It is known that syphilis is a sexual transmitted disease which pose a big threaten to
human health. Disease incidence is growing in recent years. The pathogens of syphilis
belong to pale subspecies of treponema pallidum. Human beings are the only source of
infection of syphilis and it is divided into two kinds of disease including congenital
syphilis and acquired syphilis.
The congenital syphilis is transmitted by placenta where babies are infected with treponema
pallidum. It may leads to abortion in early stage and even the alive babies may have
congenital syphilis. However, acquired syphilis is mainly transmitted by sex, kiss,
operation, blood transfusion and lactation.
Acquired syphilis is divided into three phases in clinicals : primary syphilis , secondary
syphilis and tertiary syphilis. After the infection of treponema pallidum, human body can
produce specific anti- treponema pallidum antibodies and non-specific anti-cardiolipin
antibodies. Specific anti- treponema pallidum antibodies contain IgG antibody which lasts
long and IgM antibody which lasts short in human body. IgM antibody even can last for a
lifetime but the concentration of these antibodies is low and they fail to prevent
reinfection. Non-specific anti-cardiolipin antibodies are also called reagin which is made
of lipid -like substance released by damaged tissues,lipid produced by treponema pallidum ,IgM antibody and IgG antibody stimulated by lipoprotein.
The antibody can be tested in the serum of patients with various chronic diseases and acute
illness instead of treponema pallidum. Specific anti- treponema pallidum antibodies are
produced earlier than non-specific anti-cardiolipin antibodies. Even after the treatment of
syphilis, anti- treponema pallidum antibodies can still exist and even exist for a lifetime. So early diagnosis plays a vital role in controlling and treating syphilis. There is no doubt that the lab methods with high sensitivity and specificity will do a favor to diagnosis of syphilis.
The main methods to test syphilis are rapid plasma reagin circle card test,RPR ,toluidine
red unheated—serum test,TRUST, treponema pallidum hemagglutination assay,TPHA and enzyme linked immunosorbent assay, Syphilis ELISA.