title: The risk of HCV RNA contamination in serology screening instruments with a fixed needle for sample transfer.
abstract: BACKGROUND
  Hepatitis C diagnostics involve antibody screening and confirmation of current infection by detection of HCV RNA positivity. In screening instruments with fixed pipetting needle, there is a risk of sample carry-over contamination.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the risk of such contamination in a proposed clinical setting.
  
  
  METHODS
  In the present study, known HCV RNA positive (n=149) and negative (n=149) samples were analysed by anti-HCV Abbott in an Architect instrument in an alternating fashion in order to test for contamination.
  
  
  RESULTS
  In subsequent retesting of the previously HCV RNA-negative samples, six samples (4%) were positive by the Cobas Taqman assay with a maximum level of 33 IU/mL. The results show that there is a risk for transfer of HCV in the Architect instrument but they also show that the levels of HCV RNA observed are low.
  
  
  CONCLUSIONS
  We conclude that complementary HCV RNA testing on samples identified as anti-HCV positive by screening can be recommended because the complementary results are reliable in the majority of cases when either HCV RNA is negative or HCV RNA is positive with a level >1000 IU/mL. In a minority of cases, with low HCV RNA after anti-HCV antibody screening, cross-contamination should be suspected and a new sample requested for HCV RNA testing. This strategy would reduce the need for obtaining a new sample from the vast majority of patients with a newly discovered HCV antibody positivity.
authors.affiliation: Division Clinical Microbiology, Department of Clinical and Experimental Medicine, Linköping University, Sweden. Electronic address: Elin.Rondahl@lio.se.
authors.forename: Elin
authors.initials: E
authors.lastname: Rondahl
authors.affiliation: Division Clinical Microbiology, Department of Clinical and Experimental Medicine, Linköping University, Sweden. Electronic address: Maria.Gruber@lio.se.
authors.forename: Maria
authors.initials: M
authors.lastname: Gruber
authors.affiliation: Division Clinical Microbiology, Department of Clinical and Experimental Medicine, Linköping University, Sweden. Electronic address: Sandra.Joelsson@lio.se.
authors.forename: Sandra
authors.initials: S
authors.lastname: Joelsson
authors.affiliation: Division Clinical Microbiology, Örebro University, Sweden. Electronic address: Martin.Sundqvist@orebroll.se.
authors.forename: Martin
authors.initials: M
authors.lastname: Sundqvist
authors.affiliation: Division Clinical Microbiology, Department of Clinical and Experimental Medicine, Linköping University, Sweden; Division for Infection Control and Prevention, Östergötland County, Sweden. Electronic address: Britt.Akerlind@lio.se.
authors.forename: Britt
authors.initials: B
authors.lastname: Åkerlind
authors.affiliation: Division of Infectious Diseases, Department of Clinical and Experimental Medicine, Linköping University, Sweden. Electronic address: Kristina.Cardell@lio.se.
authors.forename: Kristina
authors.initials: K
authors.lastname: Cardell
authors.affiliation: Department of Clinical Microbiology, Göteborg University, Sweden. Electronic address: magnus.lindh@microbio.gu.se.
authors.forename: Magnus
authors.initials: M
authors.lastname: Lindh
authors.affiliation: Division Clinical Microbiology, Department of Clinical and Experimental Medicine, Linköping University, Sweden; Division of Infectious Diseases, Department of Clinical and Experimental Medicine, Linköping University, Sweden. Electronic address: Lena.Serrander@lio.se.
authors.forename: Lena
authors.initials: L
authors.lastname: Serrander
mesh_terms: D019411:Clinical Laboratory Techniques / Q000295:instrumentation* / Q000379:methods*; D004866:Equipment Contamination; D016174:Hepacivirus / Q000235:genetics*; D006526:Hepatitis C / Q000175:diagnosis*; D006801:Humans; D008403:Mass Screening / Q000295:instrumentation / Q000379:methods; D012367:RNA, Viral / Q000302:isolation & purification*; D018570:Risk Assessment
chemical_list: D012367:RNA, Viral
keywords: Contamination; HCV; Screening