Interferon treatment for chronic hepatitis C virus infection in uremic patients

When and how can nephrologists treat hepatitis C virus infection in dialysis patients?

Hepatitis C virus (HCV) infection, a major cause of end-stage liver disease, is a common comorbidity in patients on dialysis and causes increased morbidity and mortality. Historically HCV has been extremely difficult to cure with interferon and ribavirin-based therapies, which are also associated with significant side effects, and few dialysis patients ever received HCV treatment. However, in the last 4 years, interferon-free direct-acting antiviral therapies have been approved, and several combinations have been studied in dialysis patients. A recently approved, pan-genotypic, direct-acting antiviral regimen, glecaprevir and pibrentasvir, may simplify prescribing. The simplicity of these new therapies, with few side effects, makes it possible for nephrologists to treat HCV infection in their patients on dialysis. We review the workflow and motivation behind nephrology-led management of HCV infection. We highlight the importance of identifying which patients need referral to a hepatologist or HCV specialist prior to treatment and which can be managed by their nephrologist. Nephrologist involvement would lead to improved access to treatment and ensure that appropriate patients are referred for HCV treatment. In this paper, we review the background of HCV infection, its effect on dialysis patients, and impact on kidney transplantation. In addition, we outline the therapy options for each genotype of HCV, and we discuss the benefits and barriers to nephrology-led HCV treatment.

Pegylated interferon monotherapy for hepatitis C virus infection in patients on hemodialysis: A single center study

There is no published study from India on hepatitis C virus (HCV) treatment in dialysis patients. Patients on dialysis with HCV infection treated with pegylated interferon (Peg-INF) monotherapy were studied. All patients were subjected to HCV-polymerase chain reaction, viral load, genotype, and liver biopsy. Quantitative HCV-RNA was performed monthly. Patients with genotype 1 and 4 were given 12 month therapy while those with genotypes 2 and 3 were given 6 months therapy. Response was classified as per standard criteria of rapid virological response (RVR), early virological response (EVR), end of treatment response (ETR), and sustained virological response (SVR). A total of 85 patients were treated. Mean age was 35.2 ± 10.5 (range 15-67) years, and 77.6% were males. HCV genotypes were 1 in 40.9%, 2 in 12%, 3 in 36.1%, 4 in 3.6%, and others in 7.2%. Mean viral load was 10(6) copies/mL. Mean liver biopsy grade was 4 ± 1.7 and stage 0.8 ± 0.8. Mean time from diagnosis of HCV infection and the treatment start was 10.7 ± 14.3 months. One patient died of unrelated illness, one was lost to follow-up, and three could not sustain treatment due to cost. Forty-three of the 80 (54%) patients had RVR while 49 (61%) patients had EVR and ETR. There was no difference in term of RVR related to genotype. Fifty -four percentage had SVR. Mild flu-like symptoms were seen in all patients. Sixty-four (80%) patients required increase in erythropoietin doses. Twenty-eight (35%) patients developed leukopenia (three treatment-limiting) and 16 (20%) developed thrombocytopenia (one treatment-limiting). Five patients developed tuberculosis, five bacterial pneumonia, and one bacterial knee monoarthritis. None of the patients developed depression. Our study concludes that Peg-INF monotherapy resulted in 54% RVR and SVR in dialysis patients with HCV infection. Therapy was well-tolerated with minimal side effects. There was no effect of viral genotype on response to therapy.

[Management of hepatitis B virus and hepatitis C virus infection in chronic kidney failure]

Chronic infections by hepatitis B (HBV) and C virus (HCV) result in diagnosis and therapeutic issues in dialysis and kidney recipients patients. The exposure to nosocomial, including blood transfusion, risk explains the high prevalence of HBV and HCV infection in this setting. Chronic infection reduces the survival of both patients and allografts, including a specific risk of de novo glomerulonephritis. Cirrhosis was considered as a contra-indication to renal transplantation given the high risk of decompensation and death, questionning the indication of a combined liver and kidney transplantation. Thus, it is mandatory to screen HBV and HCV markers in all dialysis patients, whether or not they are candidates to transplantation. Liver biopsy allows evaluating the severity of the liver disease since the noninvasive markers of fibrosis appear to be less accurate in "renal" patients than in the general population and to better define antiviral therapeutic indications. HCV treatment was mainly based on pegylated interferon α (and low doses of ribavirin), which is contra-indicated in kidney recipients given the risk of graft rejection; HCV treatment is now based on the use of oral direct acting antivirals, which are very potent and well tolerated. HBV replication is now easily suppressed by second-generation nucleos(t)tidic analogues (entecavir and tenofovir), which will be indicated in all the dialysis patients with significant fibrosis (F2,3 or 4 according to the Metavir scoring system) and in any candidate to renal transplantation and to any HBsAg-positive kidney recipients. The best treatment remains preventive by anti-HBV vaccination for HBV and by the respect of universal hygiene rules for HCV.

