Hepatitis C in dialysis patients: relationship to blood transfusions, dialysis and liver disease

Hepatitis C Antibodies in Patients on Peritoneal Dialysis: Prevalence and Risk Factors

Our objective was to determine the prevalence of the antibody to hepatitis C (anti-HCV) in a population of endstage renal failure patients on continuous peritoneal dialysis (CPD) and study the possible risk factors associated with anti-HCV seropositivity and seroconversion. A cross-sectional study included 155 adult patients enrolled in the CPD program in a single renal unit of a teaching hospital who were screened for anti-HCV by second-generation enzyme immunoassay, which was confirmed by recombinant immunoblot assay. Serum was also assayed for hepatitis B surface antigen (HBsAg). History of renal transplantation, blood transfusions, and exposure to hemodialysis was obtained from medical records.

Ten of 155 patients (6.5%) in this study population were anti-HCV positive [anti-HCV(+)] and 11/155 (7.1%) were HBsAg positive; no patient was positive for both. All the anti-HCV(+) patients were on continuous ambulatory peritoneal dialysis (CAPD); no continuous cycling peritoneal dialysis (CCPD) patient was anti-HCV(+). Exposure to hemodialysis was a risk factor for anti-HCV seropositivity, with 7 out of 10 (70%) anti-HCV(+) patients having been on hemodialysis compared to 55/134 (41%) anti-HCV(-) (p < 0.05, Fisher's exact test). No difference was noted between anti-HCV(+) and anti-HCV(-) groups in relation to age, gender, duration on CPD, renal transplantation, or exposure to blood transfusions. Seroconversion occurred in only one patient after a mean observation period of 20±0.6 months.

The prevalence of anti-HCV seropositivity in this population of CPD patients is 6.5%, and HBsAg is 7.1%. Exposure to hemodialysis is a significant risk factor for development of anti-HCV seropositivity. Seroconversion rate appears to be low.

Hepatitis C Infection Become a Common Issue Among Hemodialysis Patients in a Hemodialysis Center Jakarta, Indonesia, and Survival Comparison of Hemodialysis Patients with Hepatitis Infection between Two Hemodialysis Centers in Jakarta, Indonesia, and Penang, Malaysia

Background:

According to the Association of Nephrologist in Indonesia (Pernefri) recommendation, isolation and using special hemodialysis machines are not necessary for hemodialysis (HD) patients who have been infected by hepatitis C virus (HCV), while according to the Ministry of Health Malaysia recommendation, hepatitis C patients should be dialyzed in a separate room or a separate area with a fixed partition and dedicated machines.

Aim:

The aim of this study was to identify the correlation between the recommendation which had been followed by two HD centers in different countries and the impact of that on the hepatitis C infection issue.

Methods:

A cohort prospective and retrospective study was done in this research. The study included HD patients who were followed up for 9 months and who died in the last 5 years. Universal sampling was used to select the patients based on inclusion criteria.

Results:

There was a significant relationship between HCV during the first checkup and HCV during the second checkup during the 9-month follow-up of HD patients in a HD center, Jakarta, Indonesia. The total number of patients who had hepatitis C during the first and second checkups was also different in this HD center.

Conclusion:

Besides providing special HD rooms and machines for HD patients with hepatitis C, minimizing blood transfusion to the patients on HD is also important to reduce the chance for the patients to acquire hepatitis C and to increase the percentage of survival.

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.

Risk factors of HCV seroconversion in hemodialysis patients in tabriz, iran

BACKGROUND

Hepatitis C virus (HCV) infection is a significant health concern in patients with end-stage renal disease under dialysis. Epidemiological studies have reported a prevalence rate of 5.5-55.9% for this condition in Iran.

OBJECTIVES

We evaluated the risk factors for HCV infection and seroconversion in hemodialysis patients.

PATIENTS AND METHODS

A retrospective analysis was performed on 455 hemodialysis patients from each of the five dialysis units in Tabriz, northwest Iran. Possible risk factors for HCV infection and seroconversion were evaluated.

RESULTS

A total of 37 patients were HCV positive (8.1% of the study population) and seroconversion occurred in 18 of them during the dialysis treatment (3.95% of the study population). History of renal transplantation (44.4%, P < 0.0001), surgical intervention (except for renal transplantation and AV fistula placement) (94.4%, P = 0.03), and mean duration of dialysis (106.06 ± 55.519, P < 0.0001) had strong statistically significant associations with the seroconversion.

CONCLUSIONS

The current study indicates increased risk for HCV infection in patients under dialysis and its relation with the mean duration of hemodialysis, history of renal transplantation and surgical intervention. Considering the immune deficiency in these patients, intense education to both patients and medical staff will be beneficial.

Hepatitis B and C infection in haemodialysis patients in Libya: prevalence, incidence and risk factors

BACKGROUND

Patients receiving maintenance haemodialysis (HD) are at higher risk for acquiring Hepatitis B Virus (HBV) and Hepatitis C Virus (HCV) infections than the general population. Strict infection control measures are essential to prevent nosocomial transmission. We aimed to investigate the incidence and prevalence of HBV and HCV infection in the HD population of Libya as well as risk factors for infection.

METHODS

All adult patients receiving maintenance HD (n=2382) in Libyan dialysis centres (n=39) were studied between May 2009 and October 2010. Testing for Hepatitis B surface antigen (HBsAg) and anti-HCV antibodies was performed at initiation of dialysis and every 3-6 months thereafter. Patients who were sero-negative for HBV and HCV (n=1160) were followed up for 1 year to detect sero-conversions.

RESULTS

Participant median age was 49 years and 58% were male. 831 patients (34.9%) were sero-positive for HBV and/or HCV (anti-HCV positive 31.1%; HBsAg positive 2.6%; both positive 1.2%). Of the sero-positive patients 4.7% were known to be infected before the initiation of HD. The prevalence of HBV±HCV infection varied widely between HD centres from 0% to 75.9%. Sero-positive patients were younger, had longer time on dialysis and more previous blood transfusions. Prospective follow-up revealed an incidence of sero-conversion of 7.7% during 1 year (7.1% HCV; 0.6% HBV). Wide variation in rates of newly acquired infections was observed between dialysis centres. All new HBV cases were referred from centres already treating HBV infected patients. New HCV infections were reported in most centres but the rate of HCV sero-conversion varied widely from 1.5% to 31%. Duration of dialysis, history of previous renal transplant and history of receiving HD in another centre in Libya were significantly associated with sero-conversion.

