Rapid plasma reagin

Patients with HIV and syphilis appear to be at greatest risk for clinically significant CNS involvement and may require more intensive treatment than other patients with syphilis.

Diagnostic studies, blood tests, VDRL, that's the venereal disease research lab, that's an RPR, rapid plasma reagent.

And this RPR, that's the most common test that is done for syphilis.

Management.

We're up here.

If that test is positive, lab goes on to do further testing with another treponema specific test as well as a non-treponemal test.

We generally call it RPR.

Also, it is important to remember that treponemal tests initially, even with the genital ulcer, can be negative.

So if you are suspecting syphilis in a person with a lesion, always important to do the swab and repeat the testing after one or two weeks' time where you will see the serological response.

But if it's not early on in the infection and you're doing, say, just an STI screening check, so the treponemal test comes back negative and they're fine.

If it does come back positive, then it's a bit more complex, and that's when many listeners, I'm sure, would be seeking some advice.

But that is where the RPR, rapid plasma reagin, comes in, and that is that test which tends to double and double and double again, and it's a rise and a fall in titer that matters.

In very early disease or initial stages of the ulcer, the RPR test may be non-reactive.

Good point.

This is why all the clinic has to have a non-treponemic test called VDRL or RPR.

If the rapid test is positive, we have to run another test that is the non-treponemic test that give us titles.

And this confirm if you have active syphilis, but also serve to monitor your cure after treatment with penicillin.

If you don't treat this, the mortality is about 10%.

And an interesting thing is that about a quarter of them have a false positive syphilis RPR.

So if you go looking for syphilis, because of course fever and a bit of a rash can look a bit syphilitic, you may get a positive RPR, but that does not necessarily mean that this is treponema pallid.

Callum, why don't you take us through the Sudoku form?

It was great.

You can get septic arthritis, pneumonia, hepatitis, nephritis, meningitis, endocarditis, myocarditis, pericarditis.

And the untreated mortality is reported to be 6-10%, and of note, around 50% have reported to have a false positive syphilis appear.

So it could be a useful diagnostic test, actually, to do your full syphilis testing and do an RPR.

Re-test them in about two to four weeks." And so that's kinda how we go about that process in clinical reality, but for the board exam it's the darkfield microscopy.

That must suck 'cause if you would get, like, an RPR and imagine that being negative, and the patient's like, "Man, I don't know.

I got this, uh, this, this big lesion on my [whistles]"

[laughs]

You retest them in, like, two to four weeks.

It came up positive, and then you confirmed it with a treponemal test, which is the, um...

So we do the RPR, VDRL.

That's usually your non-treponemal test, and then the fluorescent trans, um, the fluorescent, [laughs] uh, treponemal absorption assay or the Treponema pallidum particle agglutination as- agglu- agglutination assay.