Evidence that use of a second‐generation hepatitis C antibody assay prevents additional cases of transfusion‐transmitted hepatitis

Abstract

The aim of this study was to determine if using hepatitis C antibody (anti-HCV) enzyme immunoassay version 2.0 (EIA2) in addition to version 1.0 (EIA1) increased the safety of the blood supply. Blood non-reactive by anti-HCV EIA1 was transfused in 1990-92. Stored samples from 40098 units, donated prior to 13 March 1992 were later tested by EIA2. For donor units reactive for anti-HCV by EIA2, a recombinant immunoblot assay (RIBA2) was also carried out. In 63 cases, recipients of transfusions which were EIA2 negative or EIA2 reactive were tested for anti-HCV and elevated alanine aminotransferase (ALT) levels 9-12 months after transfusion; pretransfusion anti-HCV status of recipients was unknown. Among these multitransfused patients receiving units that were negative by both EIA1 and EIA2, 1/26 (4%) had anti-HCV. Among transfusion recipients of units negative by EIA1, but who received at least one unit reactive by EIA2, 4/37 recipients (11%) were anti-HCV reactive (P = 0.59). For the recipients of EIA2 reactive blood, when the donor unit was RIBA2 non-reactive, 0/23 recipients were reactive by anti-HCV. Among the recipients of a RIBA2 indeterminate unit, 1/10 recipients had anti-HCV, but for patients who received at least one RIBA2 reactive unit, 3/4 recipients had anti-HCV (P = 0.03). Hence, second-generation anti-HCV testing detected additional units capable of transmitting hepatitis C that were not detected by first-generation testing. However, RIBA2 is a more specific method than EIA2 for determining units capable of transmitting HCV.

Hepatitis C Lookback Programme: a single hospital experience

“…Patients with liver disease and indeterminate results in second-generation RIBA may have HCV, viral RNA being detected in the serum of 57% of patients with non-A non-B hepatitis (Chemello et al, 1993). Third-generation assays are less likely than second-generation ELISAs and RIBAs to miss infective donors (Bukh et al, 1993;Aoki et al, 1994;Barrera et al, 1995;Vrielink et al, 1995b). Transmission of HCV has been reported by components which have tested anti-HCV negative by ELISA and RIBA but have retrospectively been shown to have been PCR positive (Kitchen et al, 1996;Bukh et al, 1993;Aoki et al, 1994;Barrera et al, 1995;Vrielink et al, 1995b), suggesting that the donor was in the window period of HCV infection.…”

“…Third-generation assays are less likely than second-generation ELISAs and RIBAs to miss infective donors (Bukh et al, 1993;Aoki et al, 1994;Barrera et al, 1995;Vrielink et al, 1995b). Transmission of HCV has been reported by components which have tested anti-HCV negative by ELISA and RIBA but have retrospectively been shown to have been PCR positive (Kitchen et al, 1996;Bukh et al, 1993;Aoki et al, 1994;Barrera et al, 1995;Vrielink et al, 1995b), suggesting that the donor was in the window period of HCV infection. However, the HCV-indeterminate donors in the current study were not in the window period as they were anti-HCV-positive by EIA and had strong reactions at either c22 or c33 on RIBA which were consistent over at least 6 months.…”