Syphilis is a chronic bacterial infection caused by the spirochaete Treponema pallidum. It is usually acquired by sexual contact but may also be transmitted by transfusion of infected blood.

An estimated 11.76 million cases of syphilis occurred worldwide in 1999. The incidence and prevalence of the disease varies widely in different parts of the world and may fluctuate considerably within any one region from year to year. The highest rates are seen in developing countries, particularly sub-Saharan Africa and South and Southeast Asia.

Initial infection typically produces sores, known as chancres, at the site of infection. The bacteria then move throughout the body, damaging many organs over time. The course of the disease is divided into four stages. An infected person who has not been treated may infect others during the first two stages, which usually last one to two years. In its late stages, untreated syphilis, although not contagious, can cause serious and irreversible cardiovascular and neurological problems.

Diagnosis usually depends on the demonstration of antibodies in the blood. Two types of antibody are produced in response to infection, non-specific anti-lipid reagin antibody and specific anti-treponemal antibody. These appear soon after infection; the specific anti-treponemal antibodies may persist for many years, whereas the reagin antibodies may disappear after treatment.

Test formats

RPR: a fast, reliable and robust assay for the detection of non treponemal rapid plasma reagin antibodies in human serum or plasma. The test consists of modified VDRL antigen containing microparticulate carbon, which aggregates in the presence of reagin type antibodies, indicating a positive result and can be read macroscopically. Click here to view our RPR microsite.

TPHA: a fast, reliable and robust haemagglutination assay for detection of treponemal antibodies in human serum and plasma. TPHA uses preserved avian erythrocytes coated with antigens of T. pallidum (Nichols strain), which will bind with specific antibody present in patient’s serum or plasma. High flexibility is achieved with wide range of kit sizes available including a specially configured kit for use on the Olympus PK7200 and 7300. Click here to view our TPHA microsite.