I asked a similar question before with a different account, please don't consider this a redundant post. I am a 25-year-old heterosexual male. My last "risky" sexual act was with my now ex-girlfriend. It was two years ago (25-26 months). I used protection during intercourse, but not during oral. We were together for around 3 months, but never tested for STIs before starting our relationship. I am now with someone new, and I just got tested for HIV, Hepatitis B&C, and syphilis. I never thought about STIs before since I am not that sexually active. My current girlfriend and I are getting serious about our relationship, and I want to be confident in my results. For context, I am not from the US.

I know that even if I am infected with syphilis right now, I can't transmit it to my girlfriend at this stage. However, dealing with an undiagnosed infection years later would be much worse. That's what I am worried about. Also, if you could shed a light on the reason why there are so many different estimations on accuracy, I would be glad. And I think a lot of people could benefit from it as well. 

Welcome to the Forum.  Thanks for your questions although I must say, I'm not sure their origin.  The VDRL, like the RPR is a reliable test which has been used successfully for decades.  Because the test detects antibodies and not the bacteria that causes syphilis it has the limitations of all antibody based tests but that said, when used and interpreted by a knowledgeable clinician, few infections are missed and the diagnoses are accurate.  I hope your questions are not based on things you have seen on the internet- the internet is full of misinformation which often leads our clients astray.  ---

Hi Doctor, thank you for the response. You were the one who answered my first question, and told me that no more testing is required to be sure of my results. My main concern is getting a false negative due to that 2 year gap between my last sexual encounter and testing.

I don't have any reason to believe that my ex girlfriend had syphilis. We were together for about 3 months. I didn't notice any body rash during that time which could indicate a secondary stage. I also know that oral transmission is low risk. However, if my test is accurate, I don't have to think about her status anymore if that makes sense. Also, as I mentioned earlier, I wasn't concerned about STIs back then so I didn't even know syphilis is still out there. Therefore, I believe that the tests are the only reliable and accurate judgement on it. I really appreciate your work Dr. Hook. Thank you 

You are misreading the figure you refer to.  Please note that this figure outlines, in a general and somewhat hypothetical fashion, the time course of antibody development in syphilis, NOT VDRL reactivity.  Persons with syphilis have Ia variety of IgG and IgM antibodies in response to their infections.  Since the VDRL detects a variety of antibodies to the syphilis bacteria, on this figure, the VDRL would always be positive at two years.  ---

Thank you doc. As far as I understand, a person who was infected 2 years ago would still have enough antibodies in his blood for a VDRL or RPR test to detect it even if the disease is in the latent stage. Therefore, a reverse algorithm testing is unnecessary. It can be utilized in people who were infected at least 10 years or more, or people with other issues that might change the course of the disease. I am sorry for the graph. I do not question your experience or reasoning in any way. Your and Dr Handsfield's experience was the reason why I came to this website to begin with. I'd consulted a few doctors from my country before coming here, but I just want gather as many different view points as I could. I can rest easy from now on, and focus my relationship with my current girlfriend, and hopefully, my wife in the future. 

I'm pleased that you found the information I provided helpful.  It is time for you to move forward without concern about syphilis.---