Inflammation . Patient guide
Syphilis Antibodies Blood Test
Also known as: Treponema pallidum antibodies, Syphilis serology, TPHA / TPPA
What is Syphilis Antibodies
Syphilis is a sexually-transmitted bacterial infection caused by Treponema pallidum. A blood test for treponemal antibodies is the standard UK first-line screen and is part of a complete sexual health work-up alongside HIV and hepatitis B and C.
This biomarker entry is being clinically reviewed by our team. The factual content draws on UK guidance (NICE, NHS, Royal Colleges and the relevant speciality society where cited).
Reference range
Reported in antibody titre (qualitative or numerical). Final reports always carry the issuing laboratory's range, which is what your clinician will interpret against.
| Group | Range | Note |
|---|---|---|
| Negative (treponemal antibody) | No antibodies detected | No exposure or pre-treatment window (up to 3 months after exposure) |
| Positive (treponemal antibody) | Antibodies detected | Current or past syphilis; further testing required to distinguish |
| RPR / VDRL titre | reported as a dilution, e.g. 1:4, 1:8, 1:16 | Interpreted in clinical context per BASHH 2024; titres fall by at least fourfold with successful treatment |
What it is
Syphilis is divided into primary (painless genital ulcer typically 3 weeks after exposure, range 9 to 90 days), secondary (rash, fevers, lymph node swelling 4 to 10 weeks after, sometimes up to 6 months), latent (no symptoms, only detectable on blood test), and tertiary (cardiovascular and neurological complications years to decades later). The treponemal antibody test (TPHA, TPPA, or treponemal EIA) detects exposure at any stage and remains positive for life after infection. A second non-treponemal test (RPR or VDRL) is added when antibodies are positive to estimate whether the infection is active or treated.
Why a clinician would order it
Syphilis serology is requested as part of comprehensive sexual health screening, after a potential exposure, in any new long-term partnership for peace of mind, before pregnancy planning (untreated syphilis crosses the placenta), in patients presenting with the characteristic painless ulcer or rash, and increasingly as part of pre-employment or insurance health checks because syphilis rates in the UK have risen significantly since 2010.
If your level is outside the range
Symptoms of low Syphilis Antibodies
- No symptoms attributable to negative serology
What low can indicate. No current or past syphilis infection. Note that the treponemal antibody can be negative in the first 3 weeks after exposure (the window period), so a repeat test at 3 months is recommended after a known recent exposure.
Symptoms of high Syphilis Antibodies
- Symptoms depend on stage: painless genital ulcer in primary syphilis; rash on palms and soles + fevers + lymphadenopathy in secondary; nothing visible in latent syphilis; cardiovascular and neurological complications in tertiary (years to decades later)
What high can indicate. Current untreated syphilis (will need treatment), previously treated syphilis (treponemal antibody stays positive for life, the RPR / VDRL titre helps distinguish), or rarely a biological false positive in autoimmune disease, pregnancy, or some viral infections. A positive result is always followed up with confirmatory testing and treatment if active.
Testing tips
No fasting required. Time the test at least 3 weeks (ideally 3 months) after any known potential exposure to clear the antibody window period. Confidential testing is the standard at private clinics, with results explained by a GMC-registered doctor and a written report you can share with any other clinician you choose to.
Where you can get this tested
Syphilis Antibodies is included in the following WMG Health panels. Same-day appointments at our Harley Street clinic, with results clinician-reviewed.
Want a specific combination of markers we do not have a panel for? Build a custom panel and our clinicians will design one for you.
Symptoms often investigated with Syphilis Antibodies
Syphilis Antibodies is commonly tested when patients present with the following symptoms. If any of these resonate with you, the linked guides explain what to look for and which test pathway is appropriate.
Sources
UK guidance our clinicians use when interpreting this marker.
- BASHH UK guidelines for the management of syphilis 2024
- UK Health Security Agency: Syphilis surveillance
This page is general patient information, not personal medical advice. A GMC-registered clinician will review your results and tailor any interpretation to you. See our Editorial Policy for how we write and review content.
Common questions about Syphilis Antibodies
What is a normal Syphilis Antibodies range?
Negative (treponemal antibody): No antibodies detected (No exposure or pre-treatment window (up to 3 months after exposure)). Positive (treponemal antibody): Antibodies detected (Current or past syphilis; further testing required to distinguish). RPR / VDRL titre: reported as a dilution, e.g. 1:4, 1:8, 1:16 (Interpreted in clinical context per BASHH 2024; titres fall by at least fourfold with successful treatment). Always interpret your own results against the laboratory range printed on your report, since assay-specific reference ranges vary.
What does a low Syphilis Antibodies result mean?
No current or past syphilis infection. Note that the treponemal antibody can be negative in the first 3 weeks after exposure (the window period), so a repeat test at 3 months is recommended after a known recent exposure.
What does a high Syphilis Antibodies result mean?
Current untreated syphilis (will need treatment), previously treated syphilis (treponemal antibody stays positive for life, the RPR / VDRL titre helps distinguish), or rarely a biological false positive in autoimmune disease, pregnancy, or some viral infections. A positive result is always followed up with confirmatory testing and treatment if active.
Do I need to fast or prepare for the Syphilis Antibodies blood test?
No fasting required. Time the test at least 3 weeks (ideally 3 months) after any known potential exposure to clear the antibody window period. Confidential testing is the standard at private clinics, with results explained by a GMC-registered doctor and a written report you can share with any other clinician you choose to.
Can I order a Syphilis Antibodies blood test privately in London?
Yes. WMG Health offers Syphilis Antibodies as part of bespoke panels and several pre-built panels at our 134 Harley Street clinic. Results are clinician-reviewed by a GMC-registered doctor within 4 hours for the most common assays. All panels are custom-built around your specific question; bookings via /contact/ or 020 3239 3378.