Hepatitis C virus infection in hemodialysis patients

Hepatitis C virus (HCV) infection is observed in around 20% of dialysis patients and in allograft recipients and results in a significant morbidity and mortality, especially after transplantation. Its prevalence has markedly decreased in patients who are candidates for transplantation since the introduction of screening, hygiene and prevention measures, including systematic screening of blood and organ donations, use of erythropoietin, and compliance with universal hygiene rules. A liver biopsy is preferable to non-invasive biochemical and/or morphological tests of fibrosis to evaluate liver fibrosis before and even after transplantation. In HCV-infected dialyzed patients who are not candidates for renal transplantation, the indication for antiviral therapy is limited to significant fibrosis (fibrosis ≥ 2 on the METAVIR scale). Antiviral treatment should be proposed to any HCV-infected candidate for renal transplantation, whatever the baseline histopathology. The recommendation is to use standard interferon-α as monotherapy, but pegylated interferon can be used, resulting in sustained virological response, while low doses of combined ribavirin may enhance the antiviral efficacy. After transplantation, interferon-α is contra-indicated but may be used in patients for whom the benefits of antiviral treatment clearly outweigh the risks, especially that of allograft rejection. All cirrhotic patients should be screened for hepatocellular carcinoma, whose risk is enhanced by immunosuppressive regimens. Sustained suppression of necro-inflammation may result in the reversal of cirrhosis, which reduces liver-related morbidity and improves patient and allograft survival. Finally, due to the high mortality after renal transplantation, active cirrhosis must be considered to be a contraindication to kidney transplantation, but an indication to combined liver-kidney transplantation; on the contrary, inactive compensated cirrhosis may permit renal transplantation alone.

Hepatitis C virus infection and dialysis: 2012 update

Hepatitis C virus infection is still common among dialysis patients, but the natural history of HCV in this group is not completely understood. Recent evidence has been accumulated showing that anti-HCV positive serologic status is significantly associated with lower survival in dialysis population; an increased risk of liver and cardiovascular disease-related mortality compared with anti-HCV negative subjects has been found. According to a novel meta-analysis (fourteen studies including 145,608 unique patients), the adjusted RR for liver disease-related death and cardiovascular mortality was 3.82 (95% CI, 1.92; 7.61) and 1.26 (95% CI, 1.10; 1.45), respectively. It has been suggested that the decision to treat HCV in patients with chronic kidney disease be based on the potential benefits and risks of therapy, including life expectancy, candidacy for kidney transplant, and co-morbidities. According to recent guidelines, the antiviral treatment of choice in HCV-infected patients on dialysis is mono-therapy but fresh data suggest the use of modern antiviral approaches (i.e., pegylated interferon plus ribavirin). The summary estimate for sustained viral response and drop-out rate was 56% (95% CI, 28-84) and 25% (95% CI, 10-40) in a pooled analysis including 151 dialysis patients on combination antiviral therapy (conventional or pegylated interferon plus ribavirin).

Pharmacokinetic predictions for patients with renal impairment: focus on peptides and protein drugs

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• Renal impairment may affect the pharmacokinetics of peptide and protein drugs. • Molecular size is a predictor. Small molecules are eliminated by the kidneys, whereas large molecules (>67 kDa) are not. • Urinary recovery of peptide and protein drugs in healthy volunteers is not predictive for pharmacokinetic changes in patients with renal impairment.

WHAT THIS STUDY ADDS

• An apparently continuous non-linear relationship between molecular weight and pharmacokinetic alterations as observed in patients with severe renal impairment or end-stage renal disease is described. • Potentially relevant pharmacokinetic changes were found for drugs with a molecular weight below 50 kDa. • Analysis of observed pharmacokinetics in patients with severe renal impairment may be a useful approach, especially when urinary recovery in healthy volunteers is not predictive.

AIM

Drug dosage adjustments in renal impairment are usually based on estimated individual pharmacokinetics. The extent of pharmacokinetic changes in patients with renal impairment must be known for this estimation. If measured data are not available, an estimate based on drug elimination in urine of healthy subjects or patients with normal renal function is commonly made. This is not reliable, however, if renal drug metabolism is involved, as is presumably the case for many peptide and protein drugs. In the present study a new method to predict pharmacokinetic changes for such drugs based on molecular weight was derived.

METHODS

Articles reporting measured pharmacokinetics of peptide and protein drugs in patients with severe renal impairment or end-stage renal disease were identified from the scientific literature, the pharmacokinetic parameter values were extracted and a statistical data synthesis was performed. A sigmoid E(max) model was applied and fitted to the data and the prediction error was analyzed.

RESULTS

Overall, 98 peptide and protein drugs were identified. Relevant pharmacokinetic data in patients with renal impairment were found for 21 of these drugs. The average drug clearance was 30% and the average prolongation in half-life was 3.1-fold for low molecular weight peptides or proteins. The median root squared percentage of the prediction error was 18% (drug clearance) and 12% (half-life).

CONCLUSION

An apparently continuous non-linear relationship between molecular weight and pharmacokinetic alterations in patients with severe renal impairment was found. The derived equations could be used as a rough guide for decisions on drug dosage adjustments in such patients.

