Hepatitis C virus infection in hemodialysis patients

Investigation of a Case of Genotype 5a Hepatitis C Virus Transmission in a French Hemodialysis Unit Using Epidemiologic Data and Deep Sequencing

BACKGROUND Hepatitis C virus (HCV) is a major cause of chronic liver disease worldwide. A patient was recently found to be HCV seropositive during hemodialysis follow-up. OBJECTIVE To determine whether nosocomial transmission had occurred and which viral populations were transmitted. DESIGN HCV transmission case. SETTING A dialysis unit in a French hospital. METHODS Molecular and epidemiologic investigations were conducted to determine whether 2 cases were related. Risk analysis and auditing procedures were performed to determine the transmission pathway(s). RESULTS Sequence analyses of the NS5b region revealed a 5a genotype in the newly infected patient. Epidemiologic investigations suggested that a highly viremic genotype 5a HCV-infected patient who underwent dialysis in the same unit was the source of the infection. Phylogenetic analysis of NS5b and hypervariable region-1 sequences revealed a genetically related virus (>99.9% nucleotide identity). Deep sequencing of hypervariable region-1 indicated that HCV quasispecies were found in the source whereas a single hypervariable region-1 HCV variant was found in the newly infected patient, and that this was identical to the major variant identified in the source patient. Risk analysis and auditing procedures were performed to determine the transmission pathway(s). Nosocomial patient-to-patient transmission via healthcare workers' hands was the most likely explanation. In our dialysis unit, this unique incident led to the adjustment of infection control policy. CONCLUSIONS The data support transmission of a unique variant from a source with a high viral load and genetic diversity. This investigation also underlines the need to periodically evaluate prevention and control practices.

Antiviral treatment with sofosbuvir and simeprevir in a kidney transplant recipient with HCV-decompensated cirrhosis: viral eradication and removal from the liver transplant waiting list

Hepatitis C positive kidney transplant (KT) recipients are a difficult-to-treat subpopulation. Interferon-based therapies are contraindicated (or at least not used) in KT patients, due to the risk of allograft rejection, its poor tolerability and the low rates of sustained virological response (SVR) achieved with these therapies. Nevertheless, the use of direct-acting antiviral drugs (DAAs) will certainly provide new opportunities for hepatitis C treatment in the KT setting. Here, we report the case of a KT recipient with decompensated cirrhosis who received antiviral therapy with sofosbuvir, simeprevir, and ribavirin during 24 weeks while awaiting liver transplantation. Hepatitis C was eradicated, and the patient was removed from the transplant list. Although there is no safety and efficacy data regarding the use of DAAs in the KT setting, this case suggests that KT recipients may benefit from the use of new antiviral drugs with high SVR rates and an excellent safety profile.

Utilization of Signal-to-Cutoff Ratio of Hepatitis C Virus Antibody Assay in Predicting HCV Viremia among Hemodialysis Patients

BACKGROUND

Hepatitis C virus (HCV) infection is a common cause of acute and chronic hepatitis among the hemodialysis population. To prevent cross infection between hemodialysis patients during the hemodialysis procedure, routine screening of anti-HCV antibody is recommended. However, a reactive anti-HCV EIA test is not equal to active HCV infection. An expensive RT-PCR study is required to confirm HCV viremia. This will significantly increase the cost burden because payment for each hemodialysis treatment is very low in Taiwan. Thus, it is useful to identify parameters that could predict HCV viremia among anti-HCV-reactive patients. In this study, we examined the usefulness of signal-to-cut (S/CO) ratio of anti-HCV antibody in discriminating HCV viremia from non-viremia among the anti-HCV-reactive hemodialysis population.

MATERIALS AND METHODS

In a cross-sectional measurement of anti-HCV antibody among 369 chronic hemodialysis patients, 44 showed reactive and 9 grey zone reaction for anti-HCV. These 53 patients underwent further blood tests for the measurement of AST, ALT and HCV RNA (by RT-PCR). The results of RT-PCR were used as a dependent variable. Then, S/CO ratios of anti-HCV, serum AST, ALT levels, age and duration of hemodialysis were used as independent variables to undergo ROC curve and logistic regression analysis.

