Syphilis is a sexually transmitted infection caused by Treponema pallidum.

The RPR (Rapid Plasma Reagin) and VDRL (Venereal Disease Research Laboratory) tests are non-treponemal tests that detect antibodies produced in response to cellular damage caused by syphilis.

Clinical uses include:

Screening for syphilis infection.

Monitoring treatment response (antibody titers decrease after successful therapy).

Supporting diagnosis when combined with treponemal-specific tests (e.g., TPHA, FTA-ABS).

These tests are simple, inexpensive, and widely used in routine screening.

Analyte: Non-specific antibodies (reagin) produced in response to syphilis infection.

Normal Result: Non-reactive (no antibodies detected).

Positive Result: Reactive → suggests syphilis infection (requires confirmation with treponemal tests).

Clinical Use:

Detects syphilis infection.

Monitors disease activity and treatment effectiveness.

Helps in public health screening programs.