Viral hepatitis in solid organ transplantation other than liver

Transplantation is the best treatment for end-stage organ failure. Hepatitis virus infections, mainly hepatitis B virus (HBV) and hepatitis C virus (HCV) infections still constitute a major problem because they are common in allograft recipients and are a significant cause of morbidity and mortality after transplantation. Recently, hepatitis E virus infection has been added as an emergent cause of chronic hepatitis in organ transplantation. The prevalence of HBV and HCV infections has markedly decreased in patients who are candidates for transplantation since the introduction of screening, hygiene and prevention measures, including systematic screening of blood and organ donations, use of erythropoietin, compliance with universal hygiene rules, segregation of HBV-infected patients from non-infected patients and systematic vaccination against HBV. A liver biopsy is preferable to non-invasive biochemical and/or morphological tests of fibrosis to evaluate liver fibrosis before and even after transplantation. Treatment with entecavir or tenofovir is indicated in HBV-infected dialyzed patients who have moderate or severe disease (≥A2 or F2 on the Metavir scale) in preparation for renal transplantation. Due to the risks of severe reactivation, fibrosing cholestatic hepatitis or histological deterioration after transplantation, systematic use of nucleoside or nucleotide analogues shortly before or at the time of transplantation is recommended (tenofovir or entecavir are preferable to lamivudine) in all patients, whatever the baseline histological evaluation. In HCV-infected dialyzed patients who are not candidates for renal transplantation, the indication for antiviral therapy is limited to significant fibrosis (fibrosis ≥2 on the Metavir scale). Treatment must be proposed to all candidates for renal transplantation, whatever their baseline histopathology, and interferon-α should be used as monotherapy. After transplantation, interferon-α is contraindicated but may be used in patients for whom the benefits of antiviral treatment clearly outweigh the risks, especially that of allograft rejection. All cirrhotic patients, notably after solid organ transplantation, should be screened for hepatocellular carcinoma. Sustained suppression of necro-inflammation may result in regression of cirrhosis, which in turn may lead to decreased disease-related morbidity and improved survival. Finally, due to the high mortality after renal transplantation, active (namely without sustained viral suppression) cirrhosis should be considered a contraindication to kidney transplantation, but an indication to combined liver-kidney transplantation; on the contrary, inactive (namely with sustained viral suppression) compensated cirrhosis may permit renal transplantation alone. Organ transplantations other than kidney (cardiac or pulmonary transplantations) involve the same diagnosis and therapeutic issues.

Treatment of hepatitis C virus infection in patients with end-stage renal disease

Hepatitis C virus (HCV) infection is a major health problem in patients with end-stage renal disease (ESRD). The incidence of acute HCV infection during maintenance dialysis is much higher than that in the general population because of the risk of nosocomial transmission. Following acute HCV infection, most patients develop chronic HCV infection, and a significant proportion develop chronic hepatitis, cirrhosis, and even hepatocellular carcinoma. Overall, chronic hepatitis C patients on hemodialysis bear an increased risk of liver-related morbidity and mortality, either during dialysis or after renal transplantation. Interferon (IFN) therapy is modestly effective for the treatment of HCV infection in ESRD patients. Conventional or pegylated IFN monotherapy has been used to treat acute hepatitis C in ESRD patients with excellent safety and efficacy. Regarding chronic hepatitis C, approximately one-third of patients can achieve a sustained virological response (SVR) after conventional or pegylated IFN monotherapy. The combination of low-dose ribavirin and conventional or pegylated IFN has further improved the SVR rate in treatment-naïve or retreated ESRD patients in clinical trials. Similar to the treatment of patients with normal renal function, baseline and on-treatment HCV virokinetics are useful to guide optimized therapy in ESRD patients. Of particular note, IFN-based therapy is not recommended at the post-renal transplantation stage because of the low SVR rate and risk of acute graft rejection. In conclusion, ESRD patients with HCV infection should be encouraged to receive antiviral therapy, and those who achieve an SVR usually have long-term, durable, virological, biochemical, and histological responses.

Increased prevalence of reduced estimated glomerular filtration rate in chronic hepatitis C patients

BACKGROUND

To investigate the prevalence and severity of reduced estimated glomerular filtration rate (eGFR) in patients with chronic hepatitis C (CHC).

METHODS

Medical record review of 831 consecutive CHC patients seen in our clinic between July 2000 and August 2003; eGFR was estimated using the abbreviated Modification of Diet in Renal Disease (aMDRD) equation. The stage of kidney disease was determined based on eGFR expressed in milliliters per minute per 1.73 m(2): stage 1 (signs of kidney damage but normal or elevated (eGFR >or= 90), stage 2 (eGFR 60-89), stage 3 (30-59), stage 4 (eGFR 15-29), stage 5 (eGFR < 15 or dialysis-dependent).

RESULTS

A total of 522 patients had available data with using the aMDRD equation, 51% had abnormal eGFR (stage 1, 4.6%; stage 2, 36.4%; stage 3 or 4, 6.1%; stage 5, 3.8%). Of 190 patients with stage 2 kidney disease, 189 patients (99.5%) had normal serum creatinine and only one patient (0.5%) had elevated creatinine concentrations (>1.4 mg/dl). Of the 32 patients with stage 3 or 4 disease, 20 (62.5%) had a normal serum creatinine concentration. Of 349 patients without diseases known to cause renal insufficiency, 38% had stage 2-4 renal disease. In a subset of these patients, 95/522 (18%) the measured creatinine clearance showed good correlation with their aMDRD (R = 0.47, (p < 0.0001).

CONCLUSIONS

In CHC patients, a normal serum creatinine concentration does not assure normal kidney function. Estimation of eGFR with the aMDRD equation is a more accurate method of identifying patients with chronic kidney disease and reduced eGFR. Therefore, CHC patients should be screened more rigorously for chronic kidney disease because of the high prevalence of reduced eGFR. Lastly, in all CHC patients, the aMDRD eGFR should be used in each encounter with these patients when assessing their renal function irrespective of their serum creatinine.

