Further evaluation of an automated fluorescent treponemal antibody test for syphilis.

Improvements in the equipment for the automated fluorescent treponemal antibody (AFTA) test for syphilis prompted this comparative study of the AFTA and its manual counterpart, the fluorescent treponemal antibody-absorption (FTA-ABS) test. The AFTA equipment operated satisfactorily, required only minimal monitoring, and afforded a three-to fourfold increase over the number of sera that could be tested manually by one serologist. The AFTA and FTA-ABS tests agreed well with only 2.1% of the sera yielding conflicting results. The AFTA was less precise than the FTA-ABS on sera retested because of original conflicting results and on sera retested within the same run to determine reproducibility. However, these differences were not large, and AFTA test performance was considered to be within the limits acceptable for a diagnostic serological procedure.