CONCLUSION

Patients on maintenance HD in Libya have a high incidence and prevalence of HCV infection and lower rates of HBV infection. The factors associated with HBV and HCV infection are highly suggestive of nosocomial transmission within HD units. Urgent action is required to improve infection control measures in HD centres and to reduce dependence on blood transfusions for the treatment of anaemia.

The role the type of vascular access plays in the transmission of hepatitis C virus in a high prevalence hemodialysis unit

BACKGROUND

The necessity of having a vascular access site as well as extracorporeal blood circulation, may add to the risk for patients being dialyzed in units with high HCV prevalence of acquiring hepatitis C virus (HCV) infection. This study endeavors to determine the role the type of vascular access plays in the transmission of HCV infection in the hemodialysis (HD) unit of a Middle Eastern country.

METHODS

The records of 198 patients with end-stage renal disease (ESRD) enrolled on maintenance HD from November 1995 to November 2000 at this tertiary care center, were retrospectively reviewed to match the HCV prevalence and seroconversion rates among patients groups being dialyzed through various types of vascular accesses. Factors such as, number of units of blood transfused and dialytic age (time-span since the initiation of the HD treatment), implicated in transmission of HCV infection in HD units, were also recorded, and compared among these cohorts.

RESULTS

The overall, high HCV seroprevalence of 43.4% (86/198) and annual seroconversion rate of 8.6% per year were recorded. Patients with arteriovenous fistula (AVF) documented peak anti-HCV prevalence [61.7% (63/102)] and annual seroconversion rates (12.3%) as compared to lowest prevalence of 12.9% (4/34) and seroconversion rate of 2.5%, observed among patients with permanent Catheters (PC). Patients dialyzed through polytetrafluoroethylene (PTFE) grafts recorded the next highest HCV prevalence of 47.8% (11/23) with seroconversion rate of 9.5% but temporary catheter (TC) group had HCV prevalence of 19% (8/42) and seroconversion rate of 3.8% [Odd Ratio (OR)-1.58, 95% Confidence Interval (CI) (0.37-7.12), p-NS].

CONCLUSIONS

Considerably higher annual seroconversion rates in AVF [OR-10.90, 95% CI (3.2-40.0), p<0.0001] and PTFE [OR-5.71, 95% CI (1.31-26.79), p<0.016)] groups, appear to suggest that the patients being dialyzed through AVF and PTFE, carried significantly higher risk of acquisition of HCV infection compared to those dialyzed through TC and PC (reference group). This could possibly be attributed to likely accessibility of HCV to blood circulation due to possible breakdown of standard infection control precautions during repeated punctures and cannulations of AVF and PTFE to perform a HD, in a unit with high baseline HCV prevalence.

Prevalence of hepatitis C virus infection and related risk factors among Iranian haemodialysis patients

Hepatitis C virus (HCV) infection is common among patients undergoing haemodialysis, and liver disease is an important cause of morbidity and mortality in this population. Management of HCV-related liver disease is a major health concern in patients with end-stage renal disease (ESRD) undergoing haemodialysis. To investigate the prevalence of HCV infection in patients on haemodialysis and its associated risk factors, we conducted a prospective case series study of 838 patients on haemodialysis in Tehran, Iran. Patients were selected randomly (cluster sampling) and all were screened for anti-HCV antibodies, using ELISA 3rd generation and confirmed by using RIBA 2nd generation. We found that 111 patients (13.2%) were infected. By applying univariate analysis, longer duration on haemodialysis (P = 0.000), more weekly dialysis sessions (P = 0.03), history of blood transfusion (P = 0.03) and history of previous renal transplantation (P = 0.01) were found to be associated with a higher rate of HCV infection. Multivariate analysis revealed that only length of time on dialysis (P = 0.000) and history of blood transfusion (P = 0.02) were significantly associated with HCV infection. The more the units transfused, the higher the rate of HCV infection. Our results suggest that early transplantation and avoidance of blood transfusion, as much as possible, are the two most important practical interventions to reduce the HCV exposure rate in our patients on haemodialysis.

Kidney graft survival in patients with hepatitis C: a single center experience

Hepatitis C virus (HCV) infection is highly prevalent in renal transplant candidates; however, its effect on the transplant outcome is still controversial. The aim of the present study was to determine the effect of HCV infection in the outcome of kidney transplantation in a single transplant center. The study population 144 HCV- randomized selected patients and 64 HCV+ patients transplanted from 1973 to 2000, followed for up to 60 months post-transplantation. This retrospective study included the following variables: type of dialysis, time on renal replacement therapy, number of transfusions before and after transplantation, number of transplants, type of donor, immunosuppression, and rejection episodes. The Kaplan-Meier method was used to estimate graft and patient survival. Log-rank test was used to assess the difference in survival between HCV+ and HCV-. A multivariate Cox proportional hazards model was used to analyze the relation between graft and patient survival. HCV+ and HCV- patients had similar demographic and clinical characteristics; however, a higher number of HCV+ patients received blood transfusions after transplantation. Patient survival was not significantly different in 39 HCV+ and 96 HCV- patients transplanted with living-related donors (71% and 77% at five yr, respectively). Similarly, there was not significant difference in 25 HCV+ and 48 HCV- patients transplanted with kidneys from deceased donors, although there was a tendency to better outcome in HCV- patients (55% and 72% at five yr respectively). Regarding graft survival, there was also no differences in HCV+ and HCV- recipients of living-related grafts (61% and 66% at five yr post-transplant, respectively) and recipients of kidneys from deceased donors (44% and 41%, respectively). The results show that HCV+ patients can be transplanted with the same success than HCV- patients.

Gamma glutamyltranspeptidase activity and viral hepatitis in dialysis population

BACKGROUND

Numerous investigations have reported that viral hepatitis is associated with significant hepatocellular damage, as expressed by raised aminotransferases in serum, in dialysis population. However, scarce information exists on the activity of gamma glutamyltranspeptidase (GGTP) in dialysis patients with infection by hepatotropic viruses.

OBJECTIVES

We measured serum GGTP values in a large cohort (n=757) of patients receiving long-term dialysis; healthy controls were also included. The relationship between GGTP values and a series of demographic, clinical, and biochemical parameters was analyzed.

METHODS

Serum GGTP levels were tested by spectrophotometry. A subset (n=333) of dialysis patients was tested by molecular technology (branched-chain DNA (bDNA) assay) to evaluate the relationship between serum GGTP and HCV viremia. A subgroup (n=78) of dialysis patients was analyzed by an ultrasound scan of gallbladder and biliary tract to assess the presence of gallstone disease. Multivariate analyses were made using regression models; serum GGTP values were included as a dependent variable. The usefulness of serum GGTP levels in detecting HBsAg and anti-HCV positivity was evaluated using receiver operating characteristics (ROC) curve analysis.

