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Published on: March 13, 2015
[Possibilities and limits of anti-HCV antibody screening in the blood donation service]
B Fölsch1, C Gabriel, M M Wilders-Truschnig
1Department für Transfusionsmedizin und Immunhämatologie, Chirurgische Universitäts-klinik, Graz.
Background:
Hepatitis C virus (HCV) is responsible for the majority of post-transfusion hepatitis cases. We compared the correlation and reproducibility of different screening and confirmatory tests.
Material And Methods:
1,406 samples of voluntary blood donors were tested in parallel using 3 enzyme-linked immuno sorbent assays (ELISA) for HCV antibodies. Those samples that were positive in at least 1 of the 3 tests were additionally tested in a 3rd-generation ELISA as well as in 3 different confirmatory tests.
Results:
13 samples (0.92%) were repeat reactive in at least 1 of the ELISAs with different results in the confirmatory tests. Only 3 samples (0.21%) with high sample/cutoff ratios in the ELISAs were positive in all 3 confirmatory tests.
Conclusions:
The reproducibility of the tested ELISAs and the correlation with confirmatory tests were good only in samples with a high signal to cutoff ratio. Two different high-positive ELISA results can be regarded as confirmation.

