Can Syphilis test be false negative if I take the test 4 years after a risky event?

[Hello1580]

Hello, I just wanted to ask one question and I’m extremely worried about this.

I had a oral sex with a old man (who seems like he’s more than 50 years old) and he DIDN’T ejaculate. I don’t specifically remember if he had any showing symptoms of Syphilis. I will just write down all the details.

He and I both DID NOT take shower before this event, which is not very good in terms of hygiene. (Does this increase the risk of Syphilis?)

Also as I mentioned above, we only had a mutual oral sex (for like... 25 mins?) and he didn’t ejaculate, but I did ejaculate.

And then he was going to do anal sex with me, and I let him do it LITERALLY 5 seconds with condom, and refused it and he took his penis out.

And then I massaged his penis for 3-4 minutes and the event was finished. We both took shower together and he gave me an oral job during the shower for like 15 seconds.

After the event I never had a symptom that I could think of for the last 4 years.

Now my main question is I am going to take a RPR test and I’m worried what if the test says false-negative even though I am positive, because I’m on my late latent stage of Syphilis? I read so many articles that people who test for Syphilis on their late latent stage might get false negative as a result even though they’re actually positive. I just want to hear from a very professional person who worked for a long time on this field.

Thank you so much for your answers. I appreciate them a lot!

[GuitarRox]

You are worried about this event that happened 4 years ago, correct? And all you had was mutual oral sex.   Remember that syphilis is only transferred from sore to skin contact. Remember any sores? You never got the unmistakable sore?  Also, if you've taken a variety of antibiotics over the past 4 years such as penicillin based or doxycycline, you'd have treated a syph infection inadvertently. But I don't think I'd worry about this. If you are, go to a clinic and get a full std screening.  That never hurts.  

[Hello1580]

Thank you so much for your answer. I haven’t taken any antibiotics in my life. Is there any possibilities of false negative when you take test 4 years after the event? I read it from healthline website that if its late syphilis one might get false negative.

I’m going to take both RPR and TPHA test in a few days. I’ll wait for your answer.

Thanks!!!

[Hello1580]

I also don’t recall a significant sore on my body, but I don’t remember how the guy’s body looked like.

[auntiejessi]

No, you'd still have antibodies if you were infected with syphilis 4 years ago.

"Late" syphilis is longer than 4 years.

You haven't had any symptoms? Any sores on your genitals or in your mouth? A rash on your body? The rash is hard to miss.

I'd be very surprised if you had syphilis. It's not that common, and "old" doesn't mean higher risk. It actually may lower the risk somewhat, as that age group isn't as high risk for STDs like others are. I don't know how old you are, but 15-24 year olds have the highest rates of infections.