Should Hemodialysis Patients with Hepatitis C Virus Antibodies Be Isolated?

Infection with hepatitis C virus in hemodialysis patients: An overview of the diagnosis and prevention rules within a hemodialysis center (Review)

Increase in the number of patients with chronic kidney disease (CKD) calls for improved management of these patients. In stage 5 CKD, when the initiation of renal replacement therapy (RRT) becomes necessary, there is an increase in the infection risk of the patients and immunological tests for hepatitis C virus (HCV) detection turn positive at an alarmingly higher rate compared to general population. With the introduction into clinical practice of diagnostic tests, the increased prevalence of HCV among CKD patients has been known since the 1990s. Also, the negative impacts of HCV infection on CKD evolution as well as the unfavorable evolution of grafts received by HCV infected patients are known. Chronic hemodialysis patients are a category of patients whose risk of HCV infection is substantial. Currently, in the hemodialysis centers, at the base of the transmission of HCV infection there are a multitude of factors. Infection with HCV has a different impact on patient with end-stage renal disease (ESRD). Comorbidities in this case have significant sources of mortality and morbidity. It was proven that the post transplantations problems were prevented and mortality was reduced for patients who were diagnosed with HCV and in whom the infection was treated before the kidney transplant (KT). Consequently, early detection of the infection and the application of specific treatment has a considerable impact on the outcome of the patients. Another important component of the management of HCV infection in the chronic hemodialysis patients is the prevention of the infection transmission by applying specific methods.

Prevalence, incidence, and risk factors for hepatitis C virus infection in hemodialysis patients

Hepatitis C virus (HCV) infection is common in dialysis patients and is associated with increased morbidity and mortality. We used the Dialysis Outcomes and Practice Patterns Study (DOPPS, 1996-2015) to assess trends in the prevalence, incidence, and risk factors for HCV infection as defined by a documented diagnosis or antibody positivity. Among prevalent hemodialysis patients, HCV prevalence was nearly 10% in 2012-2015. Prevalence ranged from 4% in Belgium to as high as 20% in the Middle East, with intermediate prevalence in China, Japan, Italy, Spain, and Russia. HCV prevalence decreased over time in most countries participating in more than one phase of DOPPS, and prevalence was around 5% among patients who had recently (<4 months) initiated dialysis. The incidence of HCV infection decreased from 2.9 to 1.2 per 100 patient-years in countries participating in the initial phase of DOPPS. Although most units reported no seroconversions, 10% of units experienced 3 or more cases over a median of 1.1 years. High HCV prevalence in the hemodialysis unit was a powerful facility-level risk factor for seroconversion, but the use of isolation stations for HCV-positive patients was not associated with significantly lower seroconversion rates. Overall, despite a trend toward lower HCV prevalence among hemodialysis patients, the prevalence of HCV infection remains higher than in the general population. Combined with a high prevalence of HCV infection among patients with Stage 5 CKD, high rates of HCV seroconversion in a subset of hemodialysis units may contribute to this disparity.

The prevention of hepatitis C virus transmission to hemodialysis patients and staff members

In this review article, we cover 4 topics very relevant to those involved in the care of hemodialysis (HD) patients and in the management of a HD unit. We start with an overview of the progress made over the last 25 years to reduce hepatitis C virus (HCV) transmission in HD. Next, we discuss the potential strategies to prevent the residual ongoing transmission of HCV to HD patients. Third, we discuss the actions to be taken if a seroconversion for HCV is nevertheless detected in a HD patient. Finally, we briefly discuss how best to protect HD staff members from occupationally acquired HCV infection.

Prevention of Nosocomial Transmission of Hepatitis C Infection in a Hemodialysis Unit. A Prospective Study

Hepatitis C virus (HCV) infection in hemodialysis patients can be transmitted by transfusions and nosocomially. A high prevalence of HCV infection, over 50%, was demonstrated in our hemodialysis (HD) unit. In order to prevent the nosocomial spread of HCV infection in the HD unit a prospective study was begun separating anti-HCV positive patients from the negative ones. A total of 170 patients (83 anti-HCV positive) started this study in September 1994 and were followed for 4 years. A separate room and dedicated equipment were assigned to anti-HCV positive and anti-HCV negative patients. Of those 170 patients there were 15 hepatitis B virus (HBV) positive patients, 5 of whom were anti-HCV positive, who were treated in a separate room on dialysis equipment for anti-HCV positive or negative patients. Application of general precautions, as recommended by the Center for Disease Control and Prevention (CDC), was reinforced. During the first 12 weeks after implementing the precautions seven more anti-HCV positive patients were detected, and by December 1995 another two HCV infected patients were found. The follow-up included all changes in HD population treated until the end of 1998. The incidence of seroconversion to HCV was 12.9% in 1995, 7.1% in 1996, 5.0% in 1997, and 6.6% in 1998. The higher incidence of seroconversion in September to November 1994 was probably due to the nosocomial infection being in the incubation period at the time of isolation.

This prospective study in a large HD unit with a high prevalence of HCV infection demonstrates a relatively successful prevention of HCV spread. Procedure-related transmission of HCV in hemodialysis could be prevented by rigorous application of universal precautions as recommended by the CDC. As a second line of prevention, in highly burdened dialysis centers, segregation of HCV positive patients can help control nosocomial transmission.

Hepatitis C virus genotype does not affect patient survival among renal transplant candidates. The New England Organ Bank Hepatitis C Study Group

BACKGROUND

Patients with end-stage renal disease (ESRD) are at increased risk for infection with different hepatitis C virus (HCV) genotypes and multiple genotype infections. However, to date, the effect of the type and number of infecting HCV genotypes on survival among ESRD patients has not been carefully examined, and this was the objective of this study.

