Review of the standard tests for syphilis and evaluation of a new commercial elisa, the syphilis bio‐enzabead test

Abstract

AbstractTo date, there are eight serologic tests considered Standard for the serodiagnosis of syphilis; however, the syphilis Bio‐EnzaBead test is the first commercially available enzyme‐linked immunosorbent assay (ELISA) for the confirmation of a reactive nontreponemal test result in the serodiagnosis of syphilis. The Bio‐EnzaBead has a sensitivity of 95.2% in untreated syphilis when read at 405 nm with 80% of the 1 + optical density (OD) used as the breakpoint OD between reactive and nonreactive results. This sensitivity is comparable to the sensitivity of the microhemag‐glutination assay (MHA‐TP) of 97.6% in untreated syphilis. The specificity of the syphilis Bio‐EnzaBead when read as described above is 94.7%, compared with the 99.3% of the MHA‐TP and the 98.1% of the fluorescent treponemal antibody‐absorption (FTA‐ABS) test. Heating of the specimens did not adversely affect the test outcome, and it eliminated background readings seen with the negative control beads.