Incidence and risk factors of hepatitis C virus infection in a haemodialysis unit

BACKGROUND: Hepatitis viruses have become one of the main infectiousproblems in patients on maintenance haemodialysis. The aim of this studywas to prospectively investigate the incidence of de novo hepatitis C virus(HCV) infection in a haemodialysis unit and to identify factors currentlyinvolved in HCV transmission to haemodialysis patients. METHODS: Onehundred and fourteen anti-HCV negative and HCV-RNA negative patients whostarted long-term haemodialysis were followed for a mean period of 36months (range 18- 56). Liver tests and anti-HCV were performed at 6-monthintervals. Factors that might be implicated in HCV transmission, such asblood transfusions, sexual habits, surgery and other invasive procedures,were recorded. HCV markers were re-examined in transfused blood and the HCVgenotype was investigated in seroconverters to anti-HCV and in patientswith previous HCV infection who were treated in the vicinity of those whoseroconverted. RESULTS: Eight patients (7%) seroconverted to anti-HCV andseven of them became HCV-RNA positive. HCV markers, including HCV-RNA, werenegative in the blood transfused to seroconverters. No differences betweenseroconverters and non- seroconverters. No differences found in other riskfactors not directly related to haemodialysis. The investigation of HCVgenotype suggested that HCV transmission was not restricted to patientstreated in the vicinity of previously HCV infected patients. Occasionalfailure to observe strict measures of asepsis was detected in thehaemodialysis unit and this was the only factor that might beincriminating. CONCLUSIONS: HCV acquisition in patients on haemodialysis iscurrently not related to blood transfusion, and nosocomial transmissionwithin the haemodialysis unit seems to be the main mechanism of HCVinfection. Extremely careful observation of preventive measures seemsessential to eradicate HCV transmission in haemodialysis units.