Avatar universal

Positive VDRL and negative TPHA

I had unprotected oral sex in August (7th and 24th), and noticed a bad sore throat and swollen cervical nodes by September 6th. This didn’t subside for many weeks. I was put on amoxicillin for five days, which didn’t help. An ENT put me on cefalodoxime which I’m still taking but it hasn’t helped. I also noticed a small painful pimple on my anus (but I don’t practice anal sex). I did an HIV and VDRL rapid tests on October 2nd (nearly 6 weeks from last incident). HIV was negative but VDRL was positive. The ENT specialist wanted to confirm this and asked me to repeat VDRL and HIV in addition to TPHA at a different lab. The HIV (this time a combo test), came out negative exactly six weeks from the day of exposure. The TPHA was negative too. However, the VDRL/RPR is positive at 1:32 dilution. Does this mean I was recently infected by syphilis and TPHA is not showing it? Or does this mean the VDRL is a false positive due to some other illness that is causing my sore throat and swollen nodes? I received my second dose covid vaccine (AstraZeneca) on the 10th of September. Could this have resulted in a false positive VDRL result? Or do I just have syphilis and I must get treated?
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4859015 tn?1360119889
VDRL test may give false positive results and it happens not so rarely. There are many causes for this, and a vaccine is unlikely one of those.
Anyway, VDRL is an indirect test, while TPHA is a specific treponemal test which is always more specific and more sensitive.
The pimple on your anus is unrelated, while there may be an unnoticed primary chancre in your mouth (assuming you gave oral sex). If you only received oral sex, you don't have to worry about syphilis.
No worries on HIV either.
As AuntieJesse said, positive VDRL plus negative TPHA should be considered a false positive. But there is a tiny possibility that TPHA test was wrong, so the doctor must be careful and must be 100% sure to rule out syphilis.
If you gave unprotected oral sex, I suggest doing another syphilis test, preferably a different combo (RPR + EIA or TPPA), just make sure it includes a specific treponemal test.
I wouldn't worry much since VDRL test is notorious for its false positives.
Helpful - 2
Sorry. I posted a comment below. This was meant for you: “ I gave a blowjob and rimmed as well. I have an appointment with an infectious disease specialist and I’ll be sure to tell her I’d like to do a treponemal test again.”
Okay, so there was a risk for syphilis.
It is a good idea to see a specialist. Do another test and keep us informed on your progress.
207091 tn?1337709493
What is happening with the VDRL titers? Are they going up? Down?

The standard is that if you have a positive VDRL or RPR and a negative TPHA, the VDRL is a false positive.

I don't know that we have enough info on the covid vaccines to know if that contributes, but historically, vaccines haven't caused false positives. Things that can are autoimmune disorders, Lyme Disease, some tropical diseases like malaria, HIV.

Have you ever had syphilis before?

