[Demonstration of hepatitis-B(surface) antigen with the Hepatest: a new passive haemagglutination test (author's transl)].

The Hepatest, a passive haemagglutination test, proved to be, like other tests of this group, significantly more sensitive for routine examination of hepatitis B(surface) antigen than tests of the first and second generation, but was not as sensitive as the Ausria II 125 test. The lowest HBs antigen concentration demonstrable in the Hepatest was 31 ng/ml for the subtype ad and 47 ng/ml for subtype ay (in the Ausria II 125 test lowest concentrations were 1.0 and 1.5 ng/ml, respectively). There were several false-positive reactions in the specificity test. Thus all positive reactions would need to be checked, more often than with the Ausria test. But the Hepatest proved to be the most practicable of all the third generation tests, both with regard to shortness of reaction time, technical requirements and ease of reading off the results.