Interferon treatment for chronic hepatitis C in haemodialysis patients: suggestions based on a small series

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.

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.

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.

Clinical usefulness of a new hepatitis C virus RNA extraction method using specific capture probe and magnetic particle in hemodialysis patients

Hemodialysis patients are a high-risk group for hepatitis C virus (HCV) infection. Assessment of HCV infection using HCV-RNA assay among dialysis patients is important for the issue of safety and environmental protection. However, polymerase chain reaction (PCR)-based methods are unsuitable for analyzing samples from dialysis patients because the conventional centrifugal extraction method fails to eliminate heparin, a potent inhibitor of PCR. In this study, we evaluated the usefulness of a HCV-RNA extraction method using probes and magnetic particles for hemodialysis patients in comparison with the centrifugal method. The study population consisted of 17 HCV antibody-positive patients undergoing hemodialysis. These 17 patients consisted of 12 HCV carrier patients and five patients with past HCV infection. One hundred and two samples from these patients were measured using the centrifugal and magnetic methods. Moreover, we prepared five standards that included theoretically 5 KIU/mL of HCV. One was made from non-HD patient's serum and the other four were from hemodialysis patients' serum. These standards were measured using the two methods. False-negative results were not observed with the magnetic method, but were observed in five out of 102 samples with the centrifugal method. Studies using standard samples revealed that accurate HCV-RNA measurement is achieved using the magnetic method. In conclusion, the present study showed that this magnetic extraction method is a highly reproducible and reliable assay to obtain correct information about the presence of the infective virus itself in the hemodialysis setting. Precise identification of HCV-RNA using this specific method is considered to be useful in preventing HCV infection in hemodialysis units.

Natural history of chronic hepatitis C in patients on hemodialysis: Case control study with 4-23 years of follow-up

AIM: Hepatitis C virus (HCV) infection is very common among end-stage kidney disease patients on hemodialysis, but its natural history is not known.

METHODS: In this study, 189 dialysis patients (case) positive for HCV antibodies who were followed up for more than 4 years were compared with twice as many sex/age matched controls with chronic hepatitis C who were diagnosed in the same month as the case and followed up for comparable periods. The longest follow-up was 23 years in dialysis cases. The disease activities were graded into “asymptomatic” if ALT was less than 40 (35 in cases) IU/L, “low activities” if ALT was 40 (35)-79 IU/L, and “high activities” if ALT was above 80 IU/L during the last or latest 4 year period.

RESULTS: All 25 dialysis cases who were followed up for more than 15 years were asymptomatic and 15 of them were negative for HCV RNA. Of the 50 controls followed up for more than 15 years, 34 had high activities, and none cleared HCV RNA. There were 60 controls who were asymptomatic, but they were all positive for HCV RNA, while 22.3% of asymptomatic dialysis cases were RNA negative. No dialysis patients with chronic hepatitis C progressed to cirrhosis, whereas the disease progressed to cirrhosis in more than one quarter of the controls. These differences were highly significant (P < 0.0001).

CONCLUSION: Chronic hepatitic C among hemodialysis patients is mild in disease activity, and is not progressive, perhaps due to immunological abnormalities in these patients. Hepatic C virus is frequently cleared in asymptomatic dialysis patients during a long course. A possible mechanism for viral clearance is viral particle destruction on the surface of the dialyzer membrane.

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.

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.

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.

Hepatitis B and C and renal failure

Hepatitis C is the most common cause of liver disease in the dialysis patient. The prevalence of chronic hepatitis C determined by anti-HCV testing in this population ranges from 6% to 38%. Using second generation EIA assays, the prevalence of anti-HCV among patients participating in the 1997 National Surveillance of Dialysis Associated Diseases in the United States was 9.3%. Polymerase chain reaction testing for HCV RNA has shown that the prevalence of HCV infection can be as high as 20% to 30% of dialysis patients. The causes and source of infection in patients with chronic renal failure on hemodialysis are multiple. Before the introduction of routine screening of blood donors for anti-HCV, blood transfusions were an important risk factor for acquisition of hepatitis C. Other potential sources of infection include exposure to contaminated equipment and nosocomial routes such as patient-to-patient exposure. The risk of infection appears to correlate with the duration of hemodialysis and the number of transfusions. Interestingly, dialysate and buffers have been shown to be virus free even when used in hepatitis C infected patients. The natural history of chronic hepatitis C infection in patients with renal failure is not well characterized. Although persistent elevations in ALT levels occur in 12% to 50% of dialysis patients, the frequency of persistently normal ALT levels in HCV-infected dialysis patients appears to be higher than in HCV-infected patients without renal failure. Overt liver disease and liver failure rarely occur. The degree of inflammation in liver biopsies of renal failure patients is usually mild. Thus, progressive liver disease may be less common in patients with advanced renal disease but further studies are required to assess the true impact of hepatitis C infection in this high risk population. The impact of hepatitis C infection on morbidity and mortality of patients with end-stage renal disease remains poorly defined. Initial studies have failed to show a significant increase in mortality among HCV-infected hemodialysis or renal transplant patients within the first 5 years following transplantation. In contrast, recent studies with extended follow-up of renal transplant recipients suggest that hepatitis C infection may affect patient and graft survival during the second decade. Further studies are required to identify the mechanisms of infection of patients with end-stage renal disease and to define better treatment strategies for these patients before and after kidney transplantation.