If you don't practice anal sex, the sore on your anus can't be a syphilis sore. Sores appear at the point of infection. Syphilis sores are flat, round and painless.
Helpful - 2
I’ve done VDRL tests in the past but they were negative. The last time I did it was 2 years ago. If my current six combo test for HIV reveals a non-reactive result, can HIV be ruled out as a cause for VDRL false positive? I have never had syphilis before as far as I know.
Avatar universal
Do you think I should ask for a neurosyphilis test as well? Also, should I ask her to repeat the penicillin injections after the doxy course is completed? Yes, TB prevalence is high in India. Not sure about LGV. And when should I test for the titers?
Helpful - 1
4859015 tn?1360119889
Sad to hear you have syphilis; good news it is very curable. I have never heard of a negative TPHA turning positive, so I assume there was some human error involved. It was a good call to do another test. FTA test is not necessary, time to treat syphilis.
It is not possible to say for sure how long you have been infected. VDRL titer is not very high, so it may still be a new infection (end of primary stage, from that exposure 6 weeks ago). It might be an older infection, but I doubt you missed it a rash since 2019. I wouldn't worry about your titers, just do the treatment.
Every new syphilis case must be tested for HIV.
Your HIV RNA test must be procedural, but, since your TPHA test was botched, there may be something wrong with the lab which did the initial round of testing. I strongly recommend retesting for HIV at a different lab, but always keep in mind that only antibody test (not RNA) is conclusive. I would do another DUO test instead in a few weeks and wouldn't hurry.
You definitely have an infection (syphilis) and it may influence your lymph nodes and CBC, so no need to worry much on that. Syphilis is associated with enlarged lymph nodes, all over the body too, when secondary stage starts.
Multiple small lesions on your genitals might be genital herpes, AuntieJesse would probably tell more on that.
Helpful - 0
Hi @auntiejessi and @grobick2000. I am sorry I didn’t get back to you because I have had some very rough days and I didn’t want to post repeatedly. I started penicillin (2.4 million, 3 times) on the 11th of October, and took the remaining doses on the 18th and 25th. My dermatologist (not the infectious disease specialist. I long abandoned the "infectious disease specialist" because she started to insist I must get an excision biopsy done for my lymph node and refused treatment for syphilis until I did all the tests for TB including GeneXpert) curiously put me on doxycycline as well. She initially asked me to take 100 mg twice a day for 3 weeks, and when I went for a review yesterday, she asked me to take 100 mg for 3 more weeks, after the initial 3 weeks of 200 mg/day gets completed next week. I missed a dose this morning and I took two doxycycline capsules at dinner to make up for the missed dose. I doubt it was a smart idea. I read that penicillin interacts with doxycycline, which renders penicillin ineffective. My symptoms have improved and my lymph node has reduced in size. My rashes have begun to dry as well, and the ulcers have all vanished. How do I make sure I don’t have neurosyphilis or ocular syphilis? Also, I got tested again for HIV at a different lab close to 7 weeks from the date of exposure. It was negative. This was a CMIA combo test. The dermatologist insists I need to test after 3 months and this result is not reliable as it is too early. I am understandably anxious. Can I still have HIV or should I believe the 7 week combo test results? As penicillin may have been ineffective due to doxycycline, should I continue to taking 200 mg after the 3rd week instead of 100 mg as advised by the dermatologist? She also suspects LGV, although no tests were conducted for that. I think the doxycycline was prescribed for the presumptive LGV infection.
Yes, it seems like doxy may interfere with penicillin - https://www.medicinenet.com/amoxicillin_amoxil_vs_doxycycline_vibramycin/article.htm

The good news is that doxy is the second line treatment for syphilis, and is used in people who are allergic to penicillin, so there's that.

The only way you'll know if it's working for you is to test again and see your titers. Symptoms improving are a good sign, but it could be slowing the growth, not killing the bacteria.

I'd trust the 7 week combo test. You may need to do a 3 month to shut her up, but I'd expect it to be negative.

The only way to know for sure if you have neurosyphilis is to test your cerebrospinal fluid (CSF).

I can't tell you to stop or continue the doxy. That's something you need to address with your doctors.

Why are they suspecting LGV? And TB? I mean, you have syphilis - you aren't a walking infection of every disease known to man. Are you in an area that has high incidence of both?

Sorry, I again left a comment below. Also, could you please tell me if every person who is diagnosed with syphilis should also get a spinal tap?
First of all, treatment for syphilis is penicillin OR doxy, not both. I have read thousands of papers on syphilis treatment but have never seen such treatment regimen.
But the good thing is it should have worked. Your symptoms improving is a good sign.
I see no point in continuing doxy after the full course you've already taken. Now it is time to assess the treatment effect.
Now you should keep monitoring your VDRL titers every 3 months for a year. If the titers keep going down, the treatment is successful (it should be). You need to achieve 4-fold decrease of VDRL titers (from 1:32 to 1:8 or lower) to be completely cured. And don't do any treponemal tests like TPHA anymore, they are no use.
Now for the much feared neurosyphilis. No, not every person diagnosed with syphilis needs spinal tap. Neurosyphilis is quite rare and it normally develops late in the course of disease. While most textbooks say scary words about "may happen at any stage", it almost never happens that early as in your case.
I strongly advise against testing for neurosyphilis. It would do more harm than good in your case.
And stop doing all those HIV-tests. As for TB, don't do the biopsy yet. Wait for a few months.
Thank you. The dermatologist said she was prescribing the doxycycline for other possible STIs I might have. She said suspected a concurrent LGV. The prescription says “mixed STI. Syphilis + LGV ?”. Of course, no tests were conducted for LGV.

