title: Hepatitis C viral clearance in an intravenous drug-using cohort in the Dublin area.
abstract: BACKGROUND
  The rate of spontaneous HCV viral clearance is reported as 20-25% but recent data indicate a higher frequency in some cohorts. The rate of spontaneous clearance in intravenous drug users has not been reported in an Irish setting.
  
  
  OBJECTIVE
  To determine the rate of spontaneous hepatitis C viral clearance and genotype in an Irish intravenous drug-using cohort.
  
  
  METHODS
  Drug users attending five drug treatment clinics in the Dublin were investigated. Data were prospectively recorded from January 1997 to June 2001 and follow-up testing completed in 2003. There were 496 HCV antibody positive patients identified and assessed for HCV RNA clearance. All were HIV and hepatitis B negative, 68.8% were male.
  
  
  RESULTS
  HCV RNA negativity (viral clearance) was documented in 38% of patients. Viral clearance was 47.4% in females and 34.5% in males (p = 000.6). Clearance was independent of age or duration of intravenous drug use. Viral clearance as defined as two negative consecutive HCV RNA tests, a minimum of one year apart, was sustained in 82.2% at two-year follow-up, giving an overall viral clearance of 31.1%. HCV genotype 1 and 3 were most commonly identified at 48.8% and 48.5% respectively in those with chronic infection.
  
  
  CONCLUSIONS
  Spontaneous HCV viral clearance occurs at a higher frequency than previously reported. Genotype 1 and 3 are commonest in the patient cohort.
authors.affiliation: The Drug Treatment Centre Board, Trinity Court, Pearse Street, Dublin.
authors.forename: S
authors.initials: S
authors.lastname: Keating
authors.forename: S
authors.initials: S
authors.lastname: Coughlan
authors.forename: J
authors.initials: J
authors.lastname: Connell
authors.forename: B
authors.initials: B
authors.lastname: Sweeney
authors.forename: E
authors.initials: E
authors.lastname: Keenan
mesh_terms: D000328:Adult; D017848:Blood-Borne Pathogens; D015331:Cohort Studies; D005260:Female; D005838:Genotype; D016174:Hepacivirus / Q000235:genetics / Q000276:immunology*; D006526:Hepatitis C / Q000097:blood* / Q000453:epidemiology / Q000276:immunology; D018937:Hepatitis C Antibodies / Q000097:blood*; D006801:Humans; D007494:Ireland; D008297:Male; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000097:blood* / Q000235:genetics; D016036:Seroepidemiologic Studies; D016320:Substance Abuse Treatment Centers; D015819:Substance Abuse, Intravenous / Q000821:virology*; D019562:Viral Load
chemical_list: D018937:Hepatitis C Antibodies; D012367:RNA, Viral