Epidemiology of hepatitis C virus infection in chronic haemodialysis

There is a high prevalence of hepatitis virus infection in haemodialysis patients (17.7% of patients on the EDTA registry). That prevalence varies according to countries with a North-South gradient but also according to institutions or to the mode of treatment: haemodialysis in a unit or at home, peritoneal dialysis. Post-transfusional contamination was the number one risk factor before 1991. The incidence of infection in haemodialysis units is also variable, which reveals the risk of nosocomial transmission between patients. Strict observance of universal precautions against nosocomial infections reduces the contamination risk. The relevancy of separating patients is controversial. Other risk factors exist in haemodialysis patients, especially in those with heavier medical records, multiple surgery, endoscopy. Diagnostic anti-HCV antibody screening has improved in terms of specificity and sensitivity. HCV RNA detection by PCR confirms that most HCV antibody-positive patients are also viraemic and potentially contaminant; it permits detecting recent contamination. Virus genotyping is epidemiologically relevant because it offers the possibility to trace infections, and may also have therapeutical interest. Prevalence is greater in personnel than in the general population, which underlines the necessity to observe universal precautions.