Will the doxycycline affect penicillin’s efficacy, and thus render this particular treatment a failure? Also, as many textbooks mention neurosyphilis can occur at any time, is it possible for syphilis to evade 3 shot penicillin/28 day doxy and remain in the central nervous system only to strike back decades later? And what harm may the spinal tap cause?
It is quite difficult to diagnose LGV, the test is quite expensive, so the treatment is usually presumptive (doctors suspect LGV so he/she starts the treatment).
Now it is quite clear.
Why do you think your treatment was a failure? Doxy alone is very effective against early syphilis. In your case you kinda double-covered your syphilis, so I would never suspect a failed treatment.
My point is you should first see the VDRL titers (no sooner than in 2 months) and then you can assess the treatment success.
You asked "is it possible for syphilis to evade 3 shot penicillin/28 day doxy and remain in the central nervous system only to strike back decades later?"
Theoretically, yes. Syphilis is so well studied, that all sorts of treatment failures/late comebacks are documented. But you are about a million times more likely to die from a sudden stroke/heart attack in your early 30s. And about a thousand times more likely to be bitten by a snake or a rabid dog. Can we really cover all the risks?
You asked: "And what harm may the spinal tap cause?"
A missed tap may render you paralyzed for life (risk is very low, though). You will feel sick for a few days and the test results will definitely come negative after all those antibiotics you had. The general principle of medical science is "Anything that is not necessary is harmful". A spinal tap is really not necessary in your case.
I understand what you are asking here - will the doxy make the penicillin less effective, thereby making your treatment a failure?

I don't think so, because your symptoms are getting better, and because doxy is also effective at treating syphilis. We can't ever tell if the doxy is making it less effective - and it can do that, apparently - but if it is, it seems like the doxy will be backing it up, so to speak, in your case, since your symptoms are improving.

I totally agree with grobick about the spinal tap. There is no evidence of neurosyphilis here, and you are getting treatment. The risks outweigh the benefits of such an invasive test.
Hello! hope you both are doing well. I am not. I eventually did an RPR/VDRL test on November 17th (4 weeks after my last penicillin injection). The titer had reduced from 1:32 to 1:8. The doctor declared me "cured" and sent me away, after asking me to get vaccinated for hepatitis b. I took two doses of hepatitis b vaccination on November 24th and December 24. I drank a lot on the Christmas day and panicked the next day. So I took another dose of the hepatitis vaccine. My booster dose is due in May. She advised me to get gardasil after my hepatitis b booster dose. Anyway, I met a guy last week, and we hugged and masturbated each other. We wore condoms and blew each other. We were mindful of my syphilis treatment and how I don't want to screw that up. However, since that night, I developed shotty lymph nodes (which I already had during my severe illness in September-October 2021. They had reduced in size and were barely perceptible. Now, all of a sudden, I can palpate them and a couple of them are matted and but they are tiny. They also feel warm and tender to touch. Taking paracetamol helped reduce the pain and the feverish feeling. I also have itchy skin all of a sudden, and a couple of broken pimple-like sores on my face. I am wondering if my syphilis treatment last year failed and it is now reactivated. Or did I catch it from that person although we had safe sex? It was not even sex honestly. Just some oral fooling around with condoms on but we did hug while naked, and I know syphilis can spread if there are sores on the body. I am planning to do a VDRL test again to check if the titer levels have reduced or increased. What could be the problem here? I currently have those mild shotty lymph nodes that hurt a bit in the neck, runny nose, very mild sore throat, and a feverish feeling all of which improve with paracetamol. But this is how the syphilis  illness started in September last year.
You wouldn't have syphilis symptoms so soon, but did you think of covid? That's what I'd think of first, to be honest.