RESULTS

Thirty-six of the 53 reactive and grey zone patients were positive for HCV RNA in the RT-PCR study. Patients who were positive for HCV RNA had a higher S/CO ratio (p < 0.01), higher AST and ALT levels (p < 0.01), and longer duration on hemodialysis (p < 0.05) than those negative for HCV RNA. Logistic regression revealed that only S/CO ratio was a significant predictor for HCV viremia (p = 0.004). ROC curve analysis showed that S/CO ratio had a highest area under curve (0.967, p < 0.001), followed by ALT (0.826, p < 0.001), AST (0.778, p = 0.001), duration on hemodialysis (0.606, p = 0.215) and age (0.426, p = 0.386) in discriminating HCV viremia from non-viremia. Using a cutoff S/CO ratio of 65, we can confirm HCV viremia with a diagnostic specificity of 100%, sensitivity of 80.1% and positive predictive value of 100%.

CONCLUSION

S/CO ratio is a useful indicator in predicting HCV viremia among anti-HCV-reactive hemodialysis patients. Patients with an S/CO ratio >65 can be regarded as those with active HCV infection. Alternatively, patients with reactive anti-HCV but with an S/CO ratio <65 should receive further RT-PCR test.

Kidney transplantation threshold in patients with hepatitis C: a decision analysis model

BACKGROUND

There are no standard guidelines for the permissible degree of liver fibrosis in patients with chronic hepatitis C virus prohibiting cadaveric renal transplantation (CRT).

METHODS

A decision analysis model was constructed to compare 5-year patient survival using three strategies for patients on hemodialysis. The probabilities of pretransplant and posttransplant survival, progression of liver fibrosis, CRT, and sustained viral response were obtained from a systematic review of the literature. Sensitivity analyses were performed.

RESULTS

Kidney transplantation was associated with improved 5-year survival for patients with fibrosis stages 1 to 3, but not stage 4 (cirrhosis). Antiviral therapy was associated with improvement in survival in patients with stage 3 fibrosis. The 5-year survival was similar for patients with stage 4 irrespective of the option of antiviral therapy. The model was sensitive to varying the probability of both pretransplant and posttransplant survival.

CONCLUSION

There appears to be no overall 5-year survival benefit in treating S1 and S2 fibrosis patients with hepatitis C virus antiviral therapy before CRT. There is no benefit in overall 5-year survival in patients with cirrhosis and thus should not be candidates for CRT.

The association of hepatitis C virus infection with the prognosis of chronic hemodialysis patients: A retrospective study of 3,064 patients between 1999 and 2010

The prevalence of hepatitis C virus (HCV) infection is high among patients receiving chronic hemodialysis. To clarify the risk ratio of HCV infection with respect to mortality and prognosis in chronic hemodialysis patients, a retrospective longitudinal cohort study was conducted in 2010 and involved 3,064 patients receiving chronic hemodialysis at nine dialysis facilities in Hiroshima, Japan, who were recruited from 1999 to 2003. Logistic regression and Cox hazards models were used to estimate the mortality risk among hemodialysis patients. Among the patients, 422 (14.0%) were positive for HCV RNA. HCV RNA positivity was associated with death in the logistic model (adjusted odds ratio = 1.79; P < 0.001). However, it was not a risk factor for the reduced of survival rate in the Cox proportional hazard model (adjusted risk ratio = 1.07; P = 0.4138). In summary, among hemodialysis patients, HCV RNA is correlated with the mortality rate; however, it is not significantly correlated with prognosis in terms of survival time. On the other hand, diabetes and age at dialysis onset are significantly correlated with survival. Diabetes control treatment should be preferentially selected for hemodialysis patients, and antiviral therapy for HCV should be introduced based on the clinical state of the patient. J. Med. Virol. 87:1558–1564, 2015. © 2015 The Authors. Journal of Medical Virology published by Wiley Periodicals, Inc.

New therapies for hepatitis C: considerations in patients with renal impairment

Hepatitis C virus (HCV) is a major public health issue because infection may lead to liver failure, cirrhosis and hepatocellular carcinoma. In patients with renal dysfunction, hepatitis C can also worsen the underlying renal disease. Treating HCV infection is thus mandatory in this population. New therapies for hepatitis C have recently been developed, and some have been launched. Most of them are used in combination with the current standard of care, ribavirin and pegylated interferon alfa. Some of them can be used in regimens without ribavirin and/or pegylated interferon. However, few data are available on dosage adjustment for renal function in patients receiving these very new drugs. We reviewed the literature on this subject and gathered information, although scarce, to propose guidelines for using these drugs in patients with chronic kidney disease.

Relevance of low viral load in haemodialysed patients with chronic hepatitis C virus infection

AIM

To identify predictors of sustained virological response in hemodialysed patients treated by PEGinterferon α for chronic hepatitis C, genotype 1.