METHODS

Sera from patients on the renal transplant waiting list at the New England Organ Bank between November 1986 and June 1990 were tested for anti-HCV using a third-generation enzyme-linked immunosorbent assay. All anti-HCV-positive serum samples were tested for HCV RNA by reverse transcriptase "nested" polymerase chain reaction (PCR) with primers derived from the highly conserved 5'UTR region of the HCV genome. HCV genotypes were determined by restriction fragment length polymorphism of the 5'UTR PCR product. The duration of follow-up was calculated from the date of the first available serum specimen until death, loss to follow-up, or December 31, 1995, whichever occurred earlier. Two separate multivariate models were constructed: one to examine the impact of HCV genotype on mortality and the other to examine the impact of the single versus mixed infection on mortality. In both models, the independent variables were HCV genotype and transplantation. The HCV genotype was treated as a time-independent (baseline) variable. Transplantation was treated as a time-dependent variable in which the status changed after transplantation.

RESULTS

HCV RNA was detected by PCR in 224 patients (81%) in whom sera were available. Complete clinical data on baseline covariates, subsequent transplantation, and mortality were available in 180 patients (80%), and these patients constituted the final study cohort. HCV genotypes 1a and 1b were the two most common genotypes encountered and were found in 60 and 24% of the patients, respectively. One hundred and sixty-two (90%) patients were infected with a single HCV single genotype, 16 patients (9%) with two genotypes, and two patients (1%) with three genotypes. Among the 180 patients in the final study cohort, 86 (48%) underwent transplantation, and 66 (37%) patients died during follow-up. Compared with patients infected with HCV genotype 1a, the relative risk (RR) of death from all causes was not significantly increased among patients infected with genotype 1b (RR = 1.02, 95% CI, 0.55 to 1.89) or other genotypes (RR = 1.08, 95% CI, 0.50 to 2.30). Likewise, compared with patients with a single infection, the RR of death among patients with mixed infection (RR = 1.18, 95% CI, 0.52 to 2.66) was not significantly increased.

CONCLUSIONS

The results of this study suggest that the type and number of HCV genotypes may not have a significant impact on survival among ESRD patients.

Universal precautions prevent hepatitis C virus transmission: a 54 month follow-up of the Belgian Multicenter Study. The Universitaires Cliniques St-Luc (UCL) Collaborative Group

The isolation of anti-hepatitis C virus (HCV) in hemodialyzed (HD) patients has been repeatedly advocated to prevent nosocomial HCV transmission. We evaluated the incidence of seroconversion for HCV in Belgian HD patients, and demonstrate the complete prevention of HCV transmission by adherence to the universal precautions advocated by the Centers for Disease Control (Atlanta, GA, USA). All (N = 963) HD patients from 15 units, none of which isolates anti-HCV positive patients, were tested by a second or third generation enzyme-linked immunosorbent assay (with confirmation by a second- or third-generation recombinant immunoblot assay or the polymerase chain reaction) every 18 months from May 1991 to November 1995. Follow-up was available in 488 patients (drop-outs resulting from death or transplantation mainly). The yearly incidence of seroconversion for HCV over the initial 18 months was 1.41%, with evidence suggestive of nosocomial HCV transmission. Universal precautions were therefore reinforced. The incidence of seroconversion subsequently fell to 0.56% and 0%, respectively (P = 0.014), despite the facts that the average transfusion load and the proportion of patients with dialyzer reuse or with monitors disinfected after each session did not change significantly. We conclude that the strict enforcement of universal precautions fully prevents HCV transmission to HD patients. The isolation of anti-HCV positive patients is not warranted.

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.

Undiagnosed hepatitis C virus infection in hemodialysis patients: value of HCV RNA and liver enzyme levels

At present, routine screening for hepatitis C virus (HCV) infection is based on the detection of antiviral antibodies. Underdiagnosis of HCV infection by using HCV antibody tests, however, still occurs. Additional diagnostic means are provided by the polymerase chain reaction (PCR). The measurement of aminotransferase (ASAT and ALAT) has served as an auxiliary, less specific test. The present research aimed to design practical and low cost strategies to diminish underdiagnosis of HCV infection in dialysis patients. With this purpose in mind, we examined whether aminotransferases values in HCV antibody-negative patients could be related to undiagnosed HCV infection, by using HCV RNA testing by PCR as the gold standard. In 112 hemodialysis patients, we found 78 negative and 34 positive for HCV antibodies. A major finding was that 222 (28.2%) out of the 78 HCV antibodies-negative patients had positive HCV RNA by PCR. In repeated samples taken at six months follow-up from 19 out of these 22 patients, only one of them was positive for anti-HCV antibodies; moreover, a positive HCV RNA by PCR was confirmed in 13 (68.5%) of them. Within the HCV antibody-negative group, the mean values of ASAT, ALAT and gammaglutamiltransferase were higher (P < 0.001, P < 0.001 and P < 0.02, respectively) in the HCV PCR-positive versus the HCV PCR-negative patients. No significant differences were found in the liver enzyme values between the HCV antibody-negative, HCV RNA positive and the HCV antibody positive, HCV RNA positive individuals. Histological samples from two HCV RNA positive, HCV antibody-negative patients disclosed the presence of a mild liver disease. In conclusion, the present study demonstrates the critical importance of HCV RNA determination by PCR in hemodialysis patients who have no detectable circulating antibodies against the HCV. Furthermore, in conditions in which PCR technology is not readily available, we have established that the existence of a moderate increase of aminotransferases is a helpful clue to detect patients with absent HCV antibodies, and might represent an useful, low cost tool for HCV screening in dialysis patients.