If you're in an area where covid is still an issue -and I don't know of an area where it isn't - then I'd think that first, and get tested.

You used condoms for oral, making your risk for syphilis very low. I understand your panic, but test for covid now, and maybe syphilis, just to see where your titers are, but I'd bet more on covid or the flu or something.
Yes, I did think about Covid but the symptoms are so similar to what I experienced in September. Do you think it's possible my syphilis treatment failed last year and now it is reactivated?
I don't know that, but it's doubtful. Your titers dropped the 4-fold required for successful treatment, so it would be really unlikely that treatment failed. The only way to know is to test. Get a covid test and a syphilis test - cover the bases.

Don't do yourself a disservice, though, and only focus on syphilis.
Hi. The VDRL test came out negative. Could it be real or should I test in another lab?
And the person with whom I made out got a Covid negative report
Yes, it could be real. Some people will still have a low titer, like a 1:1, but some will test negative. Looks like you're negative. :)

Is the person you made out with the only person you've been around? Covid is airborne. You could get it from someone at the store, at work, etc. You don't have to have kissed them to get it. It's good that the person is negative, but that doesn't mean you are/were.
Yes he was my only exposure and I don’t have any symptoms at the moment except a very dry nose. Also, if my RPR/VDRL is non-reactive at one lab, could it be positive in another? Should I test again in a different lab?
Also, what’s the difference between “ RPR ( VDRL ) (Slide flocculation)” and anti treponemal antibodies CMIA? And I assume I no longer need to do a TPHA?
RPR and VDRL are non-treponemal tests. The syphilis bacteria is called Treponema pallidum, so these tests are looking for non-treponemal antibodies - namely, the IgM and IgG antibodies. If these tests are positive, they do a treponemal test to confirm.

The treponemal tests look for antibodies specific to the T pallidum bacteria.

If you have a negative RPR or VDRL, you do not need further testing.


Hi. Two weeks ago I got drunk and blacked out. I had a cut on my finger and I remember jerking off another man. My fingers came into contact with his urine and cum. The next day I took 400 mg of doxycycline and continued to take 200 mg for 14 days (until day before yesterday). Day before yesterday, I developed a sore throat similar to what I had when I was first diagnosed with syphilis. Could I have syphilis again, in spite of taking doxy as prophylaxis/treatment for primary syphilis (although I don’t know if I was reinfected)?
I had a cut on finger just a few hours before the encounter. Not a large gash but an open wound with broken skin. Also, due to the blackout, I can’t remember the exact details of the act. Maybe I blew too (he denied), who knows?
Handjobs don't transmit syphilis. You had no risk. Urine and semen don't transmit syphilis. Syphilis is transmitted by oral, vaginal and anal sex, or direct, unclothed skin to skin contact of mouth to genitals, genitals to genitals, or genital to anal.

Sore throats are caused by all kinds of different things - strep throat, allergies, covid, dry air, tonsillitis, colds, flus, pollution, reflux/GERD, etc., etc.

I understand how this traumatized you. Please know that the more often you take an antibiotic, the more likely it is that you'll be resistant to it when you need it. I'm also concerned about your alcohol use. Drinking to blackout is almost always the sign of problem drinking, and when you drink too much, it seems like you end up concerned about what happened sexually.

I don't want this to end up as a vicious cycle for you. Have you considered counseling to deal with all of this? We just want you to be healthy and happy.
Hi I did get some therapy for my anxiety but the therapists don’t seem to understand the real risk that gay men have. They mostly dismiss our worries as anxiety. By the way, I went for a routine VDRL and HIV test and while the HIV test is negative, they aren’t releasing the VDRL report. The same lab released the report within hours in January, when it had turned non-reactive from 1:32 and 1:8 (after treatment).