Efficacy of interferon for chronic hepatitis C virus-related hepatitis in kidney transplant candidates on hemodialysis: results after transplantation

OBJECTIVES

Interferon-alpha (IFN) may have undesirable effects on a functioning graft. The aim of this study was to evaluate IFN treatment in kidney transplant candidates during the hemodialysis period as well as the results after transplantation.

METHODS

A total of 29 noncirrhotic hemodialysis patients with chronic hepatitis C virus (HCV) infection (based on long-term rise in ALT, HCV serology, HCV RNA by polymerase chain reaction methods, and histological evidence) were included. Tolerability to IFN treatment, pre- and posttransplantation therapeutic results, and long-term outcome were recorded. IFN regimen consisted of 3 million units (MU) times per week after hemodialysis sessions for 6 months, followed by 1.5 MU after each hemodialysis session for an additional 6 months. All patients gave informed consent for participation.

RESULTS

IFN therapy was fairly well tolerated. Adverse effects due to IFN toxicity, renal disease, or causes related to the immunological properties of IFN were observed in 24% of patients. At the end of treatment, ALT had normalized in 23/28 patients (82.1%), and HCV RNA had cleared in 23/28 patients (82.1%). During follow-up, HCV RNA was persistently negative in 18 patients (64%, including transplant recipients). A total of 14 patients (nine HCV RNA-negative) received a kidney transplant. Mean follow-up after the procedure was 41 +/- 28 months. In all, 12 patients had a functioning graft, one had acute vascular rejection, and one died of carcinoma. All transplanted patients maintained normal ALT levels, and eight remained HCV RNA-negative.

CONCLUSIONS

Treatment results in our study population were better than those observed in the general population. The long-term response achieved, which was maintained after transplantation, supports the use of IFN for HCV hepatitis in kidney transplant candidates under hemodialysis.

Prognosis of anti-hepatitis C virus antibody-positive patients on regular hemodialysis therapy

The prevalence of hepatitis C virus (HCV) infection is high in patients who are on chronic hemodialysis, but the role of HCV infection and HCV-related liver disease in the mortality of these patients has not been shown. Therefore, we conducted a prospective cohort study of 1470 patients who were on chronic hemodialysis (17 to 89 yr old) from 16 dialysis centers in Japan. Among them, 276 patients (18.8%) were positive for anti-HCV antibodies and 1194 patients were negative. The patients were followed for 6 yr from 1993 to 1999. Only one case, a patient from the anti-HCV-antibody-positive group, was lost to the follow-up during this period. The mortality was higher in the anti-HCV-antibody-positive group (91 of 276 patients died) than in the anti-HCV-antibody-negative group (277 of 1193 died) (33.0% versus 23.2%, P< 0.01). A Cox proportional hazard examination showed that positivity for anti-HCV antibodies was one of the risk factors for death with an adjusted relative risk of 1.57 (95% confidence interval, 1.23 to 2.00). As a cause of death, hepatocellular carcinoma and liver cirrhosis were significantly more frequent in the anti-HCV-antibody-positive patients than in the anti-HCV-antibody-negative patients (5.5% versus 0.0%, P< 0.001; 8.8% versus 0.4%, P< 0.001, respectively). These findings show that the mortality is increased in anti-HCV-antibody-positive patients who are on chronic hemodialysis. Hepatocellular carcinoma and liver cirrhosis are factors that may influence the mortality.