RESULTS

Univariate analysis showed that serum GGTP levels were significantly higher in HBsAg positive and/or anti-HCV positive patients than in HBsAg negative/anti-HCV negative patients on dialysis; 85.1+/-184.1 versus 25.86+/-23.9 IU/l (P=0.0001). The frequency of raised GGTP levels was 22.2% (41/184) among dialysis patients with chronic viral hepatitis. Multivariate analysis showed a significant and independent association between serum GGTP values and positive HBsAg (P=0.005) and anti-HCV antibody (P=0.0001) status. Mean GGTP values were significantly higher in study patients than controls, 32.32+/-60.02 versus 23.5+/-16.92 IU/L (P=0.01); however, no significant difference with regard to GGTP between study and healthy cohorts persisted after correction for age, gender, race, and viral markers. No relationship between gallstone disease and serum GGTP was found (NS). An independent and significant association (P=0.0291) between raised GGTP levels and detectable HCV RNA in serum was noted among patients tested by biology molecular techniques. ROC technology demonstrated that GGTP was equally useful for detecting HBV (P=0.0004) and HCV (P=0.0005) among dialysis patients.

CONCLUSIONS

We found an independent and significant association between serum GGTP values and HBsAg and/or anti-HCV antibody in dialysis population. Twenty-two percent of dialysis patients with chronic viral hepatitis had elevated GGTP. No difference in GGTP between HBsAg- negative/anti-HCV- negative dialysis patients and healthy individuals was found. Routine testing for serum GGTP levels to assess liver disease induced by hepatotropic viruses or other agents in dialysis population is suggested.

Hepatitis C in transplant recipients of solid organs, other than liver

Hepatitis C virus (HCV) infection is prevalent in candidates for, and recipients of, solid organ transplants. HCV infection can lead to diminished patient and allograft survival in the long-term in recipients of kidney transplants. Outcomes in recipients of other solid organ transplants (lung, heart, small bowel, pancreas, pancreas-kidney) are not well established. Large, well-designed, prospective studies are needed to answer these questions. Interferon therapy for HCV before transplantation can lead to improved outcomes. Therefore, transplant candidates should be considered for and offered interferon therapy before embarking on organ transplantation. Posttransplant interferon therapy can be complicated by acute allograft rejection and is not recommended, except with advanced liver disease.

Determination of the cut-off value of serum alanine aminotransferase in patients undergoing hemodialysis, to identify biochemical activity in patients with hepatitis C viremia

BACKGROUND

Elevated liver enzymes are infrequent in patients with hepatitis C virus (HCV) infection undergoing chronic hemodialysis (HD), suggesting that the alanine aminotransferase (ALT) is a poor predictor of hepatocellular damage in this population.

OBJECTIVE

To establish a more appropriate cut-off value of ALT to identify biochemical activity due to HCV infection in HD patients.

STUDY DESIGN

A total of 217 patients, with an average age of 51.2 years, were evaluated between January and October 2002; 130 were males (60%). Serum ALT was measured by a kinetic method in five consecutive monthly blood samples, from which an average was obtained and divided by the upper limit of normal (ULN). HCV antibodies were determined using an enzyme immunoassay, the serum HCV-RNA by nested-PCR and HCV genotype by hybridization of the amplified sequence from the 5'-non-coding region. The cut-off value of ALT was obtained from a ROC curve.

RESULTS

Within the 217 patients, 18 (8.3%) were anti-HCV-positive, 17 (7.8%) of whom were also HCV-RNA-positive. Genotype distribution was: 1a=47%; 1b=18%; 3a=35%. Mean ALT/ULN (0.77+/-0.57) of the 18 anti-HCV-positive cases was higher (p<0.001) than the negative group (0.38+/-0.23). The mean ALT/ULN (0.81+/-0.57) of the 17 HCV-RNA-positive cases was also higher (p<0.0001) than the negative cases (0.37+/-0.23). The cut-off value of ALT to distinguish the anti-HCV-positive from negative patients was 0.50% or 50% of the ULN (sensitivity=67%; specificity=83%). According to the HCV-RNA, the cut-off value of ALT was 0.45% or 45% of the ULN (sensitivity=71%; specificity=80%).

CONCLUSION

Reducing the cut-off of ALT by half, enables a better identification of biochemical activity in patients with HCV infection on chronic HD.

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.

[High prevalence and incidence of hepatitis C virus infections among dialysis patients in the East-Centre of Tunisia]

Hemodialysed patients are recognised as a group at increased risk of infection with hepatitis C virus (HCV). The aim of this study was to determine the prevalence and incidence of HCV infection among dialysis patients of the east-centre part of Tunisia. Two hundred and seventy-six patients dialysed until 2001 were recruited within seven hemodialysis units located in the cities of Sousse, Monastir and Mahdia. The serum markers of HCV infection were tested over the period of March 2000-December 2002, by a 3rd generation ELISA test for antibodies and by qualitative RT-PCR technique for viral RNA. The prevalence of anti-HCV antibodies and of HCV RNA was 32.6% (90 patients) and 25.7% (71 patients), respectively. Between 1998 and 2002, 20 new infections were documented in five of the seven dialysis units corresponding to an incidence of 2.34% per year, with an average time of contamination after the beginning of dialysis of 4.6 years. If all the infections are assessed to have occurred during dialysis, the density of incidence of HCV contamination was 4.4% per year of dialysis. A high correlation was noticed between the presence of HCV markers in serum and the duration of dialysis (F = 34.15, P < 0.0001). In the absence of other risk factors (transfusion, drug-addiction), these results plead for the nosocomial transmission of the observed HCV infections. A phylogenetic analysis of the E2 hypervariable region of the viral genome is in progress to confirm this assumption.

Influence of hepatitis B virus virema upon serum aminotransferase activity in dialysis population

BACKGROUND

The control of the spread of hepatitis B virus (HBV) infection within dialysis units has been one of the major advances in the management of patients with end-stage renal disease (ESRD). However, clinical and biochemical expression of HBV in dialysis patients have not been adequately addressed. Elevated values of serum aminotransferase activity are a sensitive measure of hepatocellular injury, but the role of HBV infection in the development of liver disease among dialysis patients has not been adequately analysed. Also, the clinical impact related to the virological characteristics of HBV in dialysis has not been evaluated.

