Interferon treatment for hepatitis C virus infection in patients on haemodialysis

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.

Long-term viral negativity after interferon for chronic hepatitis C virus infection in hemodialysis

BACKGROUND AND OBJECTIVES

Interferon (IFN) and pegylated-IFN treatment of hepatitis C virus (HCV) infection in hemodialysis patients result in sustained virological response (SVR) rates of 45% and 37%, respectively. Although most nonhemodialysis patients who achieve SVR remain persistently viral negative, the durability of SVR in hemodialysis patients is unknown. We analyzed the rate of long-term virological negativity in hemodialysis patients who achieved SVR after IFN or pegylated-IFN through analysis of patient-level data.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

After performing a systematic literature review for IFN-based treatment of hemodialysis patients with chronic HCV infection, we extracted patient-level data on patients who achieved SVR. We performed life table analysis to estimate long-term virological negativity rates after SVR in patients who continued on hemodialysis or subsequently underwent kidney transplantation.

RESULTS

Long-term HCV RNA outcomes following SVR were available for 121 hemodialysis patients (20 studies) and 45 patients who subsequently underwent transplantation (11 studies). The probability of remaining HCV RNA negative was 86% (95% confidence interval, 77% to 96%) for patients followed on hemodialysis 48 months after SVR and 95% (95% confidence interval, 89% to 100%) for kidney recipients followed 48 months after transplant.

CONCLUSIONS

Viral negativity from IFN-based HCV treatment in hemodialysis patient appears durable during extended follow-up, including after kidney transplantation. The certainty of the viral negativity estimate is limited by the small number with follow-up beyond 48 months or longer. Transplantation does not confer an increased risk of relapse. Future research should investigate whether IFN-based treatment improves clinical outcomes for hemodialysis patients.

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.

Hepatitis C and kidney disease

Multiple extrahepatic manifestations have been associated with chronic hepatitis C, the most important among them being cryoglobulinemia, glomerulonephritis, porphyria cutanea tarda, lichen planus, seronegative arthritis, and lymphoproliferative disorders as in the sudies of Bonkovsky and Mehta (2001) and El-Serag et al. (2002). We will discuss in this paper chronic hepatitis C- related kidney disease and course and management of patients with chronic hepatitis C in special circumstances like hemodialysis and kidney transplantation.

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.

A Six‐Year Follow‐Up After Interferon‐Alpha Monotherapy for Chronic Hepatitis C Infection in Hemodialysis Patients

Interferon-alpha (IFN) has been accepted as an effective treatment for chronic hepatitis C virus (HCV) infection in hemodialysis (HD) patients. We prospectively assess the long-term clinical, biochemical, and virological effects of interferon in the treatment of HD patients with chronic HCV infection. This study was performed in 20 HCV-RNA-positive HD patients with evidence of chronic hepatitis on liver biopsy. The patients received IFN administered after HD sessions in doses ranging from 3 to 6 million units for 6 to 12 months. The patients were followed up for a period of 6 years with determinations of serial alanine aminotransferase (ALT) levels and serum HCV-RNA. At the time of the final follow-up, the patients had no cirrhosis or hepatocellular carcinoma. Among the nonresponder group, only 1 patient died due to sudden cardiac death. Sustained normal serum ALT levels occurred in 9 (45%) of the patients. Nine patients had variable ALT levels, and 2 patients had persistently elevated ALT levels. Eight (40%) patients were continuously HCV-RNA negative, whereas 12 patients (60%) had variable HCV-RNA results at the end of the 6-year follow-up. These findings show that the long-term clinical, biochemical, and virological response to interferon monotherapy is good in HD patients with HCV infection.