Interferon for hepatitis C virus in hemodialysis--an individual patient meta-analysis of factors associated with sustained virological response

BACKGROUND AND OBJECTIVES

Hepatitis C virus (HCV) infection is prevalent in hemodialysis patients and causes excess mortality. Interferon (IFN) treatment of chronic HCV infection in hemodialysis patients results in high sustained virological response (SVR) rates 6 mo after treatment. The authors aimed to identify factors associated with SVR in hemodialysis patients through analysis of individual patient data obtained from systematic review of published literature.

DESIGN, SETTING, PARTICIPANTS & MEASUREMENTS

Medline was searched from 1966 through February 2009, and prospective studies describing IFN treatment of hemodialysis patients with chronic HCV infection with published individual patient data were included. To identify factors associated with SVR, logistic regression was applied with adjustment for study.

RESULTS

Twenty studies of IFN treatment provided data on 428 patients. Overall SVR was 45% and in univariate analyses was higher with: 1) three million units or higher three times weekly of IFN; 2) treatment for at least 6 mo; 3) treatment completion; 4) lower baseline HCV RNA; 5) female gender; and 6) early virological negativity. Although limited by missing data, these relationships persisted in multivariate regression.

CONCLUSIONS

SVR is more likely with larger IFN dose, longer treatment duration, treatment completion, female gender, lower HCV RNA and early virological negativity. For appropriate treatment candidates, regimens should consist of three million units of IFN three times weekly for at least 6 mo, with patients encouraged to complete the full course.

Hepatitis C virus and kidney disease

Hepatitis C virus (HCV) infection remains frequent in patients on renal replacement therapy and has an adverse impact on survival in infected patients on chronic hemodialysis as well as renal transplant (RT) recipients. Nosocomial spread of HCV within dialysis units continues to occur. HCV is also implicated in the pathogenesis of renal dysfunction often mediated by cryoglobulins leading to chronic kidney disease as well as impairing renal allograft function. The role of antiviral therapy for hepatitis C in patients with renal failure remains unclear. Monotherapy with conventional interferon (IFN) for chronic hepatitis C is probably more effective in dialysis than in non-uraemic patients but tolerance is lower. Limited data only are available about monotherapy with pegylated interferon and combination therapy (pegylated IFN plus ribavirin) for chronic HCV in the dialysis population. Clinical experience with antiviral therapy for acute HCV in dialysis population is encouraging. Interferon remains contraindicated post-RT because of concerns about precipitating graft dysfunction. Sustained viral responses obtained by antiviral therapy in renal transplant candidates are durable after renal transplantation and may reduce HCV-related complications after RT (post-transplant diabetes mellitus, HCV-related glomerulonephritis, and chronic allograft nephropathy).

HCV in patients with end-stage renal disease

Chronic hepatitis C virus (HCV) infection remains an important cause of liver disease in patients with end-stage renal disease (ESRD) and conversely, renal failure has a significant impact on morbidity and mortality throughout the natural history of chronic HCV and its treatment. With improved awareness within dialysis units of the potential for spread and the institution of preventative measures, the prevalence of HCV infection in the hemodialysis-dependent population has continued to decline since 1995. Use of HCV (+) donor kidneys is associated with an increase in the prevalence of liver disease, but when compared with continued hemodialysis, transplantation using these kidneys is associated with improved survival. Overall, survival in patients with chronic HCV infection appears to be better after renal transplantation when compared with maintenance hemodialysis, and transplant should be considered for these patients. Data support the use of interferon and the improved efficacy of pegylated interferon formulations for treatment of chronic HCV infection in ESRD patients, although tolerability continues to be troublesome. The newest and most promising data regarding the treatment of HCV in ESRD involve the combination of reduced dose ribavirin with interferon or pegylated interferon suggesting similar enhancements in sustained virologic response (SVR) as seen in non-ESRD patients, but caution is advised, as all studies to date used ribavirin plasma concentration monitoring in patient with ESRD. Finally, with regard to postrenal transplant treatment of HCV infection, there is no evidence to support treatment with interferon-based therapy and pretransplant treatment remains the best option whenever possible.

Antiviral therapy of hepatitis C in chronic kidney diseases: meta-analysis of controlled clinical trials