METHODS

Demographic, biochemical and virological data from 727 patients undergoing chronic dialysis in seven dialysis units in northern Italy were collected in order to assess the biochemical consequences related to the presence of HBV infection in this population. We have measured by RT-PCR technology the titers of HBV viremia in HBsAg positive patients receiving dialysis.

RESULTS

Univariate analysis showed that AST and ALT values were significantly higher in HBsAg positive/HBV DNA positive than HBsAg negative patients on dialysis; AST, 22.86+/-31.34 vs. 14.19+/-9.7 IU/L (P=0.00001); and ALT, 25.07+/-41.59 vs. 13.9+/-41.59 IU/L (P=0.00001). In the subgroup of HBsAg positive patients, the frequency of detectable HBeAg in serum was 14.9% (7/47). The median value of HBV DNA in patients with detectable HBV DNA in serum was 2.160 x 10(3) copies/mL (range, 2.5 x 10(2)-4 x 10(6) copies/mL). HBsAg positive/HCV positive patients had higher aminotransferase activity than other subgroups (P=0.0001). Multivariate analysis showed a significant and independent association between detectable HBsAg/HBV DNA in serum and AST (P=0.00001) and ALT (P=0.0001) activity AST and ALT levels were lower in dialysis than healthy individuals--this finding persisted in age- and gender-matched comparisons.

CONCLUSIONS

The HBV viral load in HBsAg positive patients receiving maintenance dialysis is not high. HBsAg positivity with detectable HBV DNA in serum is a strong and independent predictor of raised aminotransferase activity among dialysis patients. HBsAg positive patients had greater aminotransferase activity than HBsAg negative individuals even if both the groups had mean aminotransferase levels within the normal range considered for healthy population. Clinical trials aimed at identifying the best cut-off value to enhance the diagnostic yield of AST/ALT for detecting HBV in dialysis population are under way.

[Identification of the cutoff value for serum alanine aminotransferase in hepatitis C screening of patients with chronic renal failure on hemodialysis]

The patients with chronic renal failure in hemodialysis present low levels of serum alanine aminotransferases. In order to establish a better cutoff value for ALT in hepatitis C screening of hemodialysis patients, the ALT levels were measured monthly in 235 patients, being excluded those that presented average above the upper limit of normality. The cutoff value was identified by construction of a ROC curve (receiver operating characteristic). Among 202 patients, 15 (7.4%) presented antibodies to hepatitis C virus (anti-HCV) and 187 (92.6%) were anti-HCV negative, with an ALT average of 0.7 and of 0.5 from ULN (p <0.0001), respectively. The better cutoff value for ALT was at 0.6 from ULN, with sensitivity of 67% and specificity of 75% in anti-HCV screening. These results suggest that ULN of ALT could be reduced for 60% from conventional limit, when we are evaluating patients with CRF in hemodialysis.

Presence and significance of TT virus in Danish patients on maintenance hemodialysis

OBJECTIVES

To determine the prevalence of TT virus (TTV) in a population of Danish hemodialysis patients and evaluate possible relations between TTV infection and elevated levels of C-reactive protein (CRP) and hypo-response to treatment with erythropoietin (EPO).

MATERIAL AND METHODS

Patients on maintenance hemodialysis at a single center were invited to participate. Demographic and clinical data were registered. Blood samples for virological and routine biochemical tests were drawn simultaneously. TTV DNA was detected using polymerase chain reaction (PCR). TTV viral load was estimated by means of semi-quantitative PCR. All patients were tested for hepatitis B, hepatitis C and GB virus C.

RESULTS

Of 252 patients, 204 (80.9%) gave their written informed consent to participate in the study. The prevalence of TTV was 68% and 50% of TTV-positive patients had a high TTV viral load. TTV-positive patients were significantly older than TTV-negative patients (p = 0.011). No relations were found between TTV infection and elevated levels of alanine aminotransferase (ALT) or CRP or hypo-response to EPO treatment. The mean hemoglobin concentration was 11.24 +/- 1.48 g/dl. Patients with a high TTV viral load had a lower level of hemoglobin (10.86 +/- 1.47 g/dl) than the others (p = 0.01). This trend suggested a positive relation between TTV infection and the number of blood transfusions. A restriction fragment length polymorphism assay suggested that patients were infected with different TTV strains.

CONCLUSIONS

TTV is common in patients on maintenance hemodialysis. The presence of TTV is associated with increasing age. Patients with a high TTV viral load had lower levels of hemoglobin than the others. TTV infection is not related to elevated levels of ALT or CRP or to hypo-response to EPO treatment.

Modified range of alanine aminotransferase is insufficient for screening of hepatitis C virus infection in hemodialysis patients

OBJECTIVE

A moderate increase in serum alanine aminotransferase (ALT) has been reported to be a helpful, low-cost tool for predicting viremia in anti-hepatitis C virus (HCV)-positive hemodialysis (HD) patients. This study focused on evaluating the effectiveness of a lowered normal serum ALT value as a screening method for HCV infection in HD patients.

MATERIAL AND METHODS

Serum ALT levels were compared with HCV virologic status in 125 patients on maintenance HD.

RESULTS

The prevalence of HCV antibodies was 23%. A total of 3.7% of viremic HD patients did not have a detectable antibody response. Using the conventional upper limit of normal for ALT of 37 IU, there was no significant difference in the frequency of elevated ALT levels between HCV RNA-positive and-negative patients. However, if the upper limit of normal for ALT was lowered to 27 IU, the difference was significant. Nevertheless, 60% of viremic patients still fell within the normal range.

CONCLUSION

Although inexpensive and widely available, the monitoring of serum ALT levels is not useful as a screening method for HCV infection in HD patients.

Impact of dedicated space, dialysis equipment, and nursing staff on the transmission of hepatitis C virus in a hemodialysis unit of the middle east

BACKGROUND

Infection with the hepatitis C virus (HCV) is endemic in hemodialysis (HD) units, especially in Middle Eastern countries. The meticulous isolation policy recommended for patients with the hepatitis B virus (HBV) in an HD unit resulted in a significant drop in HBV incidence globally. This study was developed to prospectively investigate the impact of an identical isolation policy on incidence of nosocomial HCV infection in this HD unit of the Middle East.