Treatment of chronic hepatitis C in hemodialysis patients

Hepatitis C virus (HCV) infection is especially problematic in patients with end-stage renal disease (ESRD) who are undergoing hemodialysis. Rates of HCV infection are higher among hemodialysis patients than in the general population, and several routes of transmission are thought to stem from the dialysis unit. Management of chronic hepatitis C is also more complicated in hemodialysis patients because of altered pharmacokinetics and a predisposition for drug-related toxicity, particularly ribavirin-induced anemia. Clinical trials of patients with chronic hepatitis C and healthy, functioning kidney grafts are rare because of the inherent dangers of graft rejection. As a result, most studies in patients with ESRD have focused on patients waiting for a kidney transplant. Additionally, because ribavirin is contraindicated in this patient population, many studies have examined monotherapy treatments. According to meta-analyses, conventional interferon alfa treatment yields a sustained virological response (SVR) rate of 37%, whereas studies of pegylated interferon alfa monotherapy have yielded SVR rates between 13% and 75%. Several small studies have also used the monitoring of ribavirin plasma concentrations or hemoglobin levels to facilitate the use of combination therapy. In light of the results from these clinical trials, we herein review treatment guidelines and recommend strategies to help optimize the treatment of patients with ESRD.

CONCLUSION

There remains a lack of clarity surrounding the most effective treatment options for patients with chronic hepatitis C and ESRD. Treatment can be effective with many patients attaining SVR; however, unfavorable tolerability with interferon alfa-based therapy remains a concern and thus close supportive care should be aggressively pursued to help maintain adherence.

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.

[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.

Pilot study of pegylated interferon-alpha 2a in dialysis patients with chronic hepatitis C virus infection

AIM

Pegylated interferon (PEG-IFN) combined with ribavirin is recommended for the treatment of chronic hepatitis C virus (HCV) infection in patients without renal failure. The optimal treatment of hepatitis C in dialysis patients remains to be established. A high incidence of adverse effects has been observed with conventional interferon and PEG-IFN alpha-2b in dialysis patients.

METHODS

We conducted a prospective study to investigate the tolerability and efficacy of PEG-IFN alpha-2a (135 microg weekly for 48 weeks) in six dialysis patients with chronic HCV infection.

RESULTS

Two patients completed 48 weeks of treatment. Treatment was stopped in three patients (beyond 24 weeks) when they developed unrelated complications, and stopped in one patient due to failure of viral clearance. None required treatment discontinuation due to adverse effects, and PEG-IFN alpha-2a was subjectively well tolerated. Marrow suppression with mild anaemia, leucopenia, or thrombocytopenia remained common. Two patients (infected with genotypes 3a and 1b, respectively) had sustained virological response.

CONCLUSIONS

Results from this pilot study showed that PEG-IFN alpha-2a appeared relatively well tolerated in dialysis patients with chronic HCV infection, and about one-third of patients could achieve sustained virological response.

Leptin restores plasma cholesterol, glucose and weight loss induced by IFNalpha treatment

Leptin, an adipokine, a major regulator of food intake, was recently suggested to play a role in immune response. We previously showed that weight reduction following IFNalpha therapy is due, at least in part, to direct induction of adipose tissue apoptosis. We now studied the effect of leptin on IFNalpha treated adipocytes in vitro and in vivo. Diet induced obese C57/B6 mice were treated continually with recombinant (r) IFNalphaA/D + leptin (100 U/g body weight + 10 microg/day, respectably) or leptin (10 microg/day) alone for 8 days. Co-administration of IFNalphaA/D + leptin significantly reduced plasma cholesterol (P<0.001), glucose (P<0.007) and pro-apoptotic protein levels (P<0.05). Additionally, co-administration prevented loss of body weight due to adipocyte apoptosis. Thus, leptin co-administration with IFNalphaA/D decreases some of the side effects of IFNalpha administration such as weight loss, cholesterol and glucose levels.

Liver steatosis in hepatitis C positive hemodialysis patients and factors affecting IFN-2a treatment

OBJECTIVE

Hepatitis C virus (HCV) infection is endemic among hemodialysis (HD) patients. It is well known that HCV causes approximately 50% of hepatosteatosis in patients with normal renal function and that this rate is higher in patients infected with genotype 3. The aim of this study was to investigate the rate of steatosis, the regression in steatosis with interferon (IFN) treatment and factors affecting IFN treatment in hemodialysis patients with chronic hepatitis C (CHC).