Pharmacokinetics of natural human IFN-alpha in hemodialysis patients

A pharmacokinetic study of natural human interferon-alpha (IFN-alpha) was conducted in hemodialysis patients. Natural human IFN-alpha was intramuscularly (i.m.) administered to 8 hemodialysis patients at a single dose of 5 million IU and to 7 patients undergoing hemodialysis at the same dose once daily for 5 successive days. The serum antiviral activity was determined by a cytopathic effect bioassay. In the single dose study, the serum antiviral activity reached a maximum (Cmax) of 56.4 +/- 33.3 IU/ml at 8.3 +/- 2.7 h after dosing, and the area under the serum concentration-time curve (AUC0-24h) was 957.2 +/- 601.8 IU h/ml. The Cmax and AUC0-24h values at day 5 following the repeated dosing were both 2.6-fold higher than those of day 1, and the serum antiviral activity reached a steady state within 3 days after initiation of repeated administration. The serum antiviral activity in hemodialysis patients showed a tendency to increase compared with that in the subjects with normal renal function, but the magnitude of the differences was not great. In one nonhemodialysis patient with poor renal function (creatinine clearance < 30 ml/min), no increases in serum antiviral activity owing to repeated dosing were observed. The main adverse events seen were fever (4 of 13, 30.8%), leukopenia (3 of 13, 23.1%), and fatigue (2 of 13, 15.4%). These results suggest that dosage modifications of natural human IFN-alpha are unnecessary for patients with low renal function, even those undergoing hemodialysis.

Interferon-alpha in chronic hepatitis C infection in dialysis patients

This study assesses the efficacy and adverse effects of interferon-alpha (IFN-alpha) administered at a dosage of 3 million units three times weekly for 1 year in 17 hemodialysis patients with hepatitic C virus (HCV)-associated chronic hepatitis (biopsy proven). The patients were prospectively followed up for a period of 18 months. Liver biopsy was repeated after 6 months of treatment in 13 patients. Patients were classified according to the histological activity index. Biochemical and virological responses were evaluated at the end (end-of-treatment response) and 6 months after completion of therapy (sustained response). HCV RNA became negative in 76% of the patients after 12 weeks of treatment, in 88% after 12 months of treatment, and in 71% of the patients 6 months after completion of therapy. HCV genotype 4 was found in 60% of our population. Alanine aminotransferase (ALT) levels were initially increased in only 6 patients and normalized in 4 of these patients after 12 weeks of therapy, with end-of-treatment and sustained biochemical responses of 83% and 67%, respectively. Of 13 patients who underwent liver biopsies after 6 months of therapy, 11 patients (85%) showed histological improvement. One patient could not tolerate therapy because of marked lethargy and myalgia; the other patients had minor side effects that did not require discontinuation of treatment. Two patients received a cadaveric renal transplant after 1 year of IFN treatment, and they continued to maintain biochemical and virological responses after a follow-up of 17 and 28 months, respectively.

Consumption of alcohol in the presence of hepatitis C virus is an additive risk for liver damage

BACKGROUND

Whether alcohol consumption influences the development of hepatitis C in the presence of a latent infection needs to be determined.

METHODS

The interaction between alcohol intake and hepatitis C virus infection with regard to development of liver injury was cross-sectionally investigated for 399 inhabitants of a town in Nagano Prefecture, Japan. In this town, the prevalence of hepatitis C virus infection is 32.4%.

RESULTS

The levels of indicators of liver function were significantly higher among subjects of both sexes who carried the antibody to hepatitis C virus than among those without the antibody. Among men, higher levels of liver function were more frequent among alcohol drinkers than among nondrinkers, suggesting that alcohol consumption may aid in the development of liver injury, even among subjects with a latent hepatitis C virus infection. gamma-Glutamyl transpeptidase activity was more sharply increased in relation to alcohol intake among subjects with hepatitis C virus infection than among those without it, suggesting that the presence of infection will influence alcohol-induced liver damage.

CONCLUSION

Alcohol consumption and a concomitant hepatitis C virus infection apparently facilitate the development of hepatitis.