METHODS

In phase I of the study, we retrospectively reviewed the records of 189 patients with a mean age of 47.5 +/- 11.4 years (range, 15-85 years) who were receiving maintenance HD from December 7, 1995, to December 6, 2000, for the mean duration of 73 +/- 6.3 months (range, 3-144 months) to record the prevalence of HCV. Factors such as blood transfusions and dialytic age (time span that patient has received dialysis since its initiation) implicated in transmission of HCV in the HD unit also were recorded. Phase II involved stringent isolation of anti-HCV positive patients detected during phase I through provision of dedicated space, dialysis equipment, and nursing staff from December 7, 2000, to December 6, 2001. Liver function and anti-HCV tests were repeated for all the 198 patients every 6 months to identify new HCV seroconversions.

RESULTS

An HCV prevalence rate of 43.9% (83/189) and an annual HCV seroconversion rate of 6.8% were identified in this cohort. No significant association with blood tranfusion was observed. Eighty-three anti-HCV positive (43.9%) patients had a mean dialytic age of 48.5 +/- 14.2 months compared with 25.0 +/- 8.6 months among 106 (56.1%) anti-HCV negative patients (relative risk [RR], 1.89; 95% confidence interval [CI], 1.39-5.86; P <.001). Only 2 new HCV seroconversions (1.01% [2/198]) were identified.

CONCLUSIONS

Evidently, the sharing of facilities in a high-risk HD environment for a prolonged dialytic age facilitates the nosocomial transmission of HCV infection. A significant decline of annual seroconversion rate from 6.8% to 1.01% (odds ratio [OR], 7.535; 95% CI, 1.598-48.89; P <.005) suggests that a comprehensive, strictly enforced isolation policy for HCV-positive patients may play a significant role in limiting HCV transmission in HD units, just as it has in drastically reducing HBV transmission in these settings.

Decreased serum aminotransferase activity in patients with chronic renal failure: impact on the detection of viral hepatitis

Hepatitis C virus (HCV) infection is common in the dialysis population and patients with chronic renal failure (CRF) not requiring dialysis. HCV is the most important cause of chronic liver disease in dialysis patients; however, its role has been underestimated by the lower aminotransferase activity in the dialysis population. Aminotransferase activity in patients with CRF not requiring dialysis has not been adequately addressed to date. The aim of this study is to investigate whether serum aminotransferase levels in predialysis patients with CRF are less than those obtained in healthy individuals and dialysis patients. We also analyzed the potential association between serum aminotransferase activity and demographic, clinical, and biochemical parameters. Aspartate (AST) and alanine aminotransferase (ALT) activity was greater in antibody to hepatitis C (anti-HCV)-positive than anti-HCV-negative patients with CRF not requiring dialysis (AST, 32.3 +/- 19 versus 18.1 +/- 8 IU/L [P = 0.0001]; ALT, 32.9 +/- 28 versus 17.7 +/- 11 IU/L [P = 0.00001], respectively). Predialysis patients with CRF had lower AST and ALT activity in comparison to healthy individuals (AST, 19.7 +/- 11.2 versus 20.4 +/- 6.8 IU/L [P = 0.00001]; ALT, 19.5 +/- 15.1 versus 21.7 +/- 11.3 IU/L [P = 0.00001], respectively). The difference was much greater after correction for viral markers: AST and ALT levels in hepatitis B surface antigen (HBsAg)-negative anti-HCV-negative predialysis patients with CRF were less than those in the healthy population (AST, 17.9 +/- 8 versus 20.4 +/- 6.8 IU/L [P = 0.00001]; ALT, 17.5 +/- 10 versus 21.7 +/- 11.3 IU/L [P = 0.00001], respectively). Comparison of AST and ALT activity between age-matched healthy and predialysis seronegative CRF groups showed lower AST and ALT values in the study population. HBsAg-negative anti-HCV-negative dialysis patients had lower AST and ALT activity than seronegative predialysis patients with CRF (AST, 16.6 +/- 11.6 versus 17.9 +/- 8 IU/L [P = 0.01]; ALT, 16.3 +/- 9.4 versus 17.5 +/- 10 [P = 0.041], respectively). Multivariate analysis in the predialysis CRF population showed an independent association between AST (P = 0.00001) and ALT (P = 0.00001) activity and anti-HCV positivity, and age was negatively linked to AST (P = 0.011) and ALT levels (P = 0.001). AST level was negatively related to serum creatinine level (P = 0.0001). In conclusion, HCV infection causes significant liver injury in predialysis patients with CRF. These patients have decreased aminotransferase activity compared with the general population. Dialysis patients show lower aminotransferase activity than predialysis patients with CRF. Because serum aminotransferase levels are commonly used to screen for liver disease in the dialysis and predialysis CRF population, recognition of liver damage may be hampered by the reduction in aminotransferase values in these patients. Studies aimed to clarify the pathogenesis of this phenomenon are in progress.

[Antibodies to hepatitis C virus in patients undergoing hemodialysis in Salvador, BA, Brazil]

BACKGROUND

Hepatitis C infection in hemodialysis units has been evaluated in different geographic regions.

AIMS

The prevalence of anti-HCV in patients undergoing hemodialysis program in the city of Salvador, State of Bahia, Brazil, was studied and its association with transfusions, duration of hemodialysis and ALT elevation.

METHOD

During a period of 17 months, all patients undergoing dialytic treatment, were evaluated. The total number of patients was 395, all of whom completed a questionnaire and provided serum samples for laboratory analysis. Serological levels were measured for ALT and the samples were tested for anti-HCV using ELISA II with a further confirmation using RIBA III.

RESULTS

Anti-HCV was positive in 23.8% (94/395). The presence of transfusions was associated with anti-HCV and as the number of transfusions used increased, so did the frequency of anti-HCV. Of the patients who never received transfusions, 12.5% (6/48) were anti-HCV positive. The duration of dialytic treatment lasted from 53.44 +/- 36.45 months in the anti-HCV positive group and 22.10 +/- 22.75 months for the group testing negative. ALT elevation was more frequent in the anti-HCV positive group. Positivity for the RIBA III fractions was 79.8%, 100%, 80.9% and 52.1%, for c100-3, c33, c22 and NS5, respectively. The anti-NS5 was even less frequent in the group with elevated ALT.

CONCLUSIONS

The prevalence of anti-HCV in patients undergoing chronic hemodialysis in Salvador, Bahia, is elevated and it is associated with transfusions, a longer duration of dialytic treatment and ALT elevation.