Hepatitis C virus (HCV) infection remains frequent in patients with chronic kidney disease and the detrimental role of HCV on survival is well-established in this population. Several authors have reported on efficacy and safety of antiviral therapy for hepatitis C in this polulation but there is no clear consensus on management. To evaluate efficacy and safety of antiviral therapy for hepatitis C in patients with chronic kidney disease, we performed a systematic review of the published medical literature and completed a meta-analysis of controlled clinical trials. The primary outcome was sustained virological response (as a measure of efficacy); the secondary outcome was drop-out rate (as a measure of tolerability). We used the random effects model of Der Simonian and Laird, with heterogeneity and sensitivity analyses. We identified 13 studies including 539 unique patients; 10 (76.9%) concerned patients on maintenance dialysis. Only prospective, controlled clinical trials were included. Pooling of study results showed a significant increase of viral response in study (patients treated with antiviral therapy) than control patients (patients who did not receive therapy), the pooled odds ratio (OR) of failure to obtain a sustained viral response was 0.081 [95% confidence intervals (CI), 0.029-0.230], P = 0.0001. The pooled OR of drop-out rate was significantly increased in study vs control patients, OR = 0.389 (95% CI, 0.155-0.957), P = 0.04. The studies were heterogeneous with regard to viral response and drop-out rate. In the subset of clinical trials (n = 6) involving only dialysis patients receiving interferon (IFN) monotherapy for chronic HCV, there was a significant difference in the risk of failure to obtain a sustained viral response (study vs control patients), OR = 0.054 (95% CI, 0.019; 0.150), P = 0.0001 (random-effects model). No significant (NS) heterogeneity was found (Q = 14.604, P = 1.0). No difference in the drop-out rate between study and control patients was shown, OR = 0.920 (95% CI, 0.367; 2.311), NS. This result being homogeneous (Q = 3.639, P = 0.388). Our meta-analysis showed that the viral response was greater in patients with chronic kidney disease who received antiviral therapy than controls. No difference in the drop-out rate between study and control patients occurred in the subgroup of dialysis patients on IFN monotherapy. These results support IFN-based therapy for hepatitis C in patients on maintenance dialysis.

[Chronic viral hepatitis and kidney failure]

Chronic viral hepatitis remains a major problem among patients with chronic renal failure. Hepatitis B and C viruses are frequent among dialysis patients and after renal transplantation and may significantly diminish the survival of both the patient and the graft. Hepatitis B and C viral infection in these patients is often characterized by normal transaminase levels despite viremia and progressive liver lesions. Liver biopsy remains essential for assessing the extent of liver disease. Cirrhosis is a contraindication to transplantation of only a kidney, because of elevated morbidity and mortality. A combined as liver-kidney transplantation may be considered. The best treatment of hepatitis infections is preventive: vaccination against the hepatitis B virus and attentive hygiene, especially to prevent nosocomial transmission. Among patients not awaiting transplant, antiviral treatment should be reserved for patients with active or even fibrotic liver disease. For hemodialysis patients awaiting kidney transplant: Alpha interferon is ineffective and poorly tolerated by dialysis patients. Lamivudine is effective and well tolerated, but its long-term efficacy and its optimal effective dose in dialysis patients remain unknown.

Interferon treatment in hemodialysis patients with chronic hepatitis C virus infection: a systematic review of the literature and meta-analysis of treatment efficacy and harms

BACKGROUND

Hepatitis C virus (HCV) infection is prevalent in patients undergoing hemodialysis and is associated with greater mortality. We determined the efficacy and harms of interferon (IFN) and pegylated IFN (PEG-IFN) treatment of hemodialysis patients with chronic HCV infection and identified factors associated with these outcomes.

STUDY DESIGN

Meta-analysis and meta-regression of randomized controlled trials, uncontrolled trials, and prospective observational studies.

SETTING & POPULATION

Hemodialysis patients with chronic HCV infection.

SELECTION CRITERIA FOR STUDIES

MEDLINE indexed studies since 1966, sample size greater than 10.

INTERVENTION

IFN-based treatment, including PEG-IFN with and without ribavirin.

OUTCOMES

Sustained virological response (SVR) 6 months after treatment, rate of treatment discontinuation caused by adverse events, and factors associated with these outcomes.

RESULTS

20 studies of 459 IFN-treated patients, 3 studies of 38 PEG-IFN-treated patients, and 2 studies of 49 PEG-IFN and ribavirin-treated patients met inclusion criteria. The overall SVR rate was 41% (95% confidence interval [CI], 33 to 49) for IFN and 37% (95% CI, 9 to 77) for PEG-IFN. Treatment discontinuation rates were 26% (95% CI, 20 to 34) for IFN and 28% (95% CI, 12 to 53) for PEG-IFN. SVR was higher with 3 million units (MU) or higher of IFN 3 times weekly, with lower mean HCV RNA, and with lower rates of cirrhosis, HCV genotype 1 or elevated transaminase, but these findings were not statistically significant. Treatment discontinuation rates were greater in studies using larger doses.

LIMITATIONS

Publication bias, few randomized controlled trials, and limitations in generalizability to all hemodialysis patients.

CONCLUSION

IFN treatment of hemodialysis patients results in an SVR rate of 41%. Higher dose, lower mean HCV RNA level, and lower rates of cirrhosis, transaminase level increase, and HCV genotype 1 may be associated with greater SVR rates, but additional studies using individual patient data are needed.

Interferon monotherapy of chronic hepatitis C in dialysis patients: meta-analysis of clinical trials

