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Quick GuideSTD Diagnosis, Images, Symptoms, Treatment
What tests are used to diagnose syphilis?
There are two types of tests used to diagnose syphilis: treponemal tests (that identify antibodies to the causative organism) and non-treponemal tests (that identify the body's response to the infection but not to the organism itself).
The blood tests used to screen for syphilis are called the Venereal Disease Research Laboratory (VDRL) and Rapid Plasminogen Reagent (RPR) tests. These tests detect the body's response to the infection, but not to the actual Treponema organism. While these are good screening tests, they are not specific enough to establish the diagnosis. These tests can give false-positive results, so a positive screening VDRL or RPR test must be followed by a treponemal test to detect the organism.
A number of different tests are available that detect antibodies to Treponema pallidum bacteria. Examples include the microhemagglutination assay for T. pallidum (MHA-TP) and the fluorescent treponemal antibody absorbed test (FTA-ABS). These tests can confirm the diagnosis of syphilis if a nontreponemal test such as VDRL or RPR is positive.
What is the treatment for syphilis?
Penicillin is the treatment of choice for syphilis in all stages. One intramuscular injection of long-acting benzathine penicillin G (2.4 million units) is sufficient for a person who has primary, secondary, or early latent syphilis. Three doses of this drug at weekly intervals are recommended for individuals with late latent syphilis or latent syphilis of unknown duration. While treatment kills the bacteria and prevents further organ damage, it will not reverse damage to the organs that has already occurred. Treatment with penicillin is safe during pregnancy.
What are the potential complications of syphilis?
As mentioned, untreated syphilis spreads throughout the body and causes complications with various organ systems. Some of the better known complications of late syphilis include blindness, dementia, aortic aneurysm, deafness, stroke, and other complications related to spread of the infection to the brain. Late stage syphilis can cause fatal complications.