Between January and May, I received a blowjob but took 14 days of doxycycline twice a day. I met another guy and we masturbated each other and kissed each other. I took doxycycline for 14 days again because I read kiss is a risk and doxycycline for 14 days is enough to cure primary syphilis. Yet again, I met another man and we masturbated and kissed each other. This time I didn’t take the doxycycline and convinced myself I’m anxious. I also kissed another guy a few weeks ago. I’m suffering from balanitis since once month for no good reason (no infection apparently, according to the doctor). So today I went and did te HIV and VDRL/RPR. HIV came out negative but they aren’t releasing the VDRL/RPR. This only happens when they need to repeat the test to confirm a positive result. Do you think I was at risk from any of the activities I mentioned above to go from a negative RPR/VDRL to a positive one? Or could a negative RPR/VDRL turn positive for no good reason? I am suspecting I wasn’t treated adequately and I have neurosyphilis.
Okay, real talk time.

First, your balanitis could be fungal and it could be a result of all the doxy you're taking. You really need to stop taking that every time you do something.

Kissing and masturbating is NOT a risk for syphilis.

Oral sex is a risk for syphilis, but you knew that already, right?

I don't know why they aren't releasing your syphilis results, but it's quite a leap to go from testing negative to thinking that you had a treatment failure and have neurosyphilis.

You need to find a therapist who understands gay men and risks. Are you in the US? There are plenty who specialize in LGBTQ issues. (You don't have to say where you are.)  Search LGBT therapists near me and see what you find.

If you are going to panic after every encounter, maybe don't have any encounters for awhile. Taking antibiotics that often when you don't need them isn't good for you, and they will be less effective when you need them.

Let us know what the test results say, and look for a therapist.

I live in Bangalore, India. An almost-westernized city. So if kissing and masturbating aren’t risks, and if I’m covered for the oral sex I received because I took doxy (the person had tested negative on VDRL by the way), then the only real explanation why they’re not releasing my results could be due to something innocuous like lack of personnel (but they released HIV) or, my titers are fluctuating. In which case, I don’t know what to do. I’m sorry I do have anxiety and PTSD and I plan to abstain from sex as I can’t deal with this anymore. And it’s impossible among gay and bisexual men to be sure they’re not STD-free unless they agree to test. Right now my only worry is the delay in results, and the reasons behind it. Usually, the delay suggests a positive result.
Sorry but I had to add, I received my booster shot for hepatitis B today (the third one). I plan to take the Gardasil from next month onwards.
There could be a dozen reasons why they aren't releasing your results - maybe a machine malfunctioned, maybe they are understaffed today, maybe the person who reviews the syphilis lab reports had to leave early with a dental emergency -  we just never know.

You shouldn't just sit and worry about the results, so here's some homework, so to speak. I found some counseling possibilities. I know nothing about any of them, except they are in India, mostly in Bangalore.

I found this in Bangalore - can't vouch for him (or his name lol) -


Also: https://www.pinklistindia.com/mentalhealth/



Check them all out. :)
Avatar universal
I gave a blowjob and rimmed as well. I have an appointment with an infectious disease specialist and I’ll be sure to tell her I’d like to do a treponemal test again.
Helpful - 0
I agree with continuing to investigate this. Good luck and keep us posted. :)
I did see the infectious disease specialist who was quite eager to prescribe a volley of tests for chlamydia, gonorrhea, herpes, EBV, toxoplasmosis, hepatitis B and C, and finally three syphilis tests: VDRL, TPHA, and FTA AbS. She’s also asked for a neck ultrasound for the swollen nodes and said I will need a biopsy too (this of course shook me). And an HIV PCR RNA test because she doesn’t trust the combo test at six weeks. Isn’t it confirmatory at six weeks? Or is it possible that my false positive VDRL is related to a false negative HIV combo test?
Wow, that's a lot of tests. I am not sure every single one is necessary (herpes and EBV are certainly not), but okay.  The doctor is looking for the infection that makes your VDRL positive and toxo, EBV and hepatitis might be the culprits.
Three syphilis tests is a good call. You should expect positive VDRL and negative TPHA and FTA.
I am not an expert on HIV testing, but I see no reason for "not trusting" DUO test. False negative 4th gen HIV tests are quite rare. The gold standard is still an antibody test at 12 weeks, but you shouldn't worry about HIV.
Let us be patient and wait for those test results. Keep us posted, please.