MATERIAL AND METHODS

Thirty-seven HD patients with CHC were included in the study. All patients received hemodialysis treatment three times a week during the follow-up period. Patients were treated with 3 million units (MU) of IFN-alpha 2a monotherapy for at least 6 months. All patients were evaluated by liver biopsy before therapy and 16 were evaluated at 12-month follow-up.

RESULTS

Mean age of the 37 patients (23 M, 14 F) was 44+/-11.6 years and body mass index was 21.8+/-1.8 kg/m2. Twenty-eight of the patients included in the study (75.7%) were of genotype 1b. RNA response after treatment was 78.4% and sustained response after the follow-up period of 14.9+/-8 months was 54%. Total cholesterol values were directly proportional to RNA response (p<0.003) and inversely correlated with resistance to treatment (p<0.008). Triglyceride values were inversely correlated with resistance to treatment (p<0.041). At evaluation of steatosis scores in baseline liver biopsy, severe and mild to moderate steatosis was found in 3 (8.1%) and 16 (43.2%) patients, respectively. In 18 patients (48.7%) there was no steatosis. The rate of steatosis was found to be 44% in control biopsies. While there was no regression in the rates of steatosis (p=0.499), it was found that steatosis regressed after IFN treatment in two patients infected with genotype 3. No correlations were observed between HCV genotype, sustained response and liver steatosis.

CONCLUSIONS

Response and sustained response rates of HD patients with HCV in a Turkish population were found to be high after IFN monotherapy. With the exception of two patients infected with genotype 3a, the rate of liver steatosis was found to be high and did not change after IFN treatment in HD patients with CHC.

IFN-alpha induces apoptosis of adipose tissue cells

Interferon alpha (IFN-alpha) is produced in response to viral infections and used clinically in the therapy of a variety of cancers and viral infections. IFN-alpha treatment is often associated with severe weight reduction. To elucidate the mechanism of IFN-associated weight loss, we studied its effect on adipocytes in vitro and in vivo. Diet-induced obese (DIO) C57BL/6 mice were treated continuously for 8 days with human IFN-alpha A/D (100 U/g body weight) or with vehicle alone. The body weight and adipose cell size of IFN-alpha A/D-treated DIO mice were significantly lower (P<0.05 and P<0.001, respectively) as compared with those of control DIO mice. PI3K and Bcl-2 were down-regulated whereas Bax expression was elevated in adipose tissue following IFN treatment as compared to adipose tissue of control DIO mice. Treatment of differentiated 3T3-F442A adipocytes with IFN-alpha A/D (250 U/ml, 36 h) significantly increased the number of apoptotic cells from 15.8% in control cells to 56+/-6%. In conclusion, weight loss following IFN-alpha therapy is due at least in part to increased apoptosis of adipocytes.

Chronic viral hepatitis in hemodialysis patients

Ever since the first outbreaks of hepatitis in hemodialysis units in the late 1960s, a number of hepatotropic viruses transmitted by blood and other body fluids have been identified. This review summarizes the current state of knowledge regarding these blood-borne agents from an epidemiologic and preventive perspective. Data source and study selection were obtained from research and review articles related to the epidemiology of viral hepatitis in hemodialysis and indexed on Medline and Embase from 1965 to 2004. Hepatitis B virus (HBV) was the first significant hepatotropic virus to be identified in hemodialysis centers. HBV infection has been effectively controlled by active vaccination, screening of blood donors, the use of erythropoietin, and segregation of HBV carriers. To date, HBV remains an important cause of morbidity in endemic areas. Hepatitis delta virus is a defective virus that can only infect HBV-positive individuals. Hepatitis C virus is the most significant cause of non-A, non-B hepatitis and is mainly transmitted by blood transfusion. The introduction in 1990 of routine screening of blood donors for HCV contributed significantly to the control of HCV transmission. An effective HCV vaccine remains an unsolved challenge, however. Pegylation of interferon-alpha has made it possible to treat HCV-positive dialysis patients. Unexplained sporadic outbreaks of hepatitis by the mid-1990s prompted the discovery of hepatitis G virus and hepatitis GB virus C in 1995 and the TT virus in 1997. Although epidemiologic analyses revealed high prevalence rates of both viruses in the hemodialysis population, their exact role in liver disease has yet to be determined. The vigilant observation of guidelines on universal precaution and regular virologic testing are the cornerstones of the effective control of chronic hepatitis in the setting of hemodialysis.