Phylogenetic evidence, by multiple clone analysis of hypervariable region 1, for the transmission of hepatitis C virus to chronic haemodialysis patients

We analysed hepatitis C virus (HCV) sequences to determine whether nosocomial transmission of HCV occurred in a haemodialysis unit. Twenty patients positive for serum HCV RNA were investigated. All were undergoing haemodialysis therapy in the same room. The hypervariable region 1 (HVR1) sequence of HCV was amplified and multiple clones sequenced. Phylogenetic analysis of these sequences revealed five genetic clusters consisting of HCV isolates from 11 of the 20 patients. In addition to two genetic clusters of HCV isolates from the four currently seroconverting patients and another patient who had been persistently infected, we identified three other phylogenetic relationships in HCV isolates from six patients. The patients grouped into the same cluster received haemodialysis individually on the same shift and/or side-by-side. Phylogenetic analysis of HCV HVR1 sequences corroborated the patient-to-patient HCV transmission suggested by an epidemiological study and that unrecognized transmission of HCV occurs in the dialysis room. Our multiple clone analysis of HCV isolates provides detailed information on nosocomial transmission of HCV. Transmission occurs more frequently when treatment is performed at the same time than in consoles located close to each other.

Occasional infection of hepatitis C virus occurring in haemodialysis units identified by serial monitoring of the virus infection

To examine whether hepatitis C virus (HCV) infection still occurs in haemodialysis units even after a decrease in the number of blood transfusions and in those contaminated with HCV, we tested anti-HCV antibodies and HCV RNA in 142 patients from Japanese haemodialysis units, and examined the serial prevalence of anti-HCV antibodies in 86 patients from 1992 to 1997. A high prevalence of HCV infection was observed: 34 (23.9%) and 38 (26.8%) of the 142 patients were positive for serum anti-HCV antibodies and HCV RNA, respectively. These positive rates were related to the duration of haemodialysis. We found that five patients treated in the same unit seroconverted from 1993 to 1995. Four of the five patients had been treated at the same shift and were affected at the same time. Phylogenetic analysis of the hypervariable region 1 (HVR1) sequence of HCV from serum of these patients showed that three of the four patients' sequences were phylogenetically clustered and that two of the three were closely related. Thus, an occasional transmission of HCV occurred in the haemodialysis unit. The universal precautions by staff such as carefully changing gloves may be important in inhibiting spread of HCV because no instances of infection have been seen since the instigation of educational measures for unit staff.

Serotyping strip immunoblot assay for assessing hepatitis C virus strains in dialysis patients

Recent accumulated evidence shows that dialysis patients are a high-risk group for hepatitis C virus (HCV) infection. Assessment of HCV genotype distribution among dialysis patients may be important because specific viral genotypes are associated with different clinical manifestations, disease progression, and response to antiviral therapy. However, polymerase chain reaction-based methods are cumbersome and unsuitable for analyzing large cohorts of dialysis patients with HCV. Instead, this information can be obtained by using a novel recombinant immunoblot assay (RIBA) recently developed for determining HCV serotype. The RIBA HCV serotyping strip immunoblot assay (SIA; Chiron Corporation, Emeryville, CA), is based on an immunoblot strip with five lanes of immobilized serotype-specific HCV peptides from the nonstructural (NS4) and core regions of the genomes of HCV types 1, 2, and 3. HCV serotype is deduced by determining the greatest intensity of reactivity to the NS4 serotype-specific HCV peptide band in relation to the internal control band (human immunoglobulin G) intensity on each strip. HCV core peptide reactivity is used only in the absence of NS4 reactivity. We compared RIBA HCV serotyping SIA with genotyping using sera from a large (n = 107) cohort of HCV-infected patients undergoing chronic hemodialysis (HD). We successfully serotyped 79 of 107 patients (74%) undergoing HD. We found a remarkable concordance (65 of 70 results; 93%) between RIBA HCV serotyping SIA and genotyping (line probe assay [LiPA]) techniques (kappa = 0.786) with sera from viremic patients infected with a known genotype. Only 5 of 70 patients (7%) had apparently discordant results. In a subset of patients (28 of 107 patients; 26%) not typed by RIBA HCV serotyping SIA, most (24 of 28 patients; 86%) were successfully genotyped by LiPA technology. It was possible to assess serotype reactivity in some patients (9 of 107 patients; 7%) who could not be genotyped. The distribution of HCV serotypes was associated with the antibody response against HCV proteins and the patterns of reactivity by RIBA HCV 2.0 SIA. In conclusion, (1) we found good agreement between serotyping and genotyping methods in our large cohort of dialysis patients infected with HCV; (2) the impaired immunocompetence conferred by uremia may limit serotyping analysis in some HCV-infected patients undergoing HD; (3) RIBA HCV serotyping SIA may be useful in tracking transmission routes for HD patients who cleared the virus and have only anti-HCV antibody; and (4) the distribution of HCV serotypes was associated with the antibody response against HCV proteins and the patterns of reactivity by RIBA HCV 2.0 SIA. Assessment of HCV strains appears to be very useful in the routine clinical activity of nephrologists within HD units because consistent biological differences among HCV strains exist. RIBA serotyping SIA is a simple, inexpensive, and highly reproducible assay to obtain information about HCV types in the HD setting.

Molecular epidemiology of an outbreak of HCV in a hemodialysis unit: direct sequencing of HCV-HVR1 as an appropriate tool for phylogenetic analysis

Infection with hepatitis C virus (HCV) is still a serious problem in hemodialysis patients, despite screening of blood products for anti-HCV antibodies. The prevalence of HCV in HD patients is between 15% and 30% in Germany. We report the molecular epidemiology of an HCV outbreak in a hemodialysis unit in 1997 is determined. HCV hypervariable region 1 (HVR1) was amplified from serum samples of 19 patients by polymerase chain reaction (PCR) and sequenced directly. In addition, HCV isolates from 3 of these 19 patients were cloned and sequenced. 14 newly infected patients and two patients, who had been infected for several years had very closely related HCV isolates. Unrelated HCV isolates as well as sequences obtained from an HCV outbreak in a plasmapheresis center were found in different, distantly related branches. These findings provide strong evidence for nosocomial transmission of the virus, despite following strict general hygiene precautions. The production of anti-HCV antibody was delayed significantly or seroconversion did not occur at all during the period of observation in 8 out of 14 newly infected HCV RNA positive patients. Close-meshed reverse transcription-polymerase chain reaction (RT-PCR) analyses on apparently non infected patients within hemodialysis units and upon admission of new patients is strongly recommended for the early detection and prevention of outbreaks of HCV.

