once you nail syphilis, theT.
pallidumantibodieswill remain in your blood for years.
It also explains which groups are at high risk of syphilis and when they should seek testing.
Illustration by Joshua Seong. © Verywell, 2018.
They are convenient and confidential, allowing you to test yourself in the privacy of your own home.
Physical Examination
A physical examination may be performed to aid in the diagnosis of syphilis.
The exam may be recommended if your medical history and symptoms are strongly suggestive of the disease.
A syphilis test performed by a healthcare professional is preferred over an at-home test.
Blood Tests
The preferred method of syphilis testing is a blood test.
Two types of tests can detect and confirm syphilis using the same blood sample.
Non-Treponemal Tests
The diagnosis of syphilis starts with a non-treponemal blood test.
This includes the venereal disease research laboratory (VDRL) test and the rapid plasma reagin (RPR).
Both detect antibodies that are produced by the body in response to damage sparked by the infection.
Because of this, a positive result needs to be confirmed with a second, costlier test.
pallidumrather than antibodies produced in response to damage caused byT.
The results of a treponemal test may either be reactive (meaningT.
palliumantibodies have been detected) or non-reactive (meaning thatT.
pallidumantibodies were not detected).
The average syphilis window period is 21 days.
If you get tested during your window period, you might end up with afalse-negative result.
The test can also be performed on tissue samples or nasal secretions.
With dark-field microscopy, the technician will be able to see the corkscrew-shaped bacteria under the microscope lens.
The test may be useful during late-stage syphilis when antibody levels are low and test results are sometimes inconclusive.
Dark-field microscopy is also useful for testing newborns with congenital syphilis.
This is when syphilis is passed from a mother to her unborn child during pregnancy.
By examining nasal secretions under the microscope, the lab can confirm whether the baby hasT.
It may involve additional tests to rule out other explanations for your symptoms.
A positive result from a non-treponemal test is confirmed with a treponemal test.
Less commonly, syphilis is diagnosed with dark-field microscopy.
This is a technique that looks forT.
pallidumin body fluids under a microscope.
A physical exam may also be involved in the diagnosis.
There are also at-home and mail-in syphilis tests that can be purchased online or at certain drugstores.
Although convenient and confidential, they are not as accurate as in-office syphilis tests.
During primary syphilis, the chancre will usually be round and firm with a red crater at the center.
Although painless, the sore will often ooze.
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Centers for Disease Control and Prevention.SyphilisCDC fact sheet (detailed).
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