Viral hepatitis C in Hong Kong

OBJECTIVE

Hepatitis C virus (HCV) infection can lead to serious liver disease. Its medico-socio-economic burden on society can be immense. This study investigates the epidemiology of HCV infection in Hong Kong.

METHODS

Data from the Department of Health, relevant publications from Medline search and data from two acute hospitals were reviewed.

RESULTS

The prevalence of anti-HCV among voluntary blood donors is stable, remaining at approximately 0.035-0.099% over the past 10 years, and is higher in the older age group. Among the high-risk groups, the anti-HCV prevalence is as follows: (1) hospital patients 0.8%, (2) intravenous drug users 46.0%, (3) patients infected with HIV 7.9%, (4) children with transfusion-dependent hematologic disease 16.3%, (5) patients on continuous ambulatory peritoneal dialysis 1.8%, patients on hemodialysis 16.4%, recipients of kidney transplants 6.2% and (6) patients with hepatocellular carcinoma 7.3%. Among blood donors, 58.8% were infected with HCV genotype 1b and 27.0% with genotype 6a. Genotype 6a is particularly common among intravenous drug users.

CONCLUSION

Hong Kong has a low prevalence of HCV infection. Patients are mostly infected through transfusion with blood or products prior to the introduction of anti-HCV screening to the blood transfusion service. Illicit drug use constitutes another significant risk. Since 1997, there has been a great increase in population movement between China and Hong Kong which might affect the epidemiology of HCV infection.

Hepatitis B virus infection in dialysis patients

Hepatitis B virus (HBV) infection remains a major issue among dialysis patients. It is associated with a high risk of hepatic complication. The liver disease runs a unique clinical course in dialysis patients, as it can progress with modest hepatic inflammation and prominent fibrosis. The conventional cut-off level of serum alanine aminotransferase (ALT) for commencing antiviral therapy may prove too high and inappropriate for dialysis patients, and liver biopsy appears to be the only definitive means to establish the activity of liver disease in dialysis patients. Liver biopsy should be considered in patients with a serum ALT level that is persistently greater than 30 IU/L, or 0.75-fold the upper limit of the normal level, and/or other clinical and laboratory findings that suggest active liver disease. For antiviral treatment, preliminary reports have shown that lamivudine is effective and well tolerated in dialysis patients. However, the long-term efficacy of lamivudine and its optimal effective dose in dialysis patients remain unknown. The prevention of nosocomial transmission among dialysis patients is also important. Universal precaution measures should be strictly observed and the segregation of hepatitis B surface antigen-positive hemodialysis patients should be considered. For HBV non-immune patients, the importance of HBV vaccination should not be overemphasized. Until a new generation of highly immunogenic vaccines that are proven to be safe and effective in patients with end-stage renal disease becomes available, early vaccination before the development of end-stage renal failure remains the best way to secure immunological protection against HBV infection in dialysis patients.

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.

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.

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.

Interferon monotherapy for dialysis patients with chronic hepatitis C: an analysis of the literature on efficacy and safety

OBJECTIVE

Hepatitis C virus (HCV) is prevalent in patients with end stage renal disease who are on dialysis. Liver disease from HCV is a cause of substantial morbidity and mortality after kidney transplantation in infected recipients. Effective treatment of chronic HCV is needed in this group of patients. We aimed to determine from the literature the efficacy and safety of interferon monotherapy in dialysis patients with chronic HCV.

