TPHA | Syphilis Detection

TPHA (T. pallidum hemagglutination) test – is a serological blood test designed for the detection of syphilis – a chronic sexually transmitted infection caused by the bacterium Treponema pallidum. TPHA is a specific test that confirms or excludes the infection, often used in conjunction with other syphilis tests (e.g., RPR, VDRL).

A positive TPHA result usually manifests 3–4 weeks after infection, when the body starts producing antibodies against T. pallidum. These antibodies often persist for life – even after successful treatment, therefore TPHA is suitable for diagnosis, but not for monitoring treatment efficacy.

Principle of the test: The test is based on the binding of antibodies against T. pallidum to antigen-coated red blood cells. The result is presented as positive or negative.

Recommendations:

• Recommended for individuals who have had risky sexual encounters or exhibit symptoms characteristic of syphilis (sores, skin rashes).
• Useful for evaluating the stage of syphilis in conjunction with other non-specific tests (RPR, VDRL).
• Administered to pregnant women, donors, individuals planning surgeries, or when assessing infertility causes.
• A positive TPHA requires additional clinical evaluation and, if necessary, initiation of treatment.
• No specific preparation is needed for the test.