The efficacy of monotherapy with interferon (IFN) (conventional or pegylated IFN) in dialysis patients with chronic hepatitis C remains unclear, although a number of clinical trials have been published addressing this issue. The aim of the study was to evaluate the efficacy and safety of monotherapy by conventional or pegylated IFN in dialysis patients with chronic hepatitis C by performing a systematic review of the literature with a meta-analysis of clinical trials. The primary outcome was sustained virological response (SVR; as a measure of efficacy), and the secondary outcome was drop-out rate (as a measure of tolerability). We used the random-effects model of Der Simonian and Laird, with heterogeneity and sensitivity analyses. We identified 28 clinical trials (645 unique patients), of which six (21.4%) had a controlled design. In the group of trials based on conventional IFN, the summary estimate for SVR and drop-out rate was 39% [95% confidence interval (CI) 32-46] and 19% (95% CI 13-26) respectively. The summary estimate for SVR rate in patients with the hepatitis C virus genotype 1 was 33% (95% CI 19-47). In the subset of trials using pegylated IFN, the summary estimate for SVR and drop-out rate was 31% (95% CI 7-55) and 27% (95% CI 1-52) respectively. The most frequent side-effects requiring interruption of treatment were flu-like symptoms, and gastrointestinal and haematological changes. A relationship between age and drop-out rate was found, even if no statistical significance was reached (P = 0.064). The studies were heterogeneous with regard to SVR and drop-out rate. No publication bias was observed. One-third of dialysis patients with chronic hepatitis C were successfully treated with conventional or pegylated IFN monotherapy. Preliminary evidence does not support additional benefit due to monotherapy with pegylated IFN on the viral response in the chronic kidney disease (CKD) population. Tolerance to IFN monotherapy was unsatisfactory, particularly to pegylated IFN. The optimal antiviral treatment of chronic hepatitis C in dialysis populations is currently under active investigation.

Chronic hepatitis C virus infection in renal transplant: treatment and outcome

BACKGROUND

Chronic hepatitis C virus (HCV) infection is a common cause of liver disease in post-renal transplant period and causes poor patient and graft survival. We analyzed the effects of antiviral therapy using ribavirin monotherapy or ribavirin in combination with interferon (IFN)-alpha in our kidney transplant recipients with chronic hepatitis C.

METHODS

Total of 14 patients received antiviral therapy, all of whom had stable graft function, raised aminotransferases and positive HCV viremia at the start of treatment. Eight patients received ribavirin alone for a period of six months to two yr, in doses of 400-800 mg daily. Five patients received IFN-alpha therapy for a period of two months to 1.5 yr, in doses of 1.5 million units daily or three million units thrice weekly with ribavirin. One patient received pegylated IFN 50 microg once weekly in combination with ribavirin. The response was seen in terms of biochemical and virological improvement at the end of study period.

RESULTS

In patients treated with ribavirin alone (n = 8), mean alanine aminotransferase (ALT) levels before and after treatment were significantly different (198.4 +/- 147.6 and 104.8 +/- 66.5 IU/L respectively; p < 0.05). ALT levels normalized completely in three patients at the end of treatment, improved in three patients and deteriorated in two. Only in one of eight patients on ribavirin alone, HCV-RNA became negative after six months of treatment while in the rest (n = 7) HCV-RNA continued to be positive. In subjects on IFN plus ribavirin (n = 6), the mean ALT levels decreased significantly (from 280.2 +/- 114.9 IU/L at baseline to 71 +/- 49 IU/L at end of therapy; p < 0.05). Two patients had sustained remission (33.3%) on IFN plus ribavirin (persistently negative HCV-RNA), two patients relapsed after initial remission and in two patients treatment was stopped after two months because of graft dysfunction. Totally four patients developed graft dysfunction at some time during the course of IFN therapy (66.6%), but it was discontinued in only two (33.3%). All patients regained normal creatinine levels after discontinuation of IFN, although one patient developed chronic allograft nephropathy as shown by kidney biopsy. Four patients in IFN group developed leucopenia. Two patients developed severe anemia one of whom required blood transfusion and one developed severe flu-like syndrome requiring stoppage of therapy.

CONCLUSION

Ribavirin monotherapy in renal transplant recipients with chronic hepatitis C infection results in good biochemical response but is not associated with virological clearance. IFN in combination with ribavirin is effective in two-thirds of patients after a minimum therapy of six months, but it is poorly tolerated, results in graft dysfunction in significant number of patients, and relapse can occur after stopping treatment.

Efficacy of Interferon-α in the Treatment of Chronic Hepatitis C in Dialysis Patients: Two Therapeutic Protocols Compared

BACKGROUND

Data on the efficacy of particular therapeutic protocols of interferon-alpha (IFN-alpha) treatment for chronic hepatitis C in patients on hemodialysis (HD) vary.

AIM

To compare the efficacy of two different therapeutic protocols for HD patients.

PATIENTS AND METHODS

15 hepatitis C virus (HCV)-positive patients on chronic HD at two dialysis centers: 8 patients treated with IFN-alpha 3 x 3 MU/week s.c. for 6 months (group A), and 7 patients treated with IFN-alpha 3 x 5 MU/week for 3 months, then 1 x 5 MU/week for another 3 months (group B). End of treatment response (ETR) and sustained virologic response (SVR) were evaluated by HCV-RNA determination. There was no statistically significant difference between the two patient groups according to age, sex, duration of HD and HCV infection.

RESULTS

ETR was 87.5% (7/8) in group A and 28.5% (2/7) in group B, being statistically significant (p < 0.05). Although better SVR [50% (4/8) vs. 28.5% (2/7)] and lower drop-out rate [0% (0/8) vs. 28.5% (2/7)] were achieved in group A compared to group B, these differences did not reach statistical significance (p > 0.05).

CONCLUSION

Therapy with IFN-alpha 3 x 3 MU/week s.c. for 6 months seems to be more appropriate for treatment of hepatitis C in HD patients, mostly due to better tolerability, i.e. lower drop-out rate. These differences could be attributed to different pharmacokinetic properties of the particular therapy protocol.

