title: Longitudinal changes in viral RNA concentration in patients with chronic hepatitis C and/or HIV infection in the absence of antiviral therapy.
abstract: BACKGROUND
  The concentration of circulating viral RNA at baseline and during antiviral therapy predicts response in both HIV infection and chronic hepatitis C.
  
  
  METHODS
  Retrospective review of longitudinal plasma HCV-RNA determinations in untreated chronic hepatitis C patients. As comparison, longitudinal plasma HIV-RNA measurements were performed in untreated HIV individuals.
  
  
  RESULTS
  A total of 3169 HCV-RNA determinations over 43.0±31.6 months were available for 818 chronic hepatitis C patients. For 333 HIV individuals, 1998 HIV-RNA measurements were examined over 27.3±17.5 months. Overall 44% consecutive specimens had >0.5 log variation in HCV-RNA values compared to 23% for HIV-RNA (p<0.001). These rates were 15% and 4%, respectively, for variations >1 log (p<0.001). In multivariate analysis (odds ratio, 95% confidence interval, p), the likelihood of experiencing HCV-RNA variations >0.5 log IU/mL was greater in patients with lower HCV-RNA (0.35 per log[0.26-0.47], 0.001), HIV coinfection (2.57[91.56-4.23], <0.001) and IL28B-CC (1.87[1.28-2.74], 0.001).
  
  
  CONCLUSIONS
  Fluctuation in circulating HCV-RNA may be clinically meaningful in a substantial proportion of chronic hepatitis C patients. It may influence the best time to prescribe antiviral therapy. Moreover, decisions based on early viral kinetics, such as early stopping rules, may require testing of baseline specimens the closest to treatment initiation.
authors.affiliation: Department of Infectious Diseases, Hospital Carlos III, Madrid, Spain. Electronic address: pm.barreiro@gmail.es.
authors.forename: Pablo
authors.initials: P
authors.lastname: Barreiro
authors.forename: Pablo
authors.initials: P
authors.lastname: Labarga
authors.forename: José V
authors.initials: JV
authors.lastname: Fernández-Montero
authors.forename: Eva
authors.initials: E
authors.lastname: Poveda
authors.forename: Carmen
authors.initials: C
authors.lastname: de Mendoza
authors.forename: Clara
authors.initials: C
authors.lastname: Sánchez
authors.forename: Eugenia
authors.initials: E
authors.lastname: Vispo
authors.forename: Vincent
authors.initials: V
authors.lastname: Soriano
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006678:HIV / Q000302:isolation & purification*; D015658:HIV Infections / Q000150:complications / Q000821:virology*; D016174:Hepacivirus / Q000302:isolation & purification*; D019698:Hepatitis C, Chronic / Q000150:complications / Q000821:virology*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012367:RNA, Viral / Q000097:blood*; D012189:Retrospective Studies; D019562:Viral Load
chemical_list: D012367:RNA, Viral
keywords: Antiviral therapy; HCV; HIV; Hepatitis C; Viral load