Syphilis RPR VDRL false positive?

[dshrfrshr]

Hi everyone. So I recently moved and changed doctors, and had new blood tests done.  Just got a call my RPR test was reactive and that I need to make an appointment for the three shot treatment.  It's entirely possible I contracted it, but a year ago, I had a false positive test, where my RPR was reactive, but a VDRL at the same time came back non-reactive.  They did a follow up RPR a month later, and it came back not reactive.  I have never previously been  diagnosed with syphilis., but have been treated for Chlamydia and Gonorreha. Should I request a follow up test?  The butt shots don't sound fun if they aren't necessary. 

[bocker3]

An RPR is a screening test and as such is not a definitive test for syphilis infection.  Most labs should automatically do a confirmatory test like FTA-ABS to rule out a false positive RPR.

A screening test, like RPR, is designed to be very sensitive, but not as specific -- meaning one expects more false positives from a screening test.  This is why one follows up a positive screening test with a confirmatory test, which should have specificity for what is being tested.

I would not have the shots until I had a confirmatory test -- it is possible they did it and the results were just conveyed incorrectly to you.  As I said, in the US, most labs would automatically do this confirmatory test.

Edited to add:  VDRL is also a screening test and thus not definitive.

Mike

[aaware72]

I also had a false positive when I tested HIV+  They put me on antibiotic in case I actually did.  They did a blood test and I was negative.  However, I'm allergic to penicillin so I take pills instead of those big shots in the ass..

[dshrfrshr]

Got a call back from my doctor saying they did do a confirmatory test (maybe a FTA-ABS) that also showed it was positive, and that I had a titre level of 1:64 (bad??)  He still wasn't 100% sure if he was 100% sure, so he told me an infectious disease doctor will give me a call back.   Haven't noticed any rashes, bumps or sores.  Ugh, those shots are probably not avoidable. 

[bocker3]

No -- it is probably an RPR titre.  the 1:64 result is saying that the reaction indicates a pretty strong positive result (they dilute your blood sample and retest, if still positive they dilute again, 1:1 is straight blood, then 1:2, 1:4, 1:8 and so on -- 1:64 is saying even a very dilute sample is showing a positive reaction to this SCREENING test.

A high titre like that strongly suggests a real infection, but, if it were me, I'd still insist on a more definitive test.  Though, I'd probably take the shots in the meantime (after a new sample is drawn).  I'd insist on this test to know for sure, but would take the shots because it probably is real and I'd want to kill it sooner vs. later.

However -- I am not a doctor -- just a former lab tech.

Good luck,
Mike

[Ann]

Haven't noticed any rashes, bumps or sores.   

That's one of the big problems with syphilis. The initial sores in primary infection are painless, so they very often go unnoticed. You could have one in your rectum, throat or even the underside of your scrotum or penis, and be totally unaware it was there.

The rash that may accompany secondary syphilis isn't always noticeable either, and can manifest so unobtrusively or appear so briefly that it may as well not be there.

Syphilis used to be commonly known as "the great imitator" because it can mimic symptoms of many other things, and the symptoms are often dismissed as "nothing".

Many STIs can be present with no obvious symptoms, so the only way to know for sure is to test, and for some things like syphilis and hep B, a definitive diagnosis isn't always one simple test. Unfortunately.

Good luck with it all.

[dshrfrshr]

Thanks for the answers everyone, really can not say how valuable a resource this forum has been in dealing with all the different aspects of HIV.

In regards to the Syphilis test, I never heard back from an infectious disease doctor, but given then holidays the next couple weeks I probably will not hear back for a while.  Im thinking I will request a new rpr and confirmatory test, and make an appointment to start the shot regiment, thanks for the input Mike

I've been seeing someone for a 2 months right now, going to cut off sex for now, and tell him to get tested at the public health clinic before rushing off for treatment.  He's the top in the relationship, and hasn't had any symptoms.  Don't want to rush him into thinking he's caught it if its not the case.

Minor detail, in my younger partying days (2009-mid 2013), chlamydia, gonorrhea and I were an unstoppable trio.  In that 2-3 year span, I don't think I had a test come back non-reactive for one of them (6 or 7 tests at least too). Lady Syphilis never joined the party tho.  After I realized that the public health clinic would give partner packs too, I would load up on my azithromycin, and skip the visit to the clinic and just take those two pills every couple months (probably not the correct thing to do in retrospect).  Im wondering if perhaps I acquired syphilis at that time, had it go undiagnosed, and simply treated it with the "self-prescribed" azithromycin (which would explain why a confirmatory test would show I have been exposed).  Or maybe I did catch it from the hot escort who did me bb on a motel balcony last July.  Better taking a few shots to the rear than losing my vision in maintaining this idea Im somehow not susceptible to syphilis. (Didn't work so well that first time with condoms and HIV)

Not exactly related but maybe you guys and girls can offer some advice, Ive left my previous doc and gay-friendly public health center for a more podunk, small town type of place.  Being that I stay on the "bottom" bunk of the bed, I was disappointed my labs only had me do a urine test.  When I meet with my doc, can I request a rectal swab as well? (or can i just stick a finger back there and swish it in the pee sample? Im slightly serious)  Also they used to exam my anal/rectal area once a year for any abnormalities.  They actually did a culture, but luckily it came back ok (benign might be the right term?)  Are these types of tests commonly done outside the NYC/LA/SF type areas?

Thanks again for all the help!

[Gracie2]

I also had a false positive when I tested HIV+  They put me on antibiotic in case I actually did.  They did a blood test and I was negative.  However, I'm allergic to penicillin so I take pills instead of those big shots in the ass..

Same here.  I am allergic to penicillin also so I take pills instead.