Chapter 15 1. Thin, spiral-shaped bacteria that are surrounded by a mucoid layer 2. Axial filaments, structurally similar to bacterial flagella, confer motility on these organisms. • The pathogenic treponemes (T. pallidum, T. pertenue, and T. carateum) cannot be distinguished morphologically or serologically, but they exhibit distinctive clinical manifestations and epidemiology. A Shared treponemal properties 1. Treponemes are shorter than Borreliae and possess three axial filaments. 2. Anaerobic (or microaerophilic) organisms that cannot be grown in the laboratory • Because they are so thin, treponemes cannot be seen by light microscopy of Giemsa-stained specimens. • Organisms can be visualized by dark-field microscopy or by fluorescence microscopy of specimens stained with fluorescent-labeled antitreponemal antibody. • Nontreponemal tests (nonspecific for tissue damage) • Treponemal tests (specific for antibody to Treponema antigens)
Spirochetes
