Prospects for improved laboratory diagnoses of treponemal infections and species differentiation.

The serologic diagnosis of treponemal infections has depended in the past on a variety of tests in which specificity was defined on an epidemiologic rather than on an immunologic basis. The lipoidal antigen tests possess no immunologic specificity. Tests based on whole treponemal antigens, although they do have some immunologic specificity, react with antibodies other then those generated in the course of syphilis and yaws infections. Recent developments in biotechnology now permit the identification of immunologically specific antigens in Treponema pallidum, and cloning of appropriate genetic information in Escherichia coli has led to the production of pure specific reagents. These developments will finally place the serologic diagnosis of treponemal infections on a sound immunologic basis.