Evaluation of a Quantitative Automated Micro-hemagglutination Assay for Antibodies to Treponema pallidum

Abstract

In a survey of approximately 700 sera from clinically-defined donors, a quantitative automated microhemagglutination assay for antibodies to Treponema pallidum (AMHA-TP) was found to be reactive with 96.4% of sera from syphilitics and with 0.9% of sera from presumed nonsyphilitics. A decrease in AMHA-TP titer seemed to be associated with treatment of syphilis at the primary or secondary stage, but some degree of AMHA-TP reactivity could still be found one or more years after presumably adequate treatment had been given at any stage. Including absorption of sera before testing, about 200 specimens could be quantitatively tested in a working day.