title: Spontaneous viral clearance following acute hepatitis C infection: a systematic review of longitudinal studies.
abstract: A large number of studies have reported on spontaneous viral clearance rates in acute hepatitis C infection, however most have been small, and reported rates have varied quite widely. To improve the precision of the estimated rate of spontaneous viral clearance, a systematic review was conducted of longitudinal studies. Factors associated with viral clearance were also examined. Inclusion criteria for studies were: longitudinal assessment from time of acute hepatitis C; hepatitis C virus RNA analysis as determinant of viral clearance; untreated for acute hepatitis C. Information on study population, and factors that may influence viral clearance were extracted from each study. Viral clearance was defined among individuals with at least 6 months follow-up following acute hepatitis C. The number of subjects with viral clearance was expressed as a proportion for each study and a weighted mean for proportion was calculated. A total of 31 studies were examined. Study populations included nine studies of post-transfusion hepatitis, 19 of acute clinical hepatitis, and three of sero-incident cases. In total, data was available for 675 subjects and the mean study population was 22 (range 4-67). The proportion with viral clearance ranged from 0.0 to 0.8, with a weighted mean of 0.26 (95% CI 0.22-0.29). Factors associated with viral clearance were female gender and acute clinical hepatitis C study population. Further studies are required to more clearly define predictors of clearance and guide therapeutic intervention strategies.
authors.affiliation: National Centre in HIV Epidemiology and Clinical Research, The University of New South Wales, Darlinghurst, Sydney, NSW, Australia.
authors.forename: J M
authors.initials: JM
authors.lastname: Micallef
authors.forename: J M
authors.initials: JM
authors.lastname: Kaldor
authors.forename: G J
authors.initials: GJ
authors.lastname: Dore
mesh_terms: D000328:Adult; D005260:Female; D016174:Hepacivirus / Q000254:growth & development*; D006526:Hepatitis C / Q000821:virology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019562:Viral Load