Okay, I can understand the HIV test as procedural, because your syphilis tests don't make much sense. I wouldn't expect that to be positive, but she probably has to run that to rule that out.

A biopsy of your lymph nodes? I'm not sure I understand that one, but I'm not an infectious disease doc.

I'm sure these are just routine tests to rule things out, and I see no reason to expect your herpes, hep B and C tests, and probably EBV to be positive. Hep C is only transmitted by blood, and usually by sharing needles for drug use. You've likely been vaccinated for Hep B.

A note on the herpes tests - there are false positives on the hsv2 IgG tests. If your test result is positive, but below a 3.5, ask them to confirm it with a Western Blot. That's standard of care now, per the CDC.

Keep us posted.
Some bad news. VDRL is positive at 1:32 dilution. And TPHA is positive at 1:2560 dilution. I couldn’t find a lab that offers FTA antibodies. So i think that settles my doubt. The dermatologist I spoke to (not the infectious disease specialist) said my titers look like I’ve been infected for a very long time. Is that true? My last VDRL in 2019 September/October was negative.

I got the results of few of the many other tests I underwent. My HSV 1 and 2 (it doesn’t say which one is positive, one or two) IgM is reactive at 1.58 but IgG is non reactive at 0.78. My toxoplasmosis is reactive too (IgG - 41.9). The IgM is non reactive at 3. The Cytomegalovirus IgM is reactive at 56.20 but the IgG is non-reactive at 5.90.

Hepatitis B and C are non reactive. No I am not vaccinated against Hepatitis B yet.

I did a fine needle aspiration of my lymph node and the radiologist commented it looks like an infection. The results of the FNAC (needle biopsy) should be out tomorrow. The neck ultrasound revealed bilateral cervical lymphadenopathy and it says the cause seems to be an infection. The radiologist who did the ultrasound said it looked like tuberculosis and asked me to do a chest X-ray (turned out to be normal) and a complete blood count test. The CBC shows Red Cell Distribution Width as 11.50 (just lower than the lower range of 11.60). It also reveals a total leukocyte count of 11.70, which is above normal. Under differential leukocyte count, lymphocytes have been recorded as 17.50 which is lower than normal. Neutrophils are 8.51, slightly above normal.

I’m worried about the high titers of syphilis and also the positive Herpes result. I have multiple small lesions on my genitals. They have the same color as my skin but they shine as if they are dry. Some of these lesions are weepy as well. When they dry, they’ve left a wart-like lesion that peels too. Is this herpes or genital warts?  And the infectious disease specialist wanted me to do an HIV PCR to rule out completely. Is it really necessary in my case, considering a negative HIV combo report at six weeks?
Wow - they are just throwing it all at you, huh?

Ok, we'll start at herpes, because that's easiest to address. The IgM test looks for "new" antibodies. They fall off, so to speak, by about 6 weeks. So, this test shouldn't have been done on you. The other thing about the herpes IgM is that it is a terrible test. It is inaccurate and unreliable. Trust the IgG result, ignore the IgM. I'm surprised your ID doc even did that test. We've known for years it's a bad test.





Okay, "very long time" is subjective. The longest time it could be is 3 years because you had the negative test in 2019. I've seen longer. All it means is that you will get a series of 3 shots.

"Bilateral cervical lymphadenopathy" means you have swollen glands.

https://www.osmosis.org/answers/cervical-lymphadenopathy - this has a whole paragraph about how cervical lymphadenopathy can often be confused with cervical lymphadenitis, and how the latter can be caused by TB. Maybe  the radiologist got confused?

Usually, when something is just under or just over the range, it's not a concern, but again, I am not a specialist in any of this stuff.

The lesions - not sure what they are, but they could be molluscum. Warts don't weep, and herpes doesn't shine and isn't skin colored. Has the doctor seen them?

A lot of what this doctor is doing isn't necessary, like the hep tests. I don't see a need for the HIV PCR, if you had a 4th gen DUO test. I hope you have good insurance, if you're in the US.

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