Syphilis is a sexually transmitted infection caused by Treponema pallidum.

The TPHA test is a treponemal antibody test that detects antibodies specific to the syphilis-causing bacterium.

Clinical uses include:

Confirming syphilis infection after a positive non-treponemal test (e.g., RPR, VDRL).

Differentiating true infection from false positives in screening tests.

Supporting diagnosis in patients with suspected syphilis.

The test is performed using a blood sample.

Analyte: Treponema pallidum–specific antibodies in blood serum.

Normal Result: Negative (no antibodies detected).

Positive Result: Presence of antibodies → confirms syphilis infection (past or present).

Clinical Use:

Confirms syphilis diagnosis.

Differentiates true infection from false positives in non-treponemal tests.

Guides treatment and monitoring of syphilis.