Treatment of hepatitis B and C after liver transplantation. Part 2, hepatitis C

Outcome after liver re-transplantation in patients with recurrent chronic hepatitis C

Long-term outcome after liver retransplantation for recurrent hepatitis C has been reported to be inferior to other indications. The identification of factors associated which improved long-term results may help identify hepatitis C positive patients who benefit from liver retransplantation. Outcome after liver retransplantation for recurrent hepatitis C was analyzed in 18 patients (group 1) and compared with hepatitis C positive patients undergoing liver retransplantation for initial nonfunction (group 2, n=11) and patients with liver retransplantation for other indications (group 3, n=169). Five-year patient survival following retransplantation for groups 1, 2 and 3 was 59% 84% and 60%. Increased alanine aminotransferase (ALT) and serum bilirubin, as well as white cell count and MELD score at day of retransplantation were associated with impaired patient outcome. Five-year survival after retransplantation in patients with recurrent hepatitis C is similar to that in patients undergoing liver retransplantation for other indications. Our analysis showed MELD score, bilirubin, ALT levels and white cell counts preorthotopic liver transplantation are important predictive factors for outcome. This observational study may help select patients and identify the optimal time-point of liver retransplantation in ''Hepatitis C'' virus positive patients in the future.

Factors influencing the progression of fibrosis in patients with recurrent hepatitis C after liver transplantation under antiviral therapy: a retrospective analysis of 939 liver biopsies in a single center

Recurrent hepatitis C after liver transplantation (LT) is a major problem, since up to 30% of patients develop cirrhosis only 5 years after LT in the absence of antiviral therapy. The aim of this study was to examine the rate of progression of fibrosis and its associated risk factors in patients submitted to an early antiviral treatment post-LT. Included in the study were 105 patients submitted to LT between September 1990 and December 2004, 70 of whom were treated with interferon and/or ribavirin. A total of 939 liver biopsies were studied. The median fibrosis stage was 0.8 after 1 year post-LT, 1.1 after 3 years, 1.3 after 5 years, and 1.5 after 10 years. LT recipients with fibrosis >2 (13% at 10 years) had a significantly reduced survival rate (63% vs. 87% at 10 years, P = 0.03). Univariate analysis disclosed that recipient male gender, antiviral therapy before LT, LT after 1998, induction immunosuppressive regimen including tacrolimus, induction immunosuppressive regimen including mycophenolate (or without azathioprine), and short duration of prednisolone (<12 months) were significantly associated with progression of fibrosis. In a multivariate analysis, recipient male gender (P = 0.04), antiviral treatment before LT (P = 0.001), and initial immunosuppressive regimen without azathioprine (P = 0.03) were associated with progression of fibrosis. In conclusion, our study has documented that fibrosis progression is not linear over time and that occurrence of severe fibrosis is related to previously described factors related to immunosuppressive regimen or donor age and also to a past history of pre-LT antiviral therapy.

Operational tolerance in clinical liver transplantation: emerging developments

There is still little understanding of the immune events that occur in transplant patients as they develop a relationship with their graft alloantigens. Though, there is an enormous interest and motivation in inducing specific unresponsiveness to organ allografts in order to allow minimization or complete withdrawal of immunosuppression in the recipient, given that life-long immunosuppressive treatment entails a high risk of infectious and metabolic complications, malignancies, and drug-specific toxicity. Clinical tolerance is defined as stable normal graft function in the total absence of a requirement for maintenance immunosuppression. Effective clinical tolerance has been reported more frequently in liver transplant recipients than after transplantation of other organs, as the liver is an immune-privileged organ for several mechanisms, most of which still remain unclear. According to the English medical literature, cautious, carefully supervised weaning of immunosuppressive drugs in controlled trials is not unreasonable, especially when monitored by protocol biopsies. The five centers in which the weaning has been attempted have reported a similar degree of success (1 out of 4 patients) and no harm to the patient over the short-term. Though, long-term follow-up has been lacking and, at present, there are no reliable immunological parameters that enable patients who can be withdrawn from immunosuppressants without the risk of rejection to be identified. To achieve that goal, appropriate collaboration and interaction between clinicians, immunologists and other basic scientists are desirable, as well as the creation of an international, maybe intercontinental, registry for tolerant patients.

Treatment of hepatitis C infection

HCV infection is one of the leading causes of chronic liver disease worldwide,and it results in cirrhosis, liver failure, and HCC. As a result, hepatitis C cirrhosis has become the principal indication for liver transplantation. Ironically,HCV infection can be cured with available antiviral therapies, but only a minority of infected persons has ever been treated. The current standard of therapy isa combination of PEG-IFNalpha and ribavirin, which produces high rates of SVRs(absence of detectable HCV RNA at least 24 weeks after cessation of therapy):42% to 56% in genotype 1 and 75% to 84% in genotypes 2 and 3. Recent reports indicate that the less frequent genotypes 4, 5, and 6 also are responsive to combination therapy. Recommendations for treatment of conventional and special patient populations were reviewed in detail. Newer therapeutics that are entering clinical trials provide hope that SVRs may be possible in patients who are difficult to treat and in nonresponders to current therapy.

Pegylated interferon alpha-2b for patients with HCV recurrence and graft fibrosis following liver transplantation

Chronic hepatitis C is a principal indication for liver transplantation. Recurrent viral infection is inevitable and graft disease is common. We report tolerability, safety and efficacy of pegylated interferon alpha 2b (PEG-IFN) monotherapy for patients with hepatitis C virus (HCV) recurrence and fibrosis after liver transplantation. Repeated measurements of serum HCV titer permitted assessment of the kinetics of the antiviral response for all patients. We screened 63 patients transplanted for HCV at our center for antiviral treatment, 14 were eligible and treated, but only 6 completed the proposed 52 weeks of therapy. Eight were withdrawn because of severe/life-threatening side effects/events, including liver dysfunction (4 patients). None of those 8 achieved a sustained virological response (SVR). Five of 6 who completed treatment were HCV RNA negative at the end of treatment, and 2 achieved an SVR. Viral kinetics were similar to published observations for treatment of non-transplanted HCV patients. Patients with genotype non-1 infection displayed a more rapid decline of viral titer than was observed for genotype 1 infection. Post-transplant HCV patients are frequently unsuitable for, or intolerant of PEG-IFN. Liver dysfunction was a major concern.

The prevention of infection post-transplant: the role of prophylaxis, preemptive and empiric therapy

The close linkage of infection with the nature and intensity of the transplant immunosuppressive program has led to the concept of the therapeutic prescription. This has two components: an immunosuppressive one to prevent or treat rejection and graft-versus-host disease and an antimicrobial one to make it safe. This review provides a conceptual framework to approach the risk and risk periods for infection in solid organ and hematopoietic stem cell transplant recipients as well as an approach to antimicrobial use in this population.