What is the VDRL test?

The VDRL (Venereal Disease Research Laboratory) test is a widely used blood screening test for syphilis. It is accessible at most laboratories worldwide, even without a doctor's referral, making it one of the most common STD screening tools available.

What does a VDRL false positive mean?

A VDRL false positive, also called a Biological False Positive (BFP) reaction, occurs when the test returns a positive result in a person who does not actually have syphilis. This affects approximately 1–2% of people tested and is typically seen at low dilution levels of less than 1:8.

What are the causes of a VDRL false positive test?

Common causes of a VDRL false positive include laboratory error or poorly trained technicians, autoimmune diseases such as SLE (Systemic Lupus Erythematosus) and Rheumatoid arthritis, febrile illnesses such as malaria, tuberculosis, and filariasis, pregnancy, recent vaccination, aging, drug addiction, liver disease, and malignancy.

Can pregnancy cause a false positive VDRL test?

Yes. Pregnancy is one of the recognized causes of a biological false positive VDRL result. Pregnant women who test positive on VDRL screening should undergo further confirmatory testing to rule out true syphilis infection.

Can a recent vaccination cause a false positive VDRL?

Yes. Recent immunization with any type of vaccine is an important cause of false positive VDRL results and should always be mentioned in the medical history when evaluating an unexpected positive syphilis test.

What should I do if my VDRL test is positive but I don't have syphilis symptoms?

If a biological false positive is suspected, a thorough medical history and further confirmatory investigations are needed to identify the true cause. It is recommended to repeat the VDRL test at 10 weeks, as most false positive results will become non-reactive by that time. Always consult a physician for proper evaluation.

VDRL False Positive Test: Causes and What to Do

마지막 업데이트: 2026년 5월 18일

소아라위 위라소폰, 비뇨기과 전문의

방콕 병원 본부, 방콕

사미티벳 스리라차 병원, 촌부리

라인 문의

VDRL test or Venereal Disease Research Laboratory test is a very common syphilis screening test. The problem will be occurred when VDRL turn positive without any suspicious of syphilis infection, we called this incident “생물학적 위양성” or BFP reaction. Today we will discuss on this BFP phenomenon.

이 문제를 경험하는 환자는 정신적, 일상적 수행에 영향을 미칩니다.

BFP phenomenon has been reported around 1-2% of an incidence. BFP usually showing out in a low dilutions (<1:8). Here are the possibilities of BFP phenomenon.

Causes of VDRL False positive phenomenon

Laboratory error from unwell-trained technicians
Autoimmune diseases – SLE or Rheumatoid arthritis
Febrile illness – Malaria, Tuberculosis, Filariasis
임신
최근 예방접종
노화
마약 중독
간 질환
강한 악의

VDRL false positive test sometimes can be detected in Pregnancy.

Once BFP phenomenon is suspected, a careful history taking and proper investigation must be done. It would be recommended to retest VDRL again at 10 weeks — most cases will turn nonreactive at that time. Any questions, you can discuss with your trusted physicians, or it would be my honor if you can text me. Take care!

내 공식 홈페이지를 방문할 수 있습니다 여기.

자주 묻는 질문 (FAQ)

Q1: What does a VDRL false positive result mean?

A VDRL false positive result means the test shows a reactive result without the person actually having a syphilis infection. This is known as a Biological False Positive (BFP) reaction, which occurs in approximately 1-2% of cases. BFP results typically appear at low dilution levels (less than 1:8) and require further investigation to identify the true underlying cause.

Q2: What conditions can cause a VDRL false positive?

Common causes of VDRL false positive include autoimmune diseases such as SLE and rheumatoid arthritis, febrile illnesses such as malaria and tuberculosis, pregnancy, recent vaccinations, aging, drug addiction, liver disease, and malignancy. Laboratory error from untrained technicians is also an important consideration when a false positive is suspected.

Q3: How can I confirm whether my VDRL positive is a true or false positive?

When a false positive is suspected, a confirmatory treponemal test such as TPHA or FTA-ABS should be performed. If the confirmatory test is negative while VDRL is positive, a BFP reaction is highly likely. Retesting VDRL at 10 weeks is also recommended, as most BFP cases will revert to non-reactive within this timeframe.

Q4: Should I be worried if my VDRL test comes back positive?

A positive VDRL result should not cause immediate panic, as false positives do occur. However, it should always be evaluated by a physician rather than ignored. A thorough clinical history, physical examination, and confirmatory testing are necessary to determine whether the result represents true syphilis infection or a biological false positive.

Q5: Can pregnancy cause a false positive VDRL?

Yes. Pregnancy is one of the recognized causes of a VDRL biological false positive reaction. Pregnant women who receive a positive VDRL result should be evaluated with a confirmatory treponemal test to differentiate a true syphilis infection from a pregnancy-related false positive, as appropriate treatment during pregnancy is critical for fetal health.

If you have received a positive VDRL result and are unsure how to interpret it, Dr. Soarawee Weerasopone offers specialist consultations in sexual health at Bangkok Hospital Headquarters. 진료 예약.

면책 조항: 본 내용은 방콕 병원 본사의 전문의인 Soarawee Weerasopone 박사가 작성하고 검토한 것입니다. 교육 목적으로만 제공되며 의학적 조언을 구성하지 않습니다. 모든 의학적 치료를 시작하기 전에 항상 자격을 갖춘 의료 전문가와 상담하십시오.

의학적으로 작성 및 검토됨: 소아라위 위라소폰 박사(폼 박사) — 방콕 병원 본원 비뇨의학과 전문의. 국제 펠로우: 베일러 의과대학(미국) · 준텐도 대학(일본) · 창궁 기념 병원(대만).

소아라위 위라소폰 박사

소라위 위라소폰 박사 (폼 박사)는 방콕 병원 본원의 비뇨의학과 전문의이며, 남성 건강, 로봇 수술 (다빈치 시스템), 요석 치료를 전문으로 합니다. 미국 베일러 의과대학, 일본 순텐도 대학 병원, 대만 창강 기념 병원에서 국제 펠로우십을 마쳤습니다. 이 사이트의 모든 의학 콘텐츠는 소라위 박사의 임상 경험과 국제 교육을 바탕으로 작성 및 검토됩니다.