Liver-kidney recipients with chronic viral hepatitis C treated with interferon-alpha

Protein tyrosine phosphatase non-receptor type 22 (PTPN22) gene polymorphisms in liver transplant donors and impact on acute cellular liver transplant rejection

The PTPN22 gene encodes the lymphoid protein tyrosine phosphatase involved in regulation the immune response. The single nucleotide polymorphisms (SNPs) rs1217388, rs1310182, rs2476601, and rs2488457 are located within the PTPN22 gene. We investigated whether these SNPs in liver transplant donors are associated with acute cellular rejection in the recipients. The SNPs were analyzed in donors (n = 104) of recipients who did not develop an acute cellular rejection and in donors (n = 53) of corresponding recipients developing an acute cellular rejection. No significant differences in genotype and allele frequencies of these SNPs were detected in either of the group. Our data suggest that these SNPs in liver transplant donors have no impact on the susceptibility of acute cellular liver transplant rejection.

Hepatitis C Virus in the Renal Transplant Population: An Update With Focus on the New Era of Antiviral Regimens

Chronic hepatitis C virus infection is a global health problem, especially among renal transplant recipients. Herein, we present an overview of hepatitis C virus among renal transplant patients, with a focus on some updated aspects concerning types of viral genotypes, methods of diagnosis, the effects of renal transplant on hepatitis C virus infection, and summary of hepatitis C virus-related complications after renal transplant. We also discuss patient and graft survival rates and the present and future therapeutic options with special focus on new antiviral and possible interactions with immunosuppressive medications.

Management of chronic hepatitis C virus infection in patients with end-stage renal disease: a review

Infection with hepatitis C virus (HCV) is highly prevalent in chronic kidney disease (CKD) patients, mainly in those on hemodialysis (HD). The seroprevalence of HCV in developing countries ranges between 7% and 40%. Risk factors for this infection in the CKD population include the number of blood transfusions, duration of end-stage renal disease (ESRD), and prevalence of HCV in HD. Chronic HCV infection in patients with ESRD is associated with an increase in morbidity and mortality in the pre and post kidney transplant periods. The increase in mortality is directly associated with liver complications and an elevated cardiovascular risk in HCV-infected patients on hemodialysis. Antiviral treatment may improve the prognosis of patients with HCV, and standard interferon remains the cornerstone of treatment. Treatment of HCV in patients with CKD is complex, but achieving a sustained viral response may decrease the frequency of complications after transplantation. It appears that HCV-infected patients who remain on maintenance dialysis are at increased risk of death compared with HCV patients undergoing renal transplantation.

Interferon-based anti-viral therapy for hepatitis C virus infection after renal transplantation: an updated meta-analysis

BACKGROUND

Hepatitis C virus (HCV) infection is highly prevalent in renal transplant (RT) recipients. Currently, interferon-based (IFN-based) antiviral therapies are the standard approach to control HCV infection. In a post-transplantation setting, however, IFN-based therapies appear to have limited efficacy and their use remains controversial. The present study aimed to evaluate the efficacy and safety of IFN-based therapies for HCV infection post RT.

METHODS

We searched Pubmed, Embase, Web of Knowledge, and The Cochrane Library (1997-2013) for clinical trials in which transplant patients were given Interferon (IFN), pegylated interferon (PEG), interferon plus ribavirin (IFN-RIB), or pegylated interferon plus ribavirin (PEG-RIB). The Sustained Virological Response (SVR) and/or drop-out rates were the primary outcomes. Summary estimates were calculated using the random-effects model of DerSimonian and Laird, with heterogeneity and sensitivity analysis.

RESULTS

We identified 12 clinical trials (140 patients in total). The summary estimate for SVR rate, drop-out rate and graft rejection rate was 26.6% (95%CI, 15.0-38.1%), 21.1% (95% CI, 10.9-31.2%) and 4% (95%CI: 0.8%-7.1%), respectively. The overall SVR rate in PEG-based and standard IFN-based therapy was 40.6% (24/59) and 20.9% (17/81), respectively. The most frequent side-effect requiring discontinuation of treatment was graft dysfunction (14 cases, 45.1%). Meta-regression analysis showed the covariates included contribute to the heterogeneity in the SVR logit rate, but not in the drop-out logit rate. The sensitivity analyses by the random model yielded very similar results to the fixed-effects model.