Acute hepatitis C among renal failure patients on chronic haemodialysis

Hepatitis C virus (HCV) infection is common in haemodialysis units, yet little information is available about the clinical feature of acute hepatitis C among renal failure patients. The present study is based on 49 cases of acute hepatitis C seen at a haemodialysis centre where sporadic nosocomial infection was occurring up to June 1993. Liver function tests were done at 4 weekly intervals on all dialysis patients, anti-HCV antibodies were tested by the C-100 and second generation tests and serum HCV-RNA was determined by the branched DNA and Amplicore tests. Diagnosis of acute hepatitis C was made on the basis of an acute rise in alanine aminotransferase (ALT) and seroconversion to positive anti-HCV antibodies. Clinical presentation of acute hepatitis was generally mild with rare overt jaundice and the diagnosis was possible only from increased ALT, which was generally low. Spontaneous resolution of acute hepatitis within 8 months with clearance of viral RNA occurred in only four cases, 91.8% of patients developing chronic hepatitis. Biopsy in 12 cases with high ALT levels showed mild to moderate inflammatory activities. In conclusion, the clinical presentation of acute hepatitis C is generally mild in chronic haemodialysis patients, but spontaneous resolution is infrequent. A longer follow-up period is required for defining the long-term prognosis.

Hepatitis in patients with end-stage renal disease

Hepatitis B and hepatitis C are two common pathogens causing chronic hepatitis in patients with end-stage renal disease (ESRD). With the acceptance of hepatitis B s antigen (HBsAg) screening, infected patients have been identified and isolated over the past 20 years. Consequently, hepatitis B is now being seen less frequently in dialysis units. Even though hepatitis B has become less of a problem, non-A, non-B hepatitis has been recognized as a significant problem since 1979. With the availability of serological testing for hepatitis C virus (HCV), more specific information is now available in regard to HCV infection in dialysis patients. The prevalence of anti-HCV in haemodialysis (HD) patients is quite variable, ranging from 5 to over 50%. Anti-HCV positivity is associated with previous blood transfusions, mode of therapy and duration of haemodialysis. In Spain and Italy, the annual seroconversion rates of HCV antibodies in dialysis patients are 2-9%; this rate was much higher in Taiwan (15%). Whether patients with HCV infection should be identified and isolated during HD treatment is an issue of controversy. Transplantation is associated with increases in hepatitis B virus (HBV) replicative markers. The survival disadvantage in HBsAg-positive recipients usually did not become apparent until 8 years after transplantation. Hepatitis C virus-infected renal transplant recipients are presumably in a similar situation to patients with hepatitis B, although confirmatory data are currently lacking. Coinfection of HBV and HCV may lead to aggressive liver disease and cirrhosis. A hepatitis B vaccine is recommended for all susceptible dialysis patients. Dialysis patients have lower response rates to hepatitis B vaccines than do other people. Currently, no vaccine is available for hepatitis C. To date, there are no effective treatments available for hepatitis B and hepatitis C. Combination therapy with interferon/lamivudine for hepatitis B and interferon/ribavirin for hepatitis C may offer a promise of effective control of viral replication in the future.

Hypoaminotransferasemia in patients undergoing long-term hemodialysis: clinical and biochemical appraisal

BACKGROUND & AIMS

It has been reported that patients with chronic renal failure have low serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels as a result of vitamin B6 deficiency. Chronic hepatitis C is common among patients undergoing hemodialysis, and low aminotransferase levels cause diagnostic problems. The aim of this study was to determine the cause of hypoaminotransferasemia.

METHODS

Serum levels of vitamin B6 and its coenzyme were reassessed in relation to AST and ALT levels in patients undergoing long-term hemodialysis using high-performance liquid chromatography.

RESULTS

The mean (+/- SD) serum AST and ALT levels in 304 patients negative for hepatitis B surface antigen and anti-hepatitis C virus were 9.2 +/- 2.4 and 7.4 +/- 1.7 IU/L, respectively. In 556 normal adults, they were 22.7 +/- 5.4 and 18.0 +/- 4.0 IU/L, respectively (P < 0.001). Mean serum vitamin B6 and pyridoxal-5'-phosphate levels in patients undergoing dialysis were not reduced compared with the control, although occasionally patients had low levels. The AST and ALT assay reagents in Japan do not contain added pyridoxal-5'-phosphate; addition of pyridoxal-5'-phosphate (0.1 mmol/L) to the reagent significantly increased measurements to similar extents in both groups.

CONCLUSIONS

Serum AST and ALT levels in patients undergoing dialysis are very low, but they are not a result of vitamin B6 deficiency. The upper normal limits of AST and ALT levels in patients undergoing dialysis should be reduced considerably, and these levels should be interpreted with caution in the diagnosis of liver disease.