Biological dynamics of viral load in hemodialysis patients with hepatitis C virus

The biological dynamics of hepatitis C virus (HCV) viremia in uremic patients with chronic infection have not been fully characterized. We prospectively studied fluctuations of HCV-RNA in sera from 52 patients with end-stage renal disease who were undergoing maintenance hemodialysis (HD) and had chronic HCV infection. We measured HCV viremia monthly over the course of 13 months with the branched-chain DNA (bDNA) signal amplification assay and prospectively analyzed liver function, expressed by monthly serum aspartate (AST) and alanine aminotransferase (ALT) determinations. We observed three different patterns of HCV viremia: (1) patients persistently positive by bDNA assay (persistent viremia; 23 of 52 patients; 44%), (2) individuals with alternatively positive and negative results (intermittent viremia; 17 of 52 patients; 33%), and (3) patients persistently negative by bDNA assay (12 of 52 patients; 23%). The HCV viral load over the follow-up was greater among patients with persistent compared with intermittent viremia (persistent, 31.7 x 10(5) Eq/mL; range, 6.3 x 10(5) to 16.03 x 10(6) Eq/mL versus intermittent, 10.4 x 10(5) Eq/mL; range, 1.1 x 10(5) to 9.4 x 10(6) Eq/mL; P = 0.0001). In addition, patients with persistent viremia had over time greater AST and/or ALT activities than the intermittent group (AST: persistent, 26.5 IU/L; range, 9.6 to 73.7 IU/L versus intermittent, 21.3 IU/L; range, 8 to 56.8 IU/L; P = 0.001 and ALT: persistent, 14.7 IU/L; range, 3.7 to 57.9 IU/L versus intermittent, 10.9 IU/L; range, 2.3 to 52.1 IU/L; P = 0.001). In the group with persistent viremia, the mean difference between maximum and minimum values of HCV-RNA observed in each individual patient was 2.09 +/- 0.7 natural logarithm (Log(n)) and in intermittent viremic patients, 1.55 +/- 1 Log(n) (P = 0.045). The HCV load at study entry (19.4 x 10(5) Eq/mL) was rather low and did not change versus the end of follow-up in all patients (P = not significant [NS]). In the entire group, the fluctuations in HCV-RNA levels over time between and within individuals were not significant (P = NS). No difference in variability of HCV-RNA values over time between patients infected with different HCV genotypes was seen. In conclusion, three different patterns of HCV viremia in HD over time were assessed; one third of viremic patients had intermittent viremia, and those patients had less HCV-RNA, enzyme-linked immunosorbent assay, and aminotransferase activity than did patients with persistent HCV load. Larger fluctuations in HCV RNA levels occurred in patients with persistent than with intermittent HCV viremia. However, the viremic HCV load was low and relatively stable over a 13-month follow-up in our population. Studies with longer observation periods are warranted to understand fully the natural history of HCV in these immunosuppressed individuals.

TT virus infection in hemodialysis patients

OBJECTIVE

Recently, TT virus (TTV), associated with posttransfusion hepatitis, was discovered. Prevalence of TTV infection in maintenance hemodialysis (HD) units and its pathogenicity to liver was investigated.

METHODS

A total of 115 patients on HD were assessed for presence of serum TTV. DNA was purified from sera, and nested polymerase chain reaction was done for the detection of TTV DNA.

RESULTS

TTV was detected in 59 patients on HD (51.3%), as compared with healthy blood donors (15 of 91 [16.5%], p < 0.0001). Serum HCV RNA and HBs antigen were positive in 16 and three patients, respectively. The prevalence rate of TTV was already 58.3% in the patients on HD for only 1 yr, and did not change according to the duration of HD until 15 yr on HD. TTV was positive in 51.2% (43 of 84) of the patients with history of blood transfusion, and in 51.6% (16 of 31) of those without it. In HCV-negative patients, alanine aminotransferase (ALT) levels of TTV-positive patients were similar to those of TTV-negative patients. Contrarily, in HCV-positive patients, ALT levels were more frequently > or =15 IU/L in TTV-positive patients (14 of 18) than in TTV-negative patients (five of 15) (p < 0.05).

CONCLUSIONS

TTV infection is remarkably prevalent in patients on HD and in healthy blood donors. It is suggested that TTV generally does not cause liver disease by itself, but there remains the possibility that TTV may aggravate liver disease caused by HCV.

Validation of self-reported transfusion histories in renal dialysis patients

The purpose of this analysis was to assess the validity of self-reported transfusion histories in dialysis patients. Using data from a cross-sectional study of a dialysis population being investigated for hepatitis C virus (HCV) infection, the correspondence between self-reported transfusion history and transfusion records was explored. Demographic data and dialysis histories were examined in relation to the accuracy of self-reports. Overall, the questionnaire data and the blood bank records agreed for 89% of participants. The Kappa statistic was 0.72 (95% CI: 0.61, 0.83) indicating an acceptable level of agreement. The effect of non-differential exposure misclassification on the risk estimates for transfusion history as a determinant of HCV infection is demonstrated. Exploring the discrepancies between self-reports and documented transfusion histories underlines the need to communicate clearly medical interventions in chronically ill patients. Additionally, it suggests that studies into transfusion-acquired blood-borne pathogens should use all available information sources to establish exposure.

Blood-borne virus infections in dialysis units--a review

Hepatitis outbreaks in haemodialysis unit patients and staff were reported in the late 1960s. In 1972, the Rosenheim report in the UK established guidelines which included routine tests for hepatitis B surface antigen and isolation facilities for dialysing patients with hepatitis B virus which resulted in a dramatic fall in cases of hepatitis. However, since these guidelines were introduced, other blood-borne viruses, notably HCV and HIV have been discovered, and failures of infection control practices still lead to outbreaks of HBV in haemodialysis units. The prevalence of HCV in dialysis patients varies considerably throughout the world, with reported prevalence ranging from 3.9% to 71%. The number of blood transfusions and the length of time on dialysis have consistently been associated with HCV prevalence. Several reports provide evidence of patient-to-patient HCV transmission with environmental blood contamination the most significant factor in intra-unit transmission. There is no evidence that HCV has been transmitted by re-use of dialysis machines but being dialysed next to an HCV positive patient is associated with a significant risk of HCV acquisition. Several studies have shown that dialysing HCV positive patients in a separate unit or in a defined sector of a dialysis unit significantly reduces nosocomial HCV infection. HGV is prevalent in dialysis units where there is evidence of transmission to patients but no evidence of associated symptoms. HIV is infrequently transmitted in dialysis units and several units treating many HIV-positive patients have shown no evidence of transmission. Careful attention needs to be paid to infection control procedures and regular virological testing.

