Reiter haemagglutination test: a screening test for syphilis.

Using an ultrasonicate of the Reiter treponeme as antigen the Reiter haemagglutination test (RHA) was evaluated as a serological test for syphilis. Comparison of the results of the cardiolipin Wassermann reaction, Reiter protein complement-fixation test, the fluorescent treponemal antibody-absorbed (FTA-ABS) test, the Treponema pallidum haemagglutination test (TPHA) (at dilutions of 1/16 and 1/80), and the Venereal Disease Research Laboratory test with those of the RHA showed that the RHA was sensitive (85.8%) and agreed well (85.8%) with the FTA-ABS test result. Simplicity, sensitivity, availability of the antigen, and the very low cost of this test support its use as a first-line screening test for syphilis.