마지막 업데이트: 2026년 8월 30일
Syphilis is one of the sexually transmitted infections I see regularly. How it presents depends on the stage — a painless genital ulcer early on, a rash on the palms and soles later. A blood test is the only way to confirm the diagnosis, and that is where the confusion starts, because there are two different families of blood test and each has its own strengths and limits.
This matters more than a technical detail. Patients who receive a positive result without a full explanation often leave badly frightened, and end up going from clinic to clinic looking for a second opinion that says something different. Understanding what each test actually measures usually removes the fear entirely.

1. Nontreponemal tests — the screening tests
These are used first, when syphilis is suspected. Their strength is that they reflect active infection, which also makes them the tests used to check whether treatment is working.
- VDRL (Venereal Disease Research Laboratory)
- RPR (Rapid Plasma Reagin)
Their weakness is that they can turn positive when there is no syphilis at all — a biological false positive, which several other conditions can cause. That is precisely why a positive screening test is never the end of the story. They can also read falsely negative very early in infection, before antibodies have developed, so a recent exposure with a negative result may need repeating.
2. Treponemal tests — the confirmation tests
If a VDRL or RPR comes back positive, the diagnosis has to be confirmed with a treponemal test.
- TP-PA (Treponema Pallidum Particle Agglutination)
- FTA-ABS (Fluorescent Treponemal Antibody Absorbed)
These are highly accurate for syphilis. Their limitation is the one that causes the most distress: a treponemal test stays positive for the rest of your life, even after the infection has been completely cured. It tells you that you have encountered syphilis at some point — not that you have it now. This is why treatment can never be judged by a treponemal test alone.
One practical note, because it confuses people who compare results between hospitals: some laboratories now run the two in the opposite order, using an automated treponemal test as the initial screen and then adding a VDRL or RPR afterwards. If your treponemal test came back first, that is a laboratory workflow rather than a mistake. The logic of interpreting the pair together does not change.
Reading the two together
The practical rule is simple once you have it: the confirmation test answers whether it was ever syphilis, and the screening test answers whether it is active now and whether the treatment is working. Treatment response is followed by watching the VDRL or RPR titre fall over the months after treatment. A permanently positive treponemal test alongside a falling titre is exactly what a successfully treated patient looks like.

