Table 1.

Reverse Sequence Syphilis Screening Algorithm

1. Screen with a treponemal test, either an enzyme immunoassay (e.g. syphilis IgG) or a chemoluminescence assay (e.g. FTA*)

a. If treponemal test negative, syphilis is not present

b. If treponemal test positive, perform a non-treponemal test (e.g. RPR† or VDRL‡)

2. Confirmation with non-treponemal test result

a. If non-treponemal test positive, patient has syphilis

b. If non-treponemal test negative, perform a different specific test (e.g. TP-PA§)

3. Second (different) treponemal test result

a. If second treponemal test result positive, patient has syphilis

b. If second treponemal test result negative, patient does not have syphilis (may have false positive test or treated syphilis)

^*FTA = fluorescent treponemal antibody.

^†RPR = rapid plasmin reagin.

^‡VDRL = Venereal Disease Research Laboratory.

^§TP-PA = Treponemal pallidum particle agglutination.

Adapted from references 2 and 3.