title: De novo HCV infection among dialysis patients: a prospective study by HCV core antigen ELISA assay.
abstract: BACKGROUND
  Dialysis patients remain a high-risk group for hepatitis C virus infection. The current diagnosis of hepatitis C virus in dialysis patients includes serological measurement of anti-hepatitis C virus antibody; however, nucleic acid amplification technology for assessing hepatitis C virus viraemia is commonly used in other populations. An enzyme-linked immunosorbent assay test for detecting antibody to hepatitis C nucleocapsid core antigen (hepatitis C virus core antigen) in human serum has been recently developed (hepatitis C virus Core Antigen enzyme-linked immunosorbent assay test). It is conceived for screening of donor blood products to significantly reduce the 'serologic window' occurring before seroconversion during acute hepatitis C virus.
  
  
  OBJECTIVE
  A cohort (n = 72) of patients on maintenance haemodialysis in a single unit in the years 2000-2003 was included. Study patients were tested monthly by hepatitis C virus Core Antigen enzyme-linked immunosorbent assay in a prospective, clinical trial. Routine results obtained by hepatitis C virus Core Antigen enzyme-linked immunosorbent assay test were confirmed by assessing hepatitis C virus viraemia by branched-chain DNA (bDNA) signal amplification assay.
  
  
  RESULTS
  De novo hepatitis C virus infection was identified in three patients during the study period; the hepatitis C virus incidence was 1.38% (95% confidence intervals, 1.31-4.09) per year. In each patient, hepatitis C virus core antigen testing allowed the serological identification of acute hepatitis C virus before anti-hepatitis C virus seroconversion. Hepatitis C virus RNA testing confirmed the results obtained by hepatitis C virus Core Antigen enzyme-linked immunosorbent assay in all cases. The time from initial hepatitis C virus detection by hepatitis C virus Core Antigen Assay and anti-hepatitis C virus seroconversion was not greater than four weeks. Two (67%) of three patients with de novo hepatitis C virus acquisition were HBsAg negative; both these patients underwent an initial phase of hepatitis C virus viraemia that was associated with an increase in alanine aminotransferase activity and preceded the seroconversion to anti-hepatitis C virus antibody. Nosocomial transmission of hepatitis C virus between haemodialysis patients was implicated in at least two (67%) of these three patients.
  
  
  CONCLUSIONS
  Serological testing for hepatitis C virus core antigen can identify acute hepatitis C virus infection before anti-hepatitis C virus seroconversion. The time from initial hepatitis C virus detection by hepatitis C virus core antigen assay and anti-hepatitis C virus seroconversion was not >4 weeks. De novo acquisition of hepatitis C virus in haemodialysis was associated with a rise in alanine aminotransferase levels. Hepatitis C virus core antigen enzyme-linked immunosorbent assay test results can be obtained in routine laboratories without the need of special equipment or training. Hepatitis C virus core antigen testing among anti-hepatitis C virus negative patients on maintenance dialysis is suggested in order to early assess de novo hepatitis C virus within dialysis units.
authors.affiliation: Division of Nephrology and Dialysis, Maggiore Hospital, IRRCS, 15 Milano, Italy. fabrizi@policlinico.mi.it
authors.forename: F
authors.initials: F
authors.lastname: Fabrizi
authors.forename: A F
authors.initials: AF
authors.lastname: de Vecchi
authors.forename: G
authors.initials: G
authors.lastname: Como
authors.forename: G
authors.initials: G
authors.lastname: Lunghi
authors.forename: P
authors.initials: P
authors.lastname: Martin
mesh_terms: D000208:Acute Disease; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D006526:Hepatitis C / Q000175:diagnosis* / Q000209:etiology; D018936:Hepatitis C Antigens / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D006435:Renal Dialysis / Q000009:adverse effects*
chemical_list: D018936:Hepatitis C Antigens