title: Improving the safety of blood transfusion by using a combination of two screening assays for hepatitis C virus.
abstract: OBJECTIVE
  To illustrate that the combination of a single nucleic acid amplification test (NAT) with a single immunoassay for hepatitis C virus (HCV) detection, as proposed internationally, may lead to the omission of anti-HCV reactive sera with non-reactive NAT results.
  
  
  METHODS
  In total, 822 of 519, 299 serum samples from 11 blood centres in China were retested for anti-HCV by using 10 screening assays to detect HCV antibodies. A recombinant immunoblot assay (RIBA HCV 3·0; Ortho-Clinical Diagnostics) was performed to define confirmed HCV infection status. Samples with positive or indeterminate RIBA-HCV results were tested by quantitative tests for HCV RNA (Roche Diagnostics).
  
  
  RESULTS
  We found that 47 of the 822 (5·72%) serum samples were RIBA-positive without detectable HCV RNA. For these samples, the 10 anti-HCV immunoassays gave discordant and unsatisfactory results (detection rate ranging from 10·64 to 34·04%; ratio per 100 000 donations ranging from 5·97 to 8·09). Compared with a single anti-HCV screening assay, the two-assay combination increased the detection of these samples. The five best combinations [Sorin and Lizhu enzyme immunoassays (EIAs), Ortho and Lizhu EIAs, Sorin and Wantai EIAs, Sorin EIA and Roche CIA and Ortho and Wantai EIAs] increased the detection rate from 46·81 to 55·57%, thus reducing the ratio per 100 000 donations of HCV-seropositive samples.
  
  
  CONCLUSIONS
  The combination of two anti-HCV screening immunoassays in parallel with an HCV NAT is a better strategy for HCV detection in blood centres to improve the safety of blood transfusion.
authors.affiliation: National Center for Clinical Laboratories, Beijing Hospital, Beijing, People's Republic of China.
authors.forename: K
authors.initials: K
authors.lastname: Zhang
authors.forename: L
authors.initials: L
authors.lastname: Wang
authors.forename: Y
authors.initials: Y
authors.lastname: Sun
authors.forename: R
authors.initials: R
authors.lastname: Zhang
authors.forename: G
authors.initials: G
authors.lastname: Lin
authors.forename: J
authors.initials: J
authors.lastname: Xie
authors.forename: J
authors.initials: J
authors.lastname: Li
mesh_terms: D058731:Blood Safety / Q000379:methods*; D001803:Blood Transfusion; D046148:Donor Selection / Q000379:methods*; D005260:Female; D016174:Hepacivirus; D006526:Hepatitis C / Q000097:blood*; D006801:Humans; D007118:Immunoassay / Q000379:methods; D008297:Male; D021141:Nucleic Acid Amplification Techniques / Q000379:methods; D012680:Sensitivity and Specificity
keywords: NAT; anti-HCV; blood donors; combination of two assays; detection rate