Hepatitis C virus infection after renal transplantation: viral load and outcome

Effect of conversion from calcineurin inhibitors to everolimus on hepatitis C viremia in adult kidney transplant recipients

Introduction:

Currently, there is no specific immunosuppressive protocol for hepatitis C (HCV)-positive renal transplants recipients. Thus, the aim of this study was to evaluate the conversion effect to everolimus (EVR) on HCV in adult kidney recipients.

Method:

This is an exploratory single-center, prospective, randomized, open label controlled trial with renal allograft recipients with HCV-positive serology. Participants were randomized for conversion to EVR or maintenance of calcineurin inhibitors.

Results:

Thirty patients were randomized and 28 were followed-up for 12 months (conversion group, Group 1 =15 and control group, Group 2 =13). RT-PCR HCV levels reported in log values were comparable in both groups and among patients in the same group. The statistical analysis showed no interaction effect between time and group (p value G*M= 0.852), overtime intra-groups (p-value M=0.889) and between group (p-value G=0.286). Group 1 showed a higher incidence of dyslipidemia (p=0.03) and proteinuria events (p=0.01), while no difference was observed in the incidence of anemia (p=0.17), new onset of post-transplant diabetes mellitus (p=1.00) or urinary tract infection (p=0.60). The mean eGFR was similar in both groups.

Conclusion:

Our study did not show viral load decrease after conversion to EVR with maintenance of antiproliferative therapy.

Harmful effects of viral replication in seropositive hepatitis C virus renal transplant recipients

BACKGROUND

Seropositivity for hepatitis C virus (HCV) predicts lower patient and graft survival after renal transplantation (RT). However, the influence of viral replication at transplantation on long-term outcome remains to be determined.

METHODS

This was a retrospective study conducted in four Spanish hospitals, from 1997 to 2006. Data of all patients with RT, who displayed HCV+ (enzyme-linked immunosorbent assay), and with negative viremia at RT (NEG group) were collected (n=41). For each NEG patient enrolled, data of two patients with RT nearest in time, HCV+, and positive viremia (POS group) were also collected (n=78).

RESULTS

The POS group showed a higher incidence of long-term liver disease (56.4% vs. 24.4%, P=0.0009) and episodes of transaminase elevation (38.5% vs. 7.3%, P=0.0003) and worse renal function (serum creatinine [sCr], 3.0 [2.7] vs. 1.9 [1.6] mg/dl, P=0.032; glomerular filtration rate, 43.7 [22.4] vs. 56.9 [27.9] ml/min, P=0.075). Noteworthy, 24.4% of NEG patients reactivated after RT, showing a worse patient survival (P=0.039). Active viral replication at RT and dialysis requirement in the first week remained as independent predictors of lower graft survival (death censored): hazards ratio, 3.11 (95% confidence interval, 1.34-7.19; P=0.009) and hazards ratio 3.13 (95% confidence interval, 1.53-6.37; P=0.002).

CONCLUSIONS

This study shows that active viral replication at transplantation is an independent risk factor for graft failure in patients with positive serology for HCV.

Cyclosporin A inhibits hepatitis C virus replication and restores interferon-alpha expression in hepatocytes

Hepatitis C virus (HCV) infection is the leading indication for liver transplantation and a major cause of graft failure. This study investigated whether cyclosporin A (CsA), a widely used immunosuppressant for organ transplantation, inhibits full cycle HCV replication and restores type I interferon (IFN) signaling pathway in human hepatocytes. CsA treatment of hepatocytes before, during, and after HCV infection significantly inhibited full cycle viral replication, which is evidenced by decreased expression of HCV RNA, protein, and infectious viruses in human hepatocytes. The suppression of HCV replication by CsA was associated with elevated levels of endogenous IFN-α in infected hepatocytes. Although CsA had little effect on IFN-α signaling pathway in uninfected hepatocytes, CsA treatment of HCV-infected hepatocytes specifically upregulated the expression of IFN regulatory factor-1 and inhibited the expression of suppressor of cytokine signaling-1 and protein inhibitor of activated signal transducers and activators of transcription-x, the primary negative regulators of IFN signaling pathway. These findings provide additional evidence to support the development of CsA-based prevention/treatment of HCV infection for transplant recipients.

Hepatitis C and renal transplantation: a review on historical aspects and current issues

Chronic liver disease has a significant impact on the survival of renal transplant recipients with an incidence rate of 4-38%. Approximately, 8-28% of renal transplant recipients die due to chronic liver disease. Hepatitis C seems to be the leading cause of chronic liver disease in kidney recipients. Hepatitis C virus (HCV) infection has a wide range of prevalence (2.6-66%) among renal transplant recipients living in different countries with great genotype diversity in different parts of the world. Nowadays, antiviral drugs are used for the management of hepatitis C. Because of graft-threatening effects of some antiviral drugs used in HCV-infected renal transplant recipients, we specifically focused on HCV treatment after renal transplantation. Treatment of post-renal transplantation chronic liver disease with INF and ribavirin remains controversial. Anecdotal reports on post-renal transplantation hepatitis C demonstrate encouraging findings. This review summarises the most current information on diagnosis, treatment, prognosis, complications as well as the new aspects of treatment in HCV-infected renal transplant recipients. HCV belongs to the family of Flaviviridae, genus Hepacivirus.

Hepatitis C virus reactivation in anti-hepatitic C virus-positive renal transplant recipients

From 1992 to 2001 hepatitis C virus (HCV) viremia was studied in 53 renal transplant recipients anti-HCV+ with at least 3 months follow-up posttransplant using a quantitative retrotranscriptase-PCR method. HCV-RNA was detected in 45 (85%): 29 of the 34 recipients treated with azathioprine-based therapy and 15 of 18 treated with mycophenolate mofetil. Immunosuppressive therapy type did not affect HCV replication. Three different patterns of HCV-RNA evolution were detected: 13 (28.8%) patients with high RNA-HCV levels; 21 (46.7%) patients with low levels; and 11 (24.4%) patients with viremia elevation. In 10 (90%) of 11 of the last group, HCV viremia was detected before 15 days posttransplantation, significantly earlier than in the other two groups. Thus, replication during the first 15 days after transplantation leads to a high RNA-HCV viral load. No clinical symptoms were related to HCV.

Treatment of Hepatitis C in Solid Organ Transplantation

Hepatitis C virus (HCV) infection is highly prevalent worldwide, and results in significant morbidity and mortality. HCV frequently infects haemodialysis patients and appears to impact on long-term survival of kidney transplant recipients. Therefore, treatment is recommended for kidney transplant candidates before transplantation and should be avoided following transplantation because of a high risk of allograft rejection. HCV infection does not appear to influence survival in cardiac transplant recipients and cardiac transplant recipients should also not be treated. In general, HCV-infected patients with cirrhosis are not considered as candidates for either kidney or cardiac transplantation given their risk of decompensation. HCV is the most common indication for liver transplantation and re-infection with varying degrees of liver injury is universal. Survival after liver transplantation is reduced among HCV-infected patients when compared with uninfected controls. Therefore, treatment using interferon and ribavirin is advocated; however, such therapy is frequently limited by adverse effects. Thus, improved antiviral treatment modalities are eagerly awaited in the transplant setting.