METHODS

The sustained virological response (SVR) rate, IL28B genotype, IFNL4 genotype, initial viral load (IVL) and other pretreatment variables in 39 end-stage renal disease patients (ESRD) on maintenance haemodialysis (HD) infected with hepatitis C virus (HCV), genotype 1b, were compared with a control group of 109 patients with normal kidney function treated within the same period. All the patients were treatment naïve and had well compensated liver disease. The ESRD patients received 135 μg of PEGylated interferon α-2a (PegIFN-α) weekly and a reduced dose of ribavirin (RBV) was administered to 23/39 patients with an initial haemoglobin level > 10 g/dL. Control group patients were given standard doses of PegIFN-α and RBV. SVR was assessed as HCV RNA negativity 24 wk post-treatment. A t-test or ANOVA were used for comparisons of the means and a χ(2) test compared the frequencies. Logistic regression was used to determine significant predictors of SVR. Cutoff values for continuous variables were obtained from Receiver Operating Characteristic analysis.

RESULTS

The distribution of IL28B rs12979860 CC, CT and TT genotypes in the ESRD group was 28.2%, 64.1% and 7.7%, respectively, and 19.3%, 62.4% and 18.3% in the controls. The IFNL4 genotype was in almost absolute linkage disequlibrium with IL28B. The proportion of patients with a low IVL (< 600000 IU/mL) was significantly higher in the ESRD group than in the controls (28/39, 71.8% vs 51/109, 46.8%, P = 0.009), as was the proportion of patients with low IVL in IL28B CC carriers compared with non-CC carriers in the ESRD group (10/11, 90.9% vs 18/28, 64.3%, P = 0.0035). This difference was not found in the controls (7/22, 31.8% vs 44/87, 50.6%, P = 0.9). The overall SVR rate was 64.1% (25/39) in the ESRD group and 50.5% (55/109) in the control group (P = 0.19). 11/11 (100%) and 19/22 (86.4%) IL28B CC patients achieved SVR in the ESRD and control groups, respectively. A statistically significant association between SVR and IL28B and IFNL4 variants was found in both groups. The ESRD patients who achieved SVR showed the lowest IVL [median 21000, interquartile range (IQR): 6000-23000 IU/mL], compared with ESRD individuals without SVR (1680000, IQR: 481000-6880000, P = 0.001), controls with SVR (387000, IQR: 111000-1253000) and controls without SVR (905000, IQR: 451000-3020000). In ESRD, an IVL < 600000 IU/mL was strongly associated with SVR: 24/28 (85.7%) patients who achieved SVR had viraemia below this threshold.

CONCLUSION

Haemodialysis decreases the viral load, especially in IL28B CC genotype carriers. A low IVL was the strongest predictor of SVR in ESRD patients identified in multivariate analysis.

Management of hepatitis C in patients with chronic kidney disease

Hepatitis C virus (HCV) infection is highly prevalent among chronic kidney disease (CKD) subjects under hemodialysis and in kidney transplantation (KT) recipients, being an important cause of morbidity and mortality in these patients. The vast majority of HCV chronic infections in the hemodialysis setting are currently attributable to nosocomial transmission. Acute and chronic hepatitis C exhibits distinct clinical and laboratorial features, which can impact on management and treatment decisions. In hemodialysis subjects, acute infections are usually asymptomatic and anicteric; since spontaneous viral clearance is very uncommon in this context, acute infections should be treated as soon as possible. In KT recipients, the occurrence of acute hepatitis C can have a more severe course, with a rapid progression of liver fibrosis. In these patients, it is recommended to use pegylated interferon (PEG-IFN) in combination with ribavirin, with doses adjusted according to estimated glomerular filtration rate. There is no evidence suggesting that chronic hepatitis C exhibits a more aggressive course in CKD subjects under conservative management. In these subjects, indication of treatment with PEG-IFN plus ribavirin relies on the CKD stage, rate of progression of renal dysfunction and the possibility of a preemptive transplant. HCV infection has been associated with both liver disease-related deaths and cardiovascular mortality in hemodialysis patients. Among those individuals, low HCV viral loads and the phenomenon of intermittent HCV viremia are often observed, and sequential HCV RNA monitoring is needed. Despite the poor tolerability and suboptimal efficacy of antiviral therapy in CKD patients, many patients can achieve sustained virological response, which improve patient and graft outcomes. Hepatitis C eradication before KT theoretically improves survival and reduces the occurrence of chronic graft nephropathy, de novo glomerulonephritis and post-transplant diabetes mellitus.