title: Incidence and patterns of hepatitis C virus seroconversion in a cohort of hemodialysis patients.
abstract: BACKGROUND
  The aim of this multicenter hemodialysis (HD) cohort study is to prospectively investigate the incidence of hepatitis C virus (HCV) infection in Greece from 1993 to 1995 and delineate early virological and serological events associated with HCV seroconversion in the HD setting.
  
  
  METHODS
  Sequential serum samples collected weekly from 562 patients were tested biochemically and serologically by means of a second- (EIA-2) and third-generation enzyme immunoassay (EIA-3). All patients with positive antibody to HCV test results (anti-HCV + ) and sequential samples from seroconverting patients were tested for HCV RNA.
  
  
  RESULTS
  Anti-HCV prevalence at study entry was 29% (163 of 562 patients), and viremia was detectable in 110 of 163 anti-HCV + patients (67.5%). HCV incidence was 6.2 cases/100 person-years. Seroconversions could not be attributed to transfusions after study entry (only 1 patient had been administered transfusion), and HD unit was associated with increased hazard for seroconversion ( P = 0.002), even after adjusting for potential differences among their patients. According to Kaplan-Meier estimation, the median interval by which the HCV RNA assay detected HCV infection earlier than anti-HCV testing was 246 and 154 days for EIA-2 and EIA-3, respectively. Detectable HCV RNA and at least 2 consecutive abnormal alanine aminotransferase levels in the preseroconversion period were observed in 29 of 30 (97%) and 14 of 32 patients (44%), respectively. Reductions in HCV RNA levels immediately after seroconversion were transient or did not occur.
  
  
  CONCLUSIONS
  On the grounds of apparent nosocomial transmission, the wide window period of HCV infection in HD patients emphasizes the need for strict adherence to specific infection-control measures in this setting.
authors.affiliation: Athens University Medical School, Athens, Greece.
authors.forename: Vana
authors.initials: V
authors.lastname: Sypsa
authors.forename: Mina
authors.initials: M
authors.lastname: Psichogiou
authors.forename: Antigoni
authors.initials: A
authors.lastname: Katsoulidou
authors.forename: Gregory
authors.initials: G
authors.lastname: Skoutelis
authors.forename: Spiridon
authors.initials: S
authors.lastname: Moutafis
authors.forename: Valsamakis
authors.initials: V
authors.lastname: Hadjiconstantinou
authors.forename: John
authors.initials: J
authors.lastname: Kakavas
authors.forename: Viktoria
authors.initials: V
authors.lastname: Kalapothaki
authors.forename: John
authors.initials: J
authors.lastname: Boletis
authors.forename: Angelos
authors.initials: A
authors.lastname: Hatzakis
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D005838:Genotype; D016174:Hepacivirus / Q000201:enzymology / Q000235:genetics / Q000276:immunology*; D006526:Hepatitis C / Q000453:epidemiology*; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods / Q000706:statistics & numerical data; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012367:RNA, Viral / Q000097:blood / Q000276:immunology; D006435:Renal Dialysis / Q000009:adverse effects*; D051437:Renal Insufficiency / Q000097:blood / Q000209:etiology / Q000821:virology; D012307:Risk Factors; D016036:Seroepidemiologic Studies
chemical_list: D000914:Antibodies, Viral; D012367:RNA, Viral; D000410:Alanine Transaminase