Two practical points that follow from all this. A confirmed diagnosis means current sexual partners need testing and treatment as well, whatever your own result now shows. And because syphilis travels in company, testing for other sexually transmitted infections at the same time is standard rather than an extra.
Three things that must not be left out of the conversation
HIV testing. Syphilis and HIV travel together more closely than any other pair in this field: the ulcer of early syphilis breaks the skin barrier and raises the risk of acquiring HIV, and the two are frequently diagnosed in the same person. An HIV test belongs with a syphilis diagnosis as a matter of routine, not suspicion. HIV testing is not carried out in the urology clinic here — at Bangkok Hospital Headquarters it is handled by the Infectious Diseases department, and I refer patients there. Testing and treatment for other sexually transmitted infections, and HPV vaccination, are available with me.
임신. If you are pregnant, may be pregnant, or your partner is, this changes from a matter about you to a matter about the baby. Syphilis crosses the placenta and can cause serious harm to an unborn child, and it is one of the few such infections that is almost entirely preventable — treatment during pregnancy protects the baby. Antenatal screening exists precisely for this reason. Tell your obstetric team, and do it early, because the timing of treatment during pregnancy affects how well the baby is protected.
Symptoms in the eyes, ears or nervous system. Syphilis can affect these at any stage, not only late in the disease, and when it does the treatment is different and more intensive. Seek assessment the same day — in Thailand you can call 1669 — for any change in vision, new eye pain or redness, new hearing loss, ringing in the ears or vertigo, severe headache with neck stiffness, or new weakness, numbness or confusion. Eyesight in particular can be lost, and the window to protect it is short. Say that you have syphilis, or a positive syphilis test, when you arrive — it is the single piece of information that changes what happens next.
Syphilis is a very treatable infection — treatment is straightforward when it is done correctly. What turns it into a frightening experience is usually not the disease but the test results arriving without an explanation. If you have a positive result and nobody has walked you through what it means, ask. Once you can read your own results, the panic tends to disappear.
매독 혈액 검사 결과에 대한 우려가 있거나 성병 진단 및 치료가 필요한 경우, Soaraweel Weerasopone 박사께서 방콕 병원 본원에서 비밀 상담을 제공합니다. 진료 예약. 사미즈 시라차 병원 예약은 비뇨기과로 전화하여 하실 수 있습니다. 088-022-1445. Questions about the cost of testing or treatment should go to the hospital directly — for Bangkok Hospital, by email to bhquro@bdms.co.th.
매독 혈액 검사에 대한 자주 묻는 질문
비트레포네마 검사(VDRL, RPR)는 활동성 매독 감염을 탐지하고 치료 반응을 모니터링하기 위한 선별 검사로 사용됩니다. 트레포네마 검사(TP-PA, FTA-ABS)는 매독에 대한 특이도가 매우 높지만 성공적인 치료 후에도 평생 양성으로 남아있기 때문에 치료 결과를 평가하는 데 단독으로 사용할 수 없는 확진 검사입니다.
양성 VDRL 또는 RPR은 강력한 지표이지만 확정적인 진단은 아닙니다. 이러한 선별 검사는 자가면역 질환이나 바이러스 감염과 같은 다른 질환으로 인해 가끔 위양성을 나타낼 수 있습니다. 매독의 확정적인 진단을 위해서는 항상 확증적인 트레포네마 검사(TP-PA 또는 FTA-ABS)가 필요합니다.
매독균에 대한 특정 항체를 검출하는 매독 검사는 감염이 완전히 치료된 후에도 일단 생성되면 평생 혈류에 남아 있습니다. 이는 정상적인 소견이며 감염이 아직 활동 중임을 의미하지는 않습니다. 치료 성공 여부는 비매독 검사(VDRL 또는 RPR)를 사용하여 모니터링하며, 효과적인 치료 후에는 역가가 감소하는 것을 보여야 합니다.
치료 반응은 시간이 지남에 따라 VDRL 또는 RPR 역가를 모니터링하여 추적합니다. 성공적인 치료 후, 비트레포넬 역가는 6~12개월 이내에 4배 이상 감소해야 합니다. 역가가 안정적이거나 상승하는 것은 치료 실패 또는 재감염을 나타낼 수 있으며, 전문가의 추가 평가가 필요합니다.
No. Some laboratories now run an automated treponemal test as the initial screen and add a VDRL or RPR afterwards, which is the reverse of the traditional order. This is a laboratory workflow rather than an error, and it does not change how the two results are interpreted together: the treponemal test answers whether it was ever syphilis, and the nontreponemal titre answers whether it is active now and whether treatment is working.
Yes. Syphilis and HIV are closely linked: the ulcer of early syphilis breaks the skin barrier and raises the risk of acquiring HIV, and the two are frequently found in the same person. An HIV test belongs with a syphilis diagnosis as routine rather than as a matter of suspicion, and testing for other sexually transmitted infections at the same time is standard. HIV testing is not performed in the urology clinic; at Bangkok Hospital Headquarters it is handled by the Infectious Diseases department and patients are referred there. Testing and treatment for other sexually transmitted infections, and HPV vaccination, are available in the urology clinic.
Considerably. Syphilis crosses the placenta and can seriously harm an unborn child, and it is one of the few such infections that is almost entirely preventable, because treatment during pregnancy protects the baby. Antenatal screening exists for exactly this reason. Tell your obstetric team early, since the timing of treatment in pregnancy affects how well the baby is protected. This applies equally when it is the partner who has tested positive.
Syphilis can affect the eyes, ears and nervous system at any stage, not only late in the disease, and when it does the treatment is different and more intensive. Seek assessment the same day for any change in vision, new eye pain or redness, new hearing loss, ringing in the ears or vertigo, severe headache with neck stiffness, or new weakness, numbness or confusion. Eyesight in particular can be lost and the window to protect it is short. State that you have syphilis or a positive syphilis test on arrival, because that is the information that changes what happens next. In Thailand the emergency number is 1669.
Yes, syphilis is highly curable, especially when diagnosed and treated early. The standard treatment is penicillin G injection, with the dose and duration depending on the stage of infection. Early diagnosis, correct treatment, and regular follow-up blood tests are essential to ensure complete cure and prevent complications or transmission to partners. Current sexual partners should be tested and treated as well.
Yes, and it suits this situation particularly well, because the main task is explaining results you already hold. Bangkok Hospital Headquarters offers a Telemedicine service, arranged in advance by email to the Urology department at bhquro@bdms.co.th. Send the actual laboratory report rather than a summary, including the titre and the date, since the numbers and their trend are what the interpretation rests on. Treatment itself is given by injection and must be done in person. Samitivej Sriracha is in-person only, booked through the Urology department line 088-022-1445.
고지 사항: This content is written and reviewed by Dr. Soarawee Weerasopone, a board-certified urologist at Bangkok Hospital Headquarters. It is intended for educational purposes only and does not constitute medical advice. Blood test results must be interpreted by a doctor who knows your history — do not draw conclusions about your own results from this article alone. No medical advice, diagnosis or prescription is provided through personal messaging channels or social media. Always consult a qualified healthcare professional before starting any medical treatment. In an emergency, attend the nearest emergency department — in Thailand the emergency number is 1669.
의학적 작성 및 검토: 소아라위 웨라소폰 박사(Dr. Pom) — 방콕 병원 본점 공인 비뇨기과 전문의, 2016년부터 비뇨기과 진료 중. 수련: 대만 창 Gung 기념병원 로봇 수술(2019) · 연수: 도쿄 준텐도 대학 병원 내비뇨기과(2022) · 연구원 및 임상 참관인, 미국 베이로 의과대학 스콧 비뇨기과(2025–2026).

Soarawee Weerasopone 의사(Dr. Pom)는 Bangkok Hospital Headquarters의 인증(Board-certified) 비뇨의학과 전문의로, 남성 건강, 로봇수술(da Vinci Xi), 신장결석 치료를 전문으로 합니다. 현재 Baylor College of Medicine의 Scott Department of Urology에서 Mohit Khera 교수의 지도하에 연구 학자(Research Scholar) 및 임상 참관의(Clinical Observer)로 재직 중입니다(2025–2026). 대만 Chang Gung Memorial Hospital에서 로봇수술 펠로우십(2019)을, 도쿄 Juntendo University Hospital에서 내비뇨기(endourology) 참관(2022)을 이수했습니다.


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