Renal manifestations of hepatitis C infection

Hepatitis C is an important cause of renal disease, and renal complications may be the presenting manifestation of hepatitis C infection. About half of patients present with evidence of renal insufficiency, and up to one quarter present with nephrotic syndrome. Others present with proteinuria or evidence of diminished renal function. The pathogenesis of hepatitis C-associated renal disease remains incompletely defined, but most evidence suggests that glomerular injury results from deposition of circulating immune complexes in the subendothelium and mesangium. Membranoproliferative glomerulonephritis, with or without cryoglobulinemia, is the most common renal lesion. Interferon alpha-2b is currently the treatment of choice. However, success is limited, with many patients failing to respond or suffering relapse upon discontinuation of therapy. Studies of newer treatment modalities, such as longer courses of interferon or the use of ribavirin or immunosuppressive agents, are underway. Hepatitis C-associated renal disease may progress to end-stage renal failure requiring dialysis in about 10% of patients.

Hepatitis C virus infection in four haemodialysis units of southern Italy: epidemiological report

The haemodialysis patients are an high risk population for hepatitis viral infections. While the incidence of HBV has decreased worldwide, HCV is now the major cause of viral infection in these patients. The aim of our study was to define a complete map of patients undergoing routine replacement therapy by haemodialysis in the province of Foggia, Southern Italy, who were HCV Ab positive, the presence of viraemia and their genotypes; moreover, we investigated the probable factors involved in determining the infection as well as the means of prevention.

MATERIALS AND METHODS

We enrolled 330 patients treated in four haemodialysis centres (DC) and six secondary units; mean age was 57 years and mean duration of dialysis 76 months. Samples were drawn to determine cytolysis indexes and the HCV Ab status; in HCV positive patients, we also looked for viraemia and HCV genotypes. Data were analysed by a transversal cross-section study.

RESULTS AND CONCLUSIONS

Prevalence of HCV infection was 0.43 (males 0.45, females 0.42). The risk of contracting the infection was shown to be significantly different in the various DCs and did not seem to be related to the severity of the preventive measures. There was no significant difference between the various DCs in the comparison between the odds of HCV-RNA+ and HCV-RNA- patients. No significant prevalence of a given genotype emerged from a cross-sectional study related to the comparison between different genotypes. Moreover, transfusions of blood products seemed to have no significant relation to HCV infection. Finally, patients treated with haemodialysis for more than 36 months run a seven time greater risk of contracting HCV infection.

Hepatitis B vaccine in hemodialysis patients with hepatitis C viral infection

Patients on hemodialysis therapy are at a relatively high risk of exposure to hepatitis B virus (HBV) infection. The prevalence of hepatitis C virus (HCV) infection is even higher and was reported as 33.2% in Taiwan. Although the efficacy of hepatitis B vaccine was well documented, the vaccination schedule in hemodialysis patients is not clearly defined. And under such a high prevalence of HCV infection, little is known about the influence of HCV imposing on HBV vaccination. We studied 50 chronic hemodialysis patients who were serologically negative for the hepatitis B surface antigen (HBsAg), the antibody to the hepatitis B surface antigen (anti-HBs) and the antibody to the hepatitis B core antigen (anti-HBc); 26 of them were positive for the antibody to hepatitis C virus (anti-HCV) test. Recombinant hepatitis B vaccine (Engerix-B) 40 micrograms per dose was administered by the intramuscular route at deltoid region at 0, 1, 2, 6 and 12 months respectively to all the patients. Forty-six patients had completed the study. The effective seroconversion rate (serum anti-HBs titer > 10 mIU ml-1) at 1 month after the final vaccine was 76.1% (35/46). The effective conversion rates of the anti-HCV(+) group to the anti-HCV(-) were 75% versus 77.3% (P = 0.857). Geometric mean anti-HBs titers were 177.67 mIU ml-1 versus 189.28 mIU ml-1 (P = 0.867). Our results showed that five-dose injections of HBV vaccine do not present a superior outcome to the four-dose regimen comparing to published data. The status of positivity of anti-HCV do not pose an suboptimal effect on HBV vaccination of hemodialysis patients.

The long-term course of hepatitis C after kidney transplantation

Patients with chronic hepatitis run the risk of developing progressive liver disease during immunosuppressive therapy after kidney transplantation. To determine the impact of chronic hepatitis C on morbidity and mortality we analyzed 162 anti-HCV positive of 1241 renal-grafted patients (prevalence 13.1%; 84.9% HCV RNA positive) regularly surveyed in our outpatient clinic between 1992 and 1994. The mean age at transplantation was 44.5 (6-69) years, and follow-up after grafting was 7.4 (0.1-23.9) years. The immunosuppressive regimen and frequency of rejection episodes in HCV-infected patients were comparable to the total population. Only 4.3% (5/117) of the anti-HCV positive, HBV negative patients living with functioning grafts developed a markedly compromised liver function. Fifteen (9.3%) of the HCV-infected patients died, but none suffered from posthepatitic cirrhosis. An additional retrospective analysis of causes of death after transplantation prior to 1992 revealed that liver disease had only been responsible for 2% of the deaths (7 of 324) in the HBsAg negative population (n= 1901). In contrast, the predominant cause of death in the HBsAg positive population (n=76) was posthepatitic cirrhosis in 58% (15 of 26). Thus, kidney transplantation in patients with replicative hepatitis C and normal liver function appears to be justified because of low early and late morbidity and mortality due to chronic liver disease. HBV infection and hemosiderosis substantially increase the risk of chronic liver disease in renal transplant recipients with hepatitis C.

Hepatitis C in dialysis patients

Patients on hemodialysis have a higher prevalence of hepatitis C (HCV) infection compared with the general population. Several factors have been associated with an increased risk of HCV infection in hemodialysis patients, including number of blood transfusions, duration of hemodialysis, previous transplantation, intravenous drug abuse, male gender, and in-center hemodialysis. In addition, there is mounting evidence to suggest nosocomial transmission within hemodialysis units. Although the precise modes of transmission have not been identified, breakdown in standard infection control practices, physical proximity to an infected patient, and sharing of dialysis machines are possible causes. Nonetheless, at the present time, the Centers for disease Control and Prevention (CDC) does not recommend dedicated machines, patient isolation, or a ban on re-use in hemodialysis patients with HCV infection. Consequently, strict adherence to universal precautions and careful attention to hygiene are recommended to reduce the transmission of HCV in dialysis units.