METHODS

We reviewed the literature from 1986 to 2001 on the efficacy of interferon monotherapy in patients with HCV and end stage renal disease who were on dialysis. The outcomes measured were sustained viral response (SVR) and drop-out rate.

RESULTS

We reviewed 17 studies, of which 11 studies with a total of 213 patients met criteria for our analysis. Eight studies evaluated 3 million units (MU) three times/wk (t.i.w.), and three studies evaluated higher doses. The pooled SVR for 3 MU was 33% (95% CI = 21-51%). The pooled SVR for genotype 1 patients was 26% (95% CI = 15-37%). Of 152 patients in eight studies treated with 3 MU t.i.w. of interferon monotherapy, 45 patients (29.6%) discontinued therapy because of side effects.

CONCLUSIONS

Our analysis suggests that interferon monotherapy is more effective in patients on dialysis than in patients with normal renal function. Interferon monotherapy is associated with more adverse events in dialysis patients. The optimal dose and duration of interferon monotherapy and selection criteria of dialysis patients need to be studied further in clinical trials.

Thrombopoietin production in human hepatic cell cultures (HepG2) is resistant to IFN-alpha, IFN-beta, and IFN-gamma treatment

Thrombocytopenia is an important complication of interferon (IFN) therapy for chronic viral hepatitis. To study whether IFN interferes with hepatic thrombopoietin (TPO) synthesis, we used the human hepatoma cell line HepG2. Our results show that IFN-alpha, IFN-beta, or IFN-gamma did not impair TPO mRNA expression, as determined by quantitative RT-PCR, even when high IFN doses (up to 5000 U/ml) or long-term incubations (up to 14 days) were applied. Neither was the rate of secretion of immunoreactive TPO reduced on IFN treatment. These findings support the concept that IFNs primarily mediate effects on megakaryocytic cells and platelets rather than on TPO-producing hepatocytes.

Hepatitis C therapy with long term remission after renal transplantation

Hepatitis C virus infection (HCV) is common in patients with end-stage renal disease (ESRD) and long observation periods have shown the detrimental effect of HCV infection on patient and graft survival after renal transplantation. At present, interferon is the most important agent for the treatment of hepatitis C in ESRD; however, limited information exists concerning the long-term response of patients who undergo renal transplantation after successful antiviral therapy. We describe the evolution of HCV infection in a dialysis patient with hepatitis C who was successfully treated with interferon alpha and then underwent renal transplantation. He received aggressive immunosuppression during the induction phase and for allograft rejection; however, regular screening showed complete absence of biochemical and virological relapse of HCV over a 6-year post-transplantation period. We conclude that interferon can offer excellent response in selected dialysis patients with hepatitis C. Alternative strategies with newer antiviral agents are currently under active investigation.

Role of blood platelets in infection and inflammation

Blood platelets are here presented as active players in antimicrobial host defense and the induction of inflammation and tissue repair in addition to their participation in hemostasis. Megakaryopoiesis is inhibited after acute infection with viruses or bacteria. In contrast, chronic inflammation is often associated with reactive thrombocytosis. Platelets can bind and internalize pathogens and release microbicidal proteins that kill certain bacteria and fungi. By making cell-cell contacts with leukocytes and endothelial cells, platelets assist white blood cells in rolling, arrest and transmigration. On stimulation by bacteria or thrombin, platelets release the content of their alpha-granules, which include an arsenal of bioactive peptides, such as CC-chemokines and CXC-chemokines and growth factors for endothelial cells, smooth muscle cells and fibroblasts. Thus, integral to innate immunity, the tiny little platelets may become bombshells when irritated by pathogens.

Rapid suppression of hematopoiesis by standard or pegylated interferon-alpha

BACKGROUND & AIMS

Treatment of chronic hepatitis C with interferon (IFN)-alpha often has hematotoxic effects. We evaluated the effects of acute vs. chronic and standard vs. pegylated IFN-alpha on hematopoiesis.