CONCLUSIONS

IFN-based therapy for HCV infection post RT has poor efficacy and limited safety. PEG-based therapy is a more effective approach for treating HCV infection post-RT than standard IFN-based therapy. Future research is required to develop novel strategies to improve therapeutic efficacy and tolerability, and reduce the liver-related morbidity and mortality in this important patient population.

Excessive immunosuppression as a potential cause of poor survival in simultaneous liver/kidney transplantation for hepatitis C

Appropriate recipient selection of simultaneous liver/kidney transplantation (SLKT) remains controversial. In particular, data on liver graft survival in hepatitis C virus-infected (HCV+) SLKT recipients are lacking. We conducted a single-center, retrospective study of HCV+ SLKT recipients (N = 25) in comparison with HCV- SLKT (N = 26) and HCV+ liver transplantation alone (LTA, N = 296). Despite backgrounds of HCV+ and HCV- SLKT being similar, HCV+ SLKT demonstrated significantly impaired 5-year liver graft survival of 35% (HCV- SLKT, 79%, P = 0.004). Compared with HCV+ LTA, induction immunosuppression was more frequently used in HCV+ SLKT. Five-year liver graft survival rate for HCV+ SLKT was significantly lower than that for LTA (35% vs. 74%, respectively, P < 0.001). Adjusted hazard ratio of liver graft loss in HCV+ SLKT was 4.9 (95% confidence interval 2.0-12.1, P = 0.001). HCV+ SLKT recipients were more likely to succumb to recurrent HCV and sepsis compared with LTA (32% vs. 8.8%, P < 0.001 and 24% vs. 8.8%, P = 0.030, respectively). Ten HCV+ SLKT recipients underwent anti-HCV therapy for recurrent HCV; only 1 achieved sustained virological response. HCV+ SLKT is associated with significantly decreased long-term prognosis compared with HCV- SLKT and HCV+ LTA.

Treatment of hepatitis C after kidney transplant: a pooled analysis of observational studies

Various authors have given IFN-based therapy for hepatitis C among renal transplant recipients but the efficacy and safety of this approach remains unclear. A systematic review of the literature with a meta-analysis of clinical studies was performed in order to assess efficacy and safety of antiviral therapy (IFN-based therapy) in renal transplant recipients with hepatitis C virus infection. The primary outcomes were sustained virological response (as a measure of efficacy) and/or drop-out rate (as a measure of tolerability). The random-effects model of DerSimonian and Laird was used, with heterogeneity and sensitivity analyses. Sixteen studies (187 unique patients) were identified, one being controlled study. The summary estimate for sustained virological response and dropout rate was 0.34 (95% confidence intervals: 0.27, 0.42) and 0.32 (95% CI: 0.21, 0.44), respectively. The studies were heterogeneous with regard to dropout rate but not to sustained viral response. The most common side-effect requiring interruption of treatment was graft dysfunction (n = 27; 51%). Stratified analysis reported a higher rate of drop-outs in those studies based on IFN monotherapy (pooled event rate, 0.43; 95% CI: 0.25, 0.63). Meta-regression analysis showed an inverse relationship between reference year (P = 0.019), length of IFN therapy (P = 0.029) and drop-out rate. IFN-based therapy has inadequate safety and tolerance after renal transplantation. The reasons for the high rate of graft dysfunction after IFN have not been fully elucidated. Antiviral treatment of hepatitis C among kidney graft recipients continues to be a challenge to transplant physicians.

Hepatotoxicity and drug interactions in liver transplant candidates and recipients

In this article the medications that have been shown to increase rates of drug-induced liver injury in patients with cirrhosis and the important drug-drug interactions in recipients of liver transplantation are reviewed. In general, the risk of drug-induced liver injury in patients with cirrhosis does not seem to be higher when compared with the noncirrhotic population. There are, however, 2 classes of agents that have been implicated-medications used to treat tuberculosis and medications used to treat human immunodeficiency virus infection. However, with careful monitoring, even significant interactions can be effectively managed.