Behavior of antibody profile against hepatitis C virus in patients on maintenance hemodialysis

Routine serologic testing for hepatitis C virus infection should be instituted among dialysis patients

Since the cloning of hepatitis C virus (HCV), a number of serologic and virologic tests for detecting infections with this virus have been made available for clinical practice. This led to the recognition of HCV as a major health hazard in hemodialysis (HD) centers. Yet the nephrology community has not been offered explicit recommendations about routine serologic testing for HCV of dialysis patients and consequently has remained unclear and divided about the utility of this testing. This review presents evidence in support of instituting routine serologic testing for HCV among dialysis patients. It concludes that because of the peculiar features of HCV infection in HD patients, serologic testing for HCV is the only means for unequivocal diagnosis of hepatitis C and an irreplaceable instrument for monitoring the incidence and the prevalence of the infection in this population. Serologic surveillance for HCV infection is crucial for identifying the association of new cases of HCV infection with potential risk factors for HCV transmission, particularly nosocomial, that can be modified in a way to prevent further dissemination of the virus. Data collected from routine serologic testing for HCV will undoubtedly improve our understanding of the epidemiology of HCV in the dialysis population and will provide a strong foundation for developing preventive measures and infection control strategies that are highly effective in controlling HCV infection. Routine serologic testing for HCV is also of direct benefit to the individual patient since establishing the HCV serologic status of each patient is important for optimizing patient care.

Hepatitis C virus infection among chronic dialysis patients in the south of France: a collaborative study

During the last quarter of 1992, 984 patients from 13 dialysis centers in the Provence-Alpes-Côte-d'Azur region in France participated in a multicenter cross-sectional study to determine the prevalence, the risk factors, and the clinical consequences of infection by the hepatitis C virus (HCV). Serum samples were tested for anti-HCV antibodies using second-generation enzyme-linked immunosorbent assay (ELISA). In the case of a positive result, a combination test was performed using second-generation recombinant immunoblot (RIBA) or direct detection of HCV-RNA by nested polymerase chain reaction (PCR). Collected data included the patient's age, gender, cause of the kidney disease, type of dialysis treatment, number of years on dialysis, weekly dialysis time, drug addiction, co-infection with hepatitis B virus and human immunodeficiency virus (HIV), number of kidney transplants, number of blood transfusions, and history of acute or chronic hepatitis. Chronic HCV infection was detected in 232 (23.6%) patients, whereas only 71 (7.2%) were infected by HBV. Logistic-regression analysis showed that HCV infection was associated with dialysis over a long period, numerous blood transfusions, female gender, kidney grafts, HBV infection, hemodialysis, and acute as well as chronic hepatitis. Multiple-correspondence analysis confirmed that the contamination was both transfusional and nosocomial. These results underscore the need for a strict compliance with "universal precautions" (Centers for Disease Control [CDC], Atlanta) in dialysis units and raise the question as to whether anti-HCV-positive patients should be isolated.

Hepatitis C virus: the nephrologist's view

The last 4 years have been a period of rapid expansion in our understanding of both the molecular biology and clinical significance of hepatitis C virus (HCV) infection. Initial studies using first-generation enzyme-linked immunosorbent assays suggested that the end-stage renal disease population had an exceptionally high prevalence of anti-HCV compared with asymptomatic healthy blood donors. Subsequent analyses with second-generation assays and polymerase chain reaction techniques to detect viremia confirmed these earlier studies. Considering the prevalence of HCV within the dialysis population, it comes as no surprise that several studies confirmed HCV as the leading cause of non-A, non-B hepatitis among renal allograft recipients. Furthermore, transmission of HCV by transplantation of a kidney from an HCV-infected organ donor has been unequivocally demonstrated. The natural history of HCV infection in the immunosuppressed allograft recipient and its impact on long-term patient outcome are still being analyzed. Finally, HCV has been associated with essential mixed cryoglobulinemia and several histologic patterns of immune complex glomerulonephritis, including membranous and membrano-proliferative glomerulonephritis. Although HCV antigen-antibody complexes have not been demonstrated in the kidney, the marked decrease in proteinuria following clearance of HCV RNA with interferon alpha-2b therapy suggests an etiologic role for HCV in these glomerular diseases. Furthermore, the demonstration of HCV RNA in the cryoprecipitate of patients with essential mixed cryoglobulinemia and a beneficial response to treatment with interferon alpha-2b also suggest a role for HCV in the pathogenesis of these clinical syndromes.

Seroprevalence of HCV, HAV, HBV, HDV, HCMV and HIV in high risk groups/Frankfurt a.M., Germany

During the period from August 1991 to April 1993, serum samples originating from different risk groups were tested for antibodies against hepatitis C virus (HCV), using a second-generation ELISA. The highest HCV seroprevalence levels were observed in haemophiliacs (87.0%) and intravenous drug abusers (IVDA) (78.9%). The HCV-seropositivity rates of polytransfused and organ transplant recipients were nearly identical (18.4% vs. 16.8%). Significantly lower HCV-seroprevalence rates were determined in chronic haemodialysis patients (8.1%) and homo/bisexuals (10.0%). The lowest HCV seroprevalence levels were found in the groups of female prostitutes (1.4%) and health care staff (0.8%). A strong correlation between HCV seropositivity and the presence of antibodies against HIV-1, HBc and HCMV was observed. There was also an association between HCV seropositivity and HAV. The seroprevalence of HDV and the proportion of HBsAg and HBeAg carriers was not significantly influenced by HCV serostatus. The incidence of HCV infection in renal transplant recipients was 3.9%. In 10 (6.5%) patients, anti-HCV seroconversion was observed in the immediate post-transplantation period followed by a decrease of the index value and finally, disappearance of antibodies at the end of the study. Antibodies passively acquired through intravenous immunoglobulin (IVIG) donation may account for overestimation of HCV seroprevalence in retrospective seroepidemiological surveys as established by our findings.

High prevalence of hepatitis C infection among Brazilian hemodialysis patients in Rio de Janeiro: a one-year follow-up study

Nearly 400 hemodialysis patients treated at 5 different hemodialysis units in Rio de Janeiro were tested for one year for the presence of hepatitis C and B markers. During the same period, samples were also obtained from 35 continuous ambulatory peritoneal dialysis (CAPD) patients and from 242 health care workers. Depending on the hemodialysis unit studied, anti-HCV prevalence rates ranging from 47% to 82% (mean 65%) were detected. CAPD patients showed a lower prevalence of 17%. The prevalence of antibodies against hepatitis C virus (anti-HCV) among health care workers was 2.9%. We observed a hepatitis C attack rate of 11.5% per year in the anti-HCV-negative hemodialysis patient population. An average of 9.4% of the hemodialysis patients were chronic carriers of hepatitis B virus (HBV) (range 1.8% - 20.4%), while 48.9% showed markers of previous HBV infection. The HBV attack rate was 4.5% per year (range 0% - 6%). These results indicate an alarming high prevalence of anti-HCV among hemodialysis patients of this studied region.