METHODS

We studied hematopoiesis in 46 patients with chronic hepatitis C receiving single high-dose IN-Falpha2b followed by daily dose standard or weekly pegylated IFN before combination antiviral therapy.

RESULTS

Single high-dose therapy resulted in a significant drop in hemoglobin (HB), leukocytes, and platelet count. Although platelets, stimulated by a significant increase in thrombopoietin (TPO), and leukocytes recovered quickly, HB remained below baseline for 7 days. Daily standard or weekly pegylated IFN-alpha leads to a more pronounced drop in all 3 lineages with concomitant increases in TPO and erythropoietin (EPO). No difference was observed between standard and pegylated IFN, except for HB, which fell more during pegylated IFN therapy. Consecutive combination antiviral therapy aggravated the anemia but not the drop in leukocytes or thrombocytes.

CONCLUSIONS

The drop in all 3 hematopoietic lineages through IFN-alpha treatment, high-dose standard, standard daily dose, or pegylated, is caused by a combination of bone marrow inhibition and probably some other rapid acting mechanisms. Hematopoietic growth factors are increased as a consequence but cannot overcome the bone marrow suppression.

Detection and prevention of hepatitis C in dialysis patients and renal transplant recipients. A long-term follow up (1989-January 1997)

BACKGROUND

Hepatitis C is frequent problem in dialysis wards.

DESIGN

A long time (1989-97) follow up of hepatitis C virus (HCV) infection in a Swedish nephrology unit was performed with anti-HCV screening, confirmatory antibody tests, viral RNA detection and molecular characterization. Case histories were reviewed with focus, onset of infection, liver morbidity and mortality.

RESULTS

In October 1991, 10% (19 of 184) of the patients in the unit (haemodialysis-, peritoneal dialysis and transplanted patients) were verified or suspected HCV carriers, whilst the number at the end of 1996 was 8%, (13 of 157). Most patients were infected before 1991 but only in one case from a known HCV-infected blood donor. No new HCV infections associated with haemodialysis occurred during the study period. A total of 13 of 24 viremic patients had HCV genotype 2b, a pattern suggesting nosocomial transmission. This was further supported by phylogenetic analysis of HCV viral isolates in seven. HCV viremia was also common in patients with an incomplete anti-HCV antibody pattern as 8 of the 12 indeterminant sera were HCV-RNA positive.

CONCLUSIONS

Awareness, prevention, identification of infected patients and donor testing limited transmission. Indeterminant recombinant immunoblot assays (RIBA)-results should be regarded with caution as a result of the relative immunodeficiency in uremic patients. Our data indicate nosocomial transmission in several patients.

Spectrum of liver damage and correlation with clinical and laboratory parameters in HCV infected hemodialysis patients

There are conflicting results in studies concerning the best marker for liver histopathological features of HCV infection in HD patients. We planned a prospective study to follow HCV viremia and laboratory parameters of HD patients and correlate these with clinic features and histopathological findings. We included 68 HCV infected patients (45 male, 23 female, age: 39.8 +/- 11.9 years, HD duration: 58.2 +/- 36.4 months) in our study. The follow-up period after the biopsy was 33.2 +/- 20.3 months. Patients liver enzyme (alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyl transferase (GGT)) levels were determined monthly and ferritin levels every three months, and the mean value was recorded. We also screened patients for HCV RNA. During the follow-up period, 22 (32.4%) of the patients had positive RNA, 26 (38.2%) negative RNA. 20 (29.4%) had intermittent RNA positivity. The patients with high grade of portal necroinflammatory activity had significantly higher AST and ALT levels. In addition patients with high grade lobular activity had significantly shorter HD and HCV infection duration and higher AST, ALT and ferritin levels. AST levels were negatively correlated with duration of HD and HCV infection, and positively correlated with GGT and ferritin levels. Additionally, we found that ALT levels were negatively correlated with HD duration and positively correlated with GGT levels. ALT levels higher than 30 U/L were reflected necroinflammatory activity more significantly than levels higher than 40 U/L. Cirrhosis was detected in 5.9% of the patients, and we could not find any laboratory parameter that was correlated with stage of fibrosis. Although there is a high degree of liver involvement, cirrhosis is a relatively less frequent finding in HD patients. Serum aminotransferases and ferritin levels but not the pattern of HCV viremia are predictors of necroinflammatory activity in liver biopsy specimens. Liver biopsy obligatory to assess the disease activity in HD patients.

