Search

Recurrent infection with HCV after liver transplantation (LT) is almost universal and is associated with substantial morbidity, mortality and graft loss. In contrast to immunocompetent individuals, HCV infection in immunosuppressed transplant recipients usually has an accelerated course. Acute hepatitis develops in approximately 75% of HCV recipients in the first six months following LT. Within the five years after LT, over 80% of HCV-infected liver transplant recipients develop histologic evidence of chronic allograft injury secondary to HCV, with up to 30% of cirrhosis. While the choice of calcineurin inhibitors has not clearly shown to affect the histologic HCV recurrence or the frequency of rejection in HCV-infected recipients, the cumulative exposure to corticosteroids is associated with increased mortality, higher levels of HCV viremia, and more severe histologic recurrence. Successful therapy has been shown to have a positive impact on both graft and patient survival. Combination therapy with interferon (pegylated and non-pegylated forms) plus ribavirin appears to provide maximum benefits. Drug therapy is usually administered for recurrent disease. No prophylactic therapy is available. Preemptive regimens offer no distinctive advantages over treatments for recurrent disease. Overall, treatment is poorly tolerated, with frequent need for dose reductions, especially due to cytopenias, and drug discontinuation in up to 50% of patients. Optimizing drug doses is important in maximizing sustained virologic response rates (SVR). The SVR achieved is between 33% and 42% in randomized studies treating patients with histologic recurrence. The potential factors that influence this low SVR rate are:1) genotype 1 virus; 2) high viral load; 3) prior nonresponding to therapy; 4) side effects of antiviral treatment; 5) use of growth factors; and 6) effect of immunosuppression. In post-transplant patients with recurrent HCV disease, combination peg alpha-2b or alpha-2a in standard dose and ribavirin (800-1200 mg either ab initio or as an increasing dose) regimen for 48 weeks was significantly better than no therapy but not than any other therapy.

Recurrent infection with HCV after liver transplantation is almost universal and is associated with substantial morbidity, mortality and graft loss. In contrast to immunocompetent individuals, HCV infection in immunosuppressed transplant recipients usually has an accelerated course. Acute hepatitis develops in approximately 75% of HCV recipients in the first six months following orthotopic liver transplantation (OLT). By the fifth postoperative year, over 80% of HCV-infected liver transplant recipients will develop histologic evidence of chronic allograft injury secondary to hepatitis C, with up to 30% developing cirrhosis. While the choice of calcineurin inhibitor has not been clearly shown to affect histologic recurrence of hepatitis C or the frequency of rejection in HCV-infected recipients, cumulative exposure to corticosteroids is associated with increased mortality, higher levels of HCV viremia and more severe histologic recurrence. Unfortunately, treatment of chronic HCV in liver transplant recipients is suboptimal. Combination therapy with interferon (pegylated and nonpegylated forms) plus ribavirin appears to provide maximum benefits. Drug therapy is usually administered for recurrent disease. No prophylactic therapy is available. Preemptive regimens offer no distinctive advantages over treatments initiated for recurrent disease. Overall, treatment is poorly tolerated, with frequent need for dose reductions, especially for cytopenias, and drug discontinuation in up to 50% of patients. Optimizing drug doses is important in maximizing sustained virologic response rates. The achieved SVR is between 33% and 42% in randomized studies treating patients with histologic recurrence and 0% to 33% when used in a preemptive protocol. The potential factors that influence this low SVR rate are: 1) high percentage of patients with genotype 1 virus; 2) high viral load at the start of treatment; 3) high percentage of prior non-responders to therapy; 4) side effects that often make the use of standard doses and duration of treatment difficult; 5) the use or not of growth factors; and 6) the effect of immunosuppression. In post-transplant patients with recurrent HCV disease, combination Peg alfa-2b or alfa-2a in standard dose and ribavirin (800-1200 mg either ab initio or as an increasing dose) regimen for 48 weeks was significantly better than no therapy, but not than any other therapy.

End-stage liver disease associated with hepatitis C virus (HCV) infection is the most common indication for orthotopic liver transplantation (OLT) and accounts for 50% of these procedures in Spain and 42% of OLT performed in the United States. Recurrent infection with HCV after OLT, however, is almost universal and is associated with substantial morbidity, mortality, and graft loss. In contrast to immunocompetent individuals, HCV infection in immunosuppressed transplant recipients usually has an accelerated course. Acute hepatitis develops in approximately 75% of HCV recipients in the first six months following OLT. By the fifth postoperative year, over 80% of HCV-infected liver transplant recipients will develop histologic evidence of chronic allograft injury secondary to hepatitis C, with up to 30% developing cirrhosis. While the choice of calcineurin inhibitor has not been clearly shown to affect the histologic recurrence of hepatitis C or the frequency of rejection in HCV-infected recipients, cumulative exposure to corticosteroids is associated with increased mortality, higher levels of HCV viremia and more severe histologic recurrence. There have been no well-controlled, large, prospective, multicenter and randomized clinical trials to determine the optimal approach to the treatment of recurrent HCV infection following OLT. Most published studies were small, lacked controls, had short follow-up periods, and were devoid of histologic analysis. Furthermore, most of the published studies are largely incomparable due to differences in the definition of recurrent hepatitis C, timing of anti-HCV therapy administration relative to transplantation, the drugs and doses used and regimens employed, and the study end points assessed (i. e. biochemical, virologic and histologic end points have not all been consistently investigated). In lieu of large studies in post-transplant patients, monotherapy with conventional interferon or monotherapy with pegylated interferon should be considered in recipients with histologically confirmed recurrence of HCV infection. The role of hepatitis C immunoglobulin and new imunosuppression agents in the management of post-transplant HCV infection is still evolving.

The relationship between the complexity of the hypervariable region 1 (HVR1) quasispecies of hepatitis C virus (HCV) and responsiveness to interferon-alpha (IFN) therapy was studied in patients with chronic hepatitis C. Twelve HCV-RNA-positive patients were treated daily with high dose IFN and ribavirin for 4 weeks, and then with IFN 3 MIU (Million International Units) TIW (three times per week) and ribavirin for 6 months. The HVR1 quasispecies complexity was analyzed by nested polymerase chain reaction-mediated single-strand conformation polymorphism (SSCP). The baseline HCV-RNA levels in the study group ranged from 10(6) to 10(7) copies/ml. All patients exhibited HCV genotype 1 b. Initial SSCP analysis revealed four (33.3%) patients with a low complexity pattern (SSCP bands < or =4) and eight (66.6%) patients with high complexity pattern (SSCP bands >4). After 4 weeks of IFN therapy, one patient became HCV negative, and among those remaining positive, the HCV-RNA levels decreased by 2 to 3 logs and the number of SSCP decreased by 2 to 3 bands per sample. After 6 months of IFN therapy, five (41.7%) patients became HCV-RNA-negative. Seven (58.3%) patients did not respond to IFN therapy with sustained viral load from 10(3) to 10(5) copies/ml, and high complexity SSCP patterns. Our data support the HVR quasispecies complexity to be an independent predictive factor for IFN responsiveness in patients infected with HCV.