Treatment of chronic hepatitis C in patients with end-stage renal disease and hemophilia--the Singapore experience

OBJECTIVE

The aim of this study was to determine the response to treatment with interferon-alpha (IFN-alpha) in patients with chronic hepatitis C who had end-stage renal disease (ESRD) or hemophilia in Singapore.

METHODS

Treatment-naive hepatitis patients with ESRD or hemophilia were given IFN-alpha(2a) 3 million units three times per week for 12 months in an open-label study. Hepatitis C virus RNA was determined before treatment, at the end of treatment and 6 months thereafter. Regular clinical examinations including blood counts and biochemistry were carried out during and after the treatment.

RESULTS

Nine consecutive patients with ESRD (8 men and 1 woman) and 6 consecutive male patients with hemophilia, with a mean age of 43 and 40 years, received treatment. Patients in both groups were predominantly infected with hepatitis C virus genotype 1 and had significant cytopenia affecting all three cell lines during the treatment; only 1 patient developed serious neutropenia, temporarily demanding a reduction of his IFN dose. Biochemical and virological responses at the end of treatment were accomplished by 8 of the 9 (89%) patients with ESRD and 4 of the 6 (67%) patients with hemophilia; however, 1 patient with ESRD and 2 with hemophilia relapsed after the treatment. Four of the 7 patients with ESRD who had sustained virological response underwent successful kidney transplantation later on.

CONCLUSION

Monotherapy with IFN-alpha for 12 months is safe for treatment of the patients with chronic hepatitis C who had ESRD or those with hemophilia. A higher sustained virological response rate was observed in patients with ESRD than in those with hemophilia (78 vs. 33%).

Treatment of hepatitis C in potential kidney and heart transplant patients

Hepatitis C virus (HCV) is common in certain solid organ transplant recipients, most notably in those undergoing liver or kidney transplantation. Infection typically antedates transplantation but may have been acquired at the time of transplantation via infected blood products or organs. A more rapid and aggressive course of HCV-related infection and liver disease is the major concern in organ transplant recipients compared with immunocompetent patients. HCV-related liver disease is an important cause of morbidity and mortality in patients with end-stage renal disease treated by dialysis or transplantation. The outcome of HCV infection in renal and liver transplant recipients has been extensively investigated, whereas literature on HCV-related liver disease among patients with orthotopic heart transplantation is scanty. This article reviews the literature concerning the treatment of HCV-related liver disease in renal and orthotopic heart transplantation.

Should patients with chronic hepatitis C infection be transplanted?

Chronic hepatitis C (HCV) infection affects more than 170 million people throughout the world and 2 to 3 million Americans. End-stage liver disease secondary to chronic HCV infection is the most frequent indication for liver transplantation in this country. Currently, the gold standard for treatment for immunocompetent patients is a combination of peginterferon (PEG-IFN) and ribavirin for 6 to 12 months depending on the genotype. This treatment achieves a sustained virological response (SVR) in 54% to 61% of patients overall. Almost 50% of patients do not respond or have recurrences posttreatment and progress in over 10 to 20 years into chronic liver disease and its complications. Liver transplantation is the only therapeutic modality that impacts on quality of life and survival of these patients. However, recurrence of HCV in the new allograft is universal with accelerated progression to cirrhosis in 5 to 10 years. Response to treatment is usually low (20% to 30%), and associated with significant side effects and depression. A significant percentage of patients with recurrent HCV after transplantation require retransplantation to control the complications of end-stage liver disease. Other solid organ transplants recipients already HCV-positive, or infected at the time of transplantation from blood transfusions or an infected graft, develop accelerated, progressive liver disease facilitated by the adverse effects of immunosuppression in addition to HCV replication. To prevent morbidity, mortality, and high costs related to the consequences of HCV infection, all solid organ transplant candidates should be tested for HCV infection and treated appropriately with PEG-IFN and ribavirin prior to transplantation.

Histopathologic efficacy of ribavirin monotherapy in kidney allograft recipients with chronic hepatitis C

BACKGROUND

The deterioration of chronic hepatitis C is frequent in kidney recipients and results in a decrease in survival of patients and allografts. Interferon is contraindicated because of the risk of rejection and its low efficacy. The aim of this study was to analyze the biologic, virologic, and histopathologic efficacy of ribavirin alone in kidney allograft recipients with hepatitis C.

METHODS

Thirteen kidney recipients (eight men and five women, 46+/-11 years of age) with severe Metavir score of fibrosis (eight F3 and five F4) were treated with ribavirin alone during 22.4+/-13.9 months. Liver biopsy was performed before and during therapy, with a mean interval time of 5.7+/-9.3 years.

RESULTS

The transaminase level decreased significantly (128+/-77 vs. 53+/-28, P=0.001) without significant change of serum quantitative hepatitis C virus load. The comparison of pretreatment and on-treatment biopsy specimens showed a significant decrease in the activity Metavir score (1.23+/-1.01 vs. 2.46+/-0.78, P=0.05) and a nonsignificant trend for a decrease in the fibrosis score. Ribavirin tolerance was fair, and only one patient required erythropoietin therapy.

CONCLUSIONS

Ribavirin alone in kidney allograft recipients results in biologic and histologic improvement without a virologic response and is reasonably well tolerated.

Renal transplant recipient with chronic hepatitis C who obtained sustained viral response after interferon-beta therapy

A 44-year-old Japanese woman with a history of living-related renal transplantation was treated with interferon-beta (IFN-beta) for chronic infection with sero-group 2 hepatitis C virus (HCV). Serum HCV-RNA titer was 160 kilo-international units/ml. Treatment with intravenous IFN-beta daily was given for 6 weeks. Serum HCV-RNA was undetectable at 3 weeks after initiating therapy. Renal graft rejection did not occur. Six months after completing therapy, she obtained sustained viral response. This case demonstrates that IFN-beta therapy safely induced clearance of HCV in a renal transplant recipient with stable renal function, low viral load and/or HCV sero-group 2.

Improved detection of HCV Infection in hemodialysis patients using a new HCV RNA qualitative assay: experience of a transplant center

BACKGROUND

Hepatitis C virus (HCV) is frequently a silent infection in hemodialysis (HD) patients with a prevalence of 8-10%. Improving HCV detection in this population prior to transplantation is critical both for infection control and optimal patient care.

OBJECTIVES

To assess the current HCV testing practice of the National Institute for Transplantation (PCR testing of enzyme immunoassay (EIA) positive HD patients) by evaluating a subset of EIA positive and EIA negative samples with the VERSANT HCV RNA Qualitative Assay based on transcription mediated amplification (HCV Qual (TMA)) (sensitivity < or = 9.6 IU/ml) and in-house PCR (HCV Qual (PCR)) (sensitivity approximately 149 IU/ml).

STUDY DESIGN

2321 HD patients were screened by Abbott HCV EIA 2.0. A subset of 80/169 E IA positive samples and 100/2152 EIA negative samples were tested by both assays. TMA/PCR discordant samples were genotyped.

RESULTS

PCR and TMA gave concordant results in 67/80 (83.8%) of EIA positive samples. 11/80 (14.7%) were reactive by HCV Qual (TMA), but not by HCV Qual (PCR); 2/80 (2.7%) were reactive by HCV Qual (PCR), but not by HCV Qual (TMA). 2/100 (2%) EIA negative samples were reactive and 95/100 (95%) were non-reactive by both assays. Three (3%) were only HCV Qual (TMA) reactive. 11/14 TMA+/PCR-samples with sufficient volume were genotyped.

CONCLUSIONS

HCV Qual (TMA) identified active HCV infection in more EIA positive and EIA negative patients than HCV Qual (PCR) and should be part of our testing algorithm.

Hepatitis C and renal disease: an update

Hepatitis C is both a cause and a complication of chronic renal disease. Chronic infection with hepatitis C virus (HCV) can lead to the immune complex syndromes of cryoglobulinemia and membranoproliferative glomerulonephritis (MPGN). The pathogenetic mechanisms for these conditions have not been defined, although they are clearly caused by the chronic viral infection. Management of HCV-related cryoglobulinemia and MPGN is difficult; antiviral therapy is effective in clearing HCV infection in a proportion of patients, but these conditions can be severe and resistant to antiviral therapy. Hepatitis C also is a complicating factor among patients with end-stage renal disease and renal transplants. The source of HCV infection in these patients can be nosocomial. Screening and careful attention to infection control precautions are mandatory for dialysis units to prevent the spread of hepatitis C. Prevention of spread is particularly important in these patients because HCV infection is associated with significant worsening of survival on dialysis therapy, as well as after kidney transplantation. Furthermore, therapy for hepatitis C is problematic, only partially effective, and associated with significant side effects in this population. There are significant needs in both basic and clinical research in the pathogenesis, natural history, prevention, and therapy for hepatitis C in patients with renal disease.

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.

Meta-analysis: interferon for the treatment of chronic hepatitis C in dialysis patients

BACKGROUND

The efficacy of interferon monotherapy in dialysis patients with chronic hepatitis C remains unclear, although a number of small clinical trials have been published addressing this issue.

METHODS AND AIMS

We evaluated the efficacy and safety of initial interferon monotherapy in dialysis patients with chronic hepatitis C by performing a systematic review of the literature with a meta-analysis of clinical trials. The primary outcome was sustained virological response (as a measure of efficacy); the secondary outcome was drop-out rate (as a measure of tolerability). We used the random effects model of Der Simonian and Laird, with heterogeneity and sensitivity analyses.

RESULTS

We have identified 14 clinical trials (269 unique patients); two were controlled studies. The mean overall estimate for sustained virological response (SVR) and drop-out rate was 37%[95% confidence interval (CI) 28-48] and 17% (95% CI 10-28), respectively. The most frequent side-effects requiring interruption of treatment were flu-like symptoms (17%), neurological (21%) and gastrointestinal (18%). The overall weighted estimate for SVR in patients with hepatitis C virus genotype 1 was 30.6% (95% CI 20.9-48). In the sub-group of clinical trials (n = 5) with standard interferon administration (3 million units [MUI] thrice weekly, subcutaneous route, 24-week treatment), the overall mean estimate of SVR was 39% (95% CI 25-56). The studies were heterogeneous with regard to SVR and drop-out rate.

CONCLUSIONS

Tolerance to initial interferon monotherapy was lower in dialysis than nonuremic patients with chronic hepatitis C. However, more than one-third of haemodialysis patients with chronic hepatitis C have been successfully treated with interferon. Longer duration of interferon monotherapy does not appear to have a beneficial effect on the response rate. Further studies are warranted to define the optimal anti-viral regimen for chronic hepatitis C in dialysis population.