Influence of IFN-alpha on plasma erythropoietin levels in patients with hepatitis B virus-associated chronic active hepatitis

The influence of 3-month interferon-alpha (IFN-alpha) treatment on plasma erythropoietin (EPO) concentration in patients with chronic active hepatitis (CAH) induced by hepatitis B virus (HBV) infection was investigated. The study was carried out in 44 nonanemic patients divided into two groups: CAH B, 30 subjects not treated with IFN-alpha, and CAH B-IFN, 14 subjects treated with IFN-alpha for the first 3 months of the study (5 MU/m(2) body surface subcutaneously (s.c.) three times per week). In all patients, blood samples were taken at the beginning of the study (0) and after 1, 2, 3, 6, 9, and 12 months of observation. At the beginning, plasma EPO levels in the CAH B (27.8 +/- 2.21 mU/ml) and CAH B-IFN (27.3 +/- 3.04 mU/ml) groups did not differ significantly from each other and were significantly higher (p < 0.0001) than in healthy subjects (10.4 +/- 1.06 mU/ml). In patients in the CAH B group, plasma EPO concentrations did not change significantly during the whole observation period. In patients in the CAH B-IFN group, a transient, significant increase in plasma EPO level was found. The highest plasma EPO concentration in this group was noted after the third month of treatment (41.1 +/- 3.41 mU/ml). In conclusion, patients with CAH induced by HBV infection are characterized by increased plasma EPO concentrations, and IFN-alpha treatment in these patients causes a transient increase in the plasma EPO level.

The tolerance and efficacy of interferon-alpha in haemodialysis patients with HCV infection: a multicentre, prospective study

BACKGROUND

A prospective multicentre study was initiated in HCV-infected haemodialysis patients to assess the tolerance and efficacy of alpha-2b interferon.

METHODS

We had planned to include 120 patients with HCV RNA detectable by polymerase chain reaction (PCR) (Amplicor Roche) and histologically documented chronic hepatitis. The dose of alpha-interferon was 3 million units (MU) three times weekly (TTW), to be reduced to 1.5 MU TTW in case of side-effects. Tolerance was evaluated monthly; virological efficacy was evaluated by PCR. A liver biopsy was performed at month 18 (M18).

RESULTS

(a)

TOLERANCE

After 37 patients had been included, the study was discontinued by the promoting institution because of severe side-effects requiring that treatment be stopped in 19 patients. The side-effects were: cardiac (4) neuropsychiatric (2), digestive (3), acute necrosis of the graft (1), severe asthenia (9), minor side-effects were observed in 22 patients. A complete 12-month course was completed in 12 patients for the 3 MU TTW dose and in six patients for the 1.5 MU TTW reduced dose. Normal ALT level (OR, 0.16; CI 95%, 0.03-0.89) at inclusion was associated with interruption of treatment (univariate analysis). (b)

EFFICACY

Sustained virological response was observed in only seven (18.9%), of the 18 patients who completed the treatment (38%). Increased ALT at inclusion (OR, 1.04; CI 95%, 1.01-1.09) and cumulated doses of interferon (OR, 1.01; CI 95%, 1.004-1.026) were jointly associated with a sustained response, while positive PCR at M2 was strongly predictive of treatment failure.

CONCLUSION

Tolerance of interferon is poor in haemodialysis patients. Sustained response is fairly high in patients who have 12 months of treatment and seems to be based on the immune status of the patients (ALT) and the cumulative doses of interferon.