-infected with HIV and other hepatitis viruses.

Adefovir dipivoxil for wait-listed and post-liver transplantation patients with lamivudine-resistant hepatitis B: final long-term results

Wait-listed (n = 226) or post-liver transplantation (n = 241) chronic hepatitis B (CHB) patients with lamivudine-resistant hepatitis B virus (HBV) were treated with adefovir dipivoxil for a median of 39 and 99 weeks, respectively. Among wait-listed patients, serum HBV DNA levels became undetectable (<1,000 copies/mL) in 59% and 65% at weeks 48 and 96, respectively. After 48 weeks, alanine aminotransferase (ALT), albumin, bilirubin, and prothrombin time normalized in 77%, 76%, 60%, and 84% of wait-listed patients, respectively. Among posttransplantation patients, serum HBV DNA levels became undetectable in 40% and 65% at weeks 48 and 96, respectively. After 48 weeks, ALT, albumin, bilirubin, and prothrombin time normalized in 51%, 81%, 76%, and 56% of posttransplantation patients, respectively. Among wait-listed patients who underwent on-study liver transplantation, protection from graft reinfection over a median of 35 weeks was similar among patients who did (n = 34) or did not (n = 23) receive hepatitis B immunoglobulin (HBIg). Hepatitis B surface antigen was detected on the first measurement only in 6% and 9% of patients who did or did not receive HBIg, respectively. Serum HBV DNA was detected on consecutive visits in 6% and 0% of patients who did or did not receive HBIg, respectively. Treatment-related adverse events led to discontinuation of adefovir dipivoxil in 4% of patients. Cumulative probabilities of resistance were 0%, 2%, and 2% at weeks 48, 96, and 144, respectively. In conclusion, adefovir dipivoxil is effective and safe in wait-listed or posttransplantation CHB patients with lamivudine-resistant HBV and prevents graft reinfection with or without HBIg.

The first one thousand liver transplants in Turin: a single-center experience in Italy

The first Italian liver transplant center to reach the goal of 1000 procedures was Turin. The paper reports this single-center experience, highlighting the main changes that have occurred over time. From 1990 to 2002, 1000 consecutive liver transplants were performed in 910 patients, mainly cirrhotics. Surgical technique was based on the preservation of the retrohepatic vena cava of the recipient. The veno-venous bypass was used in 30 cases only and abandoned since 1997. Operating time, warm ischemia time and length of hospital stay significantly decreased over the years, while operating room extubation became routine. Immunosuppression pivoted on cyclosporine A. Management of retransplantations, marginal grafts, and of HCV-positive, HBV-positive and hepatocellular carcinoma recipients were optimized. Median follow-up of the patients was 41 months. Overall survival rates at 1, 5 and 10 years were 87%, 78% and 72% respectively. Survival rates obtained in the second half of the cases (1999-2002 period) were significantly better than those obtained in the first half (1990-1998 period) (90% vs. 83% at 1 year and 81% vs. 76% at 5 years respectively). Increasing experience in liver transplant surgery and postoperative care allowed standardization of the procedure and expansion of the activity, with parallel improvement of the results.

Four years of treatment with lamivudine: clinical and virological evaluations in HBe antigen-negative chronic hepatitis B

AIM

To evaluate the clinical and virological impact of the prolonged use of lamivudine in 94 patients with HBe antigen-negative chronic hepatitis B.

METHODS

Initial virological and biochemical responses were obtained in 84 (89%) and in 83 (88%) patients respectively.

RESULTS

The virological response peaked within the first 12 months, but diminished to 39% at 48 months because of drug resistance. Overall a virological breakthrough developed in 44 patients (52.4%). After virological breakthrough, the actuarial probability of maintaining biochemical remission diminished to 15% at 24 months and 0% at 29 months. There was no response in 10.6%. Polymerase gene mutations were observed in 82.5% of virological breakthroughs but also in 75% of the non-responders. Overall 7.4% of patients developed a hepatocellular carcinoma.

CONCLUSION

Almost 90% of patients responded initially to lamivudine but the emergence of drug resistance progressively reduced the rate of virological remission to 39% at the fourth year of therapy. YMDD mutants explained the 75% of lamivudine resistances and were also selected very early in non-responders. Although the biochemical response is invariably lost within 29 months of the YMDD mutant's duration, the clinical outcome was benign despite severe postvirological breakthrough hepatitic flares in about 12% of cases.

Occult hepatitis B virus infection in HBsAg negative patients undergoing liver transplantation: clinical significance

Occult Hepatitis B virus (o-HBV) infection has been reported in HB surface antigen (HBsAg)-negative liver donors whose risk of transmitting HBV justifies a specific prophylaxis in liver recipients. The clinical significance of o-HBV infection in HBsAg-negative recipients and their need for prophylaxis is unknown. Liver samples collected during surgery from 23 HBsAg-negative patients (9 liver donors and 14 recipients) and 20 HBsAg-positive recipients (controls) were studied by polymerase chain reaction with an independent set of primers mapping the core and surface HBV genes. Intrahepatic HBV DNA was detected as core and surface genes in all the HBsAg-positive recipients, in none of the HBsAg-negative donors and in 9/14 (64%) of the HBsAg-negative recipients (2 HCV negative, 7 HCV positive). The intrahepatic amount of HBV was significantly lower in HBsAg-negative than in HBsAg-positive livers (median values 1.36 Log(10)/microg DNA vs. 3.66 Logs, p<0.0001, core gene, and 1.13 vs. 6.21 Logs p<0.0001, surface gene). No HBV DNA was detected in plasma from o-HBV recipients; one of them tested positive in lymphocytes. No correlation was found between o-HBV and serologic markers of previous HBV exposure, response to vaccination, acute rejection, hepatitis D and G virus-infections. None of o-HBV carriers experienced a de novo hepatitis B after transplantation (median follow-up: 477 days). Occult HBV is frequent in HBsAg-negative liver recipients. It is not associated with increased episodes of acute rejection, coinfection with hepatotropic viruses, different responses to HBV vaccination, or the development of de-novo hepatitis B. In o-HBV infection a particular virus-host interaction can explain the low intrahepatic HBV content and the lack of extrahepatic HBV replication, thus justifying the low risk of hepatitis B reactivation, in absence of specific prophylaxis, once the recipient liver is removed.