Table of ContentsView AllTable of ContentsAt-Home TestingPhysical ExaminationLabs and TestsDifferential DiagnosesWho Needs to Be Tested?Frequently Asked QuestionsNext in Syphilis GuideHow Syphilis Is Treated
Table of ContentsView All
View All
Table of Contents
At-Home Testing
Physical Examination
Labs and Tests
Differential Diagnoses
Who Needs to Be Tested?
Frequently Asked Questions
Next in Syphilis Guide
Once you have syphilis, theT. pallidumantibodieswill remain in your blood for years. Based on certain test values, the lab may be able to tell if the infection was recent or occurred years ago.
This article looks at what is involved in the diagnosis of syphilis, as well as the various testing options available for at-home or in-office use. It also explains which groups are at high risk of syphilis and when they should seek testing.
Self-Checks/At-Home Testing
One of the major drawbacks to STI screening is the discomfort people feel when asking their healthcare provider for a test. Some people may even avoid testing for years until the infection suddenly turns severe and becomes more difficult to treat.
For this reason, some public health officials have endorsed the use of at-home syphilis tests that you can purchase online or at certain drugstores. They are convenient and confidential, allowing you to test yourself in the privacy of your own home.
There are two types of self-tests commonly used for the diagnosis of syphilis:
How to Choose an At-Home TestThere is little federal regulation of at-home STI tests. To better ensure accuracy and reliability, only purchase products that bear a Clinical Laboratory Improvement Amendments (CLIA) certification.
How to Choose an At-Home Test
There is little federal regulation of at-home STI tests. To better ensure accuracy and reliability, only purchase products that bear a Clinical Laboratory Improvement Amendments (CLIA) certification.
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.
Common signs and symptoms of syphilis include:
While symptoms like these are suggestive of syphilis, only a blood test can definitively diagnose the infection.
Common Signs and Symptoms of Syphilis
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
While non-treponemal tests are inexpensive and easy to use, they are prone tofalse-positiveresults (meaning that they may say you have syphilis even if you don’t). Because of this, a positive result needs to be confirmed with a second, costlier test.
Treponemal Tests
If a non-treponemal test result is positive, one of several treponemal tests would be used to confirm the result. The tests approved for use in the United States include:
The results of a treponemal test may either be reactive (meaningT. palliumantibodies have been detected) or non-reactive (meaning thatT. pallidumantibodies were not detected).
Window Period for SyphilisThe window period is the time between when you may have been exposed to an infection and when a test can tell if you have the infection. The average syphilis window period is 21 days.If you get tested during your window period, you might end up with afalse-negative result. To be 100% sure about your results, try to wait until after the window period to get tested.
Window Period for Syphilis
The window period is the time between when you may have been exposed to an infection and when a test can tell if you have the infection. The average syphilis window period is 21 days.If you get tested during your window period, you might end up with afalse-negative result. To be 100% sure about your results, try to wait until after the window period to get tested.
The window period is the time between when you may have been exposed to an infection and when a test can tell if you have the infection. The average syphilis window period is 21 days.
If you get tested during your window period, you might end up with afalse-negative result. To be 100% sure about your results, try to wait until after the window period to get tested.
What Is the Window Period for Different STDs?
Dark-Field Microscopy
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.
How Syphilis Is Treated
Adifferential diagnosisis a process used to distinguish a particular disease (like syphilis) from others with similar features. It may involve additional tests to rule out other explanations for your symptoms.
A differential diagnosis may be especially important with syphilis given that it is sometimes referred to as the “Great Imitator.” This is not only because it mimics other diseases but also because the range of symptoms it can mimic changes with the different stages of the infection (known as primary, secondary, and tertiary syphilis).
Among the conditions commonly included in the differential diagnosis of syphilis are:
Screening Recommendations
If you think you have been exposed to syphilis, you should never consider the absence of symptoms as a reason not to get tested.
Am I at Risk of Syphilis?
Summary
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.
Frequently Asked QuestionsOnce a syphilis infection is established it takes an average of 21 days before symptoms appear. However, in some cases, it can take as little as 10 days or as many as 90 days before symptoms occur.The first symptom of syphilis is usually a single, painless skin ulcer called a chancre that develops at the site of the sexual exposure (such as in the throat or on the genitals or anus). It usually develops three weeks after exposure, although it may not be seen if it develops within the rectum or vagina.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. During the secondary phase, a rough discolored rash may develop on the palms of the hands and soles of the feet. There may also be open sores or whitish lesions in the mouth,
Once a syphilis infection is established it takes an average of 21 days before symptoms appear. However, in some cases, it can take as little as 10 days or as many as 90 days before symptoms occur.
The first symptom of syphilis is usually a single, painless skin ulcer called a chancre that develops at the site of the sexual exposure (such as in the throat or on the genitals or anus). It usually develops three weeks after exposure, although it may not be seen if it develops within the rectum or vagina.
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. During the secondary phase, a rough discolored rash may develop on the palms of the hands and soles of the feet. There may also be open sores or whitish lesions in the mouth,
10 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Ong JJ, Fu H, Smith MK, Tucker JD.Expanding syphilis testing: a scoping review of syphilis testing interventions among key populations.Expert Rev Anti Infect Ther.2018;16(5):423–32. doi:10.1080/14787210.2018.1463846Shih SL, Graseck AS, Secura GM, Peipert JF.Screening for STIs at home or in the clinic?Curr Opin Infect Dis. 2011;24(1):78–84. doi:10.1097/QCO.0b013e32834204a8Centers for Disease Control and Prevention.Syphilis—CDC fact sheet (detailed).Luo Y, Xie Y, Xiao Y.Laboratory diagnostic tools for syphilis: current status and future prospects.Front Cell Infect Microbiol. 2020;10:574806. doi:10.3389/fcimb.2020.574806Henao-Martínez AF, Johnson SC.Diagnostic tests for syphilis: