Treponema pallidum is called Treponema pallidum because it is transparent and not easily stained. Staining with Giemsa stains peach. It is a treponemal, soft and slender spirochete shaped like a metal shaving, about 6-12 μm long and 0.09-0.18 μm wide, with 8-12 neat and uniform helices.
Antibody detection of syphilis is divided into two types: non-Treponema pallidum antigen serological test and Treponema pallidum antigen serological test.
- Non-Treponema pallidum antigen serological test: mainly venereal disease research laboratory test (VDRL), unheated serum reagin test (USR), rapid plasma reagin ring card test (RPR) toluidine red unheated serum test (Trust).
- Serological test for Treponema pallidum antigen: Treponema pallidum particle agglutination assay (TPPA), Treponema pallidum hemagglutination assay (TPHA), syphilis enzyme-link immunosorbent assay (ELISA), chemiluminescent immunoassay (CLIA), such as ayphilis immunochromatography-syphilis rapid detection (RT), Treponema pallidum antibody absorption assay (FTA-ABS), Treponema pallidum Western blot (WB) are commonly used.TP15, TP17 and TP47 are outer membrance lipoproteins of Treponema pallidum