| NON-TREPONEMAL TESTS | Syphilis infection leads to production of non-specific antibodies that react to cardiolipin. There can be a lot of false positives (cross react with other things). You can also have the prozone/hook effect (which is a false negative due to very high titers). Non-treponemal tests can be reported as a titer. | RPR
VDRL (ONLY ONE USED for CSF fluid) |
| TREPONEMAL TESTS | Looking for SYPHILIS ANTIBODIES specific for the spirochete. NOT reported as a titer. It is Reactive or Non-reactive. These REMAIN positive usually lifelong. | FTA-Abs
TPPA EIA Testing – this is what we do |
The prior testing algorithm was a NON-TREPONEMAL TEST followed by a TREPONEMAL TEST. This changed a few years ago due to a study from New York City in which they found it to be more cost-effective to do a TREPONEMAL TEST followed by NON-TREPONEMAL TEST in high prevalence areas. This is why we at VALLEY switched the way we test for syphilis.
SYPHILIS TESTING AT VALLEY:
- Syphilis EIA Antibody (TREPONEMAL) à If Positive go to Number 2
- RPR with Quantification (NON-TREPONEMAL)
Other pearls:
- Some Patients remain Serofast (low titers such as 1:2) even after treatment
- Remember that the Treponemal Tests STAY positive lifelong, so it is important to ask if they have had syphilis before, what their titers were, and whether they were treated. Then you go by the RPR titers and compare to see if the RPR titers were higher than before.
- LP results for syphilis usually show a lymphocytic pleocytosis (<100 total cells, > 5 Lymphocytes), Elevated protein > 45 mg/dl)
- We only send the VDRL for the CSF fluid (occasionally you can do a treponemal test as well, but not routinely done)
- Neurosyphilis can occur at any stage
- Ocular syphilis can cause anterior uveitis, posterior uveitis, or panuveitis
| Clinical Features | Treatment | |
| Primary Syphilis | Painless Chancre which appears at the site of inoculation, infectious | Penicillin G 2.4 million Units IM x 1 DOSE |
| Secondary Syphilis | Generalized non-pruritic rash involving palms/soles, infectious, also systemic symptoms including fatigue, diffuse LAD, fever | Penicillin G 2.4 million Units IM x 1 DOSE |
| Latent Syphilis
|
Early Latent (seroconverted within past 12 mo) | Penicillin G 2.4 million Units IM x 1 DOSE |
| Late Latent
|
Penicillin G 2.4 million Units IM x 3 Doses qweek | |
| Tertiary Syphilis | Gummas (granulomatous lesions)
Tabes Dorsalis Ocular Syphilis Aortitis Neurosyphilis |
24 million units of Penicillin daily for 2 weeks (continuous pump) for neurosyphilis, otherwise 3 doses of weekly PCN G |
SCVMC IM Chief Resident Blog 