The microhemagglutination assay for Treponema pallidum antibodies (MHA-TP), a new treponemal test for syphilis: where does it fit?

The status of a new treponemal test, the Microhemagglutination Assay for Treponema pallidum Antibodies (MHA-TP) is reviewed and compared with regard to its sensitivity, specificity, and current clinical application to the VDRL slide test, the most widely used non-treponemal test, and to the manual FTA-ABS test, the standard treponemal test. At present, the MHA-TP test seems to combine the simplicity and lower cost of nontreponemal tests and the sensitivity and specificity of treponemal tests, and thus enjoys features of both a screening and verification procedure. However, additional clinical experience with the test is needed before its role in the serologic diagnosis of syphilis can be conclusively determined.