An algorithm for confirming screen reactivity in blood donors in enzyme immunoassays for antibodies to hepatitis C virus

Hepatitis C-related chronic liver disease among asymptomatic blood donors in the north west of England

In the first 19 months of screening, the North Western Regional Transfusion Centre (RTC) tested 224,000 consecutive blood donors for antibody to hepatitis C virus (anti-HCV) by second generation enzyme immunoassay (EIA). Of these, 366 repeatedly reactive samples were referred for confirmatory testing at Manchester Public Health Laboratory (PHL). There, the initial EIA was repeated, together with two further EIAs. All the referred samples were subjected to a confirmatory line immunoblot (RIBA-II). Reverse transcription followed by the polymerase chain reaction (RT-PCR), in order to detect viral RNA, was performed on selected samples. Among the donors, 61 accepted offers for medical review and were assessed for risk factors, clinical findings and results of standard liver function tests. Of these donors, 53 proceeded to liver biopsy. The overall prevalence of confirmed positive donors was 0.04%. Main risk factors identified included intravenous drug abuse in 31 (51%) donors and prior blood transfusion in 12 (20%) but a risk factor was not apparent in 11 (18%). Viraemia, detected by RT-PCR, could be predicted with a high degree of accuracy by means of the readily available and simpler screening and confirmatory tests (EIA and RIBA-II). Established chronic hepatitis was demonstrated in 90% of the liver biopsies. A trend towards worsening histological findings accompanied increasing concentrations of serum transaminase. Even so, many donors with normal transaminase values had abnormal biopsies including those showing chronic active hepatitis (CAH). These findings indicate that a substantial proportion of previously unrecognised asymptomatic persons with established chronic liver disease exists among North Western blood donors.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatitis C virus (HCV)-specific in vitro antibody secretion by peripheral blood lymphocytes: correlation with progression of disease and HCV RNA in HCV antibody-positive patients

Hepatitis C virus-specific in vitro antibody production (HCV IVAP) by peripheral blood lymphocytes in 53 HCV antibody-positive patients was investigated in comparison with alanine aminotransferase (ALT) levels and HCV RNA in serum samples. All 29 HCV IVAP-positive patients were HCV RNA positive; 26 had elevated ALT levels. Among the 24 HCV IVAP-negative patients, 16 were HCV RNA negative, with 12 presenting normal ALT values. These data indicate that HCV IVAP results are highly correlated (P < 0.001) with HCV RNA results and ALT levels. Our study indicates that HCV IVAP can be used as a novel assay in the diagnosis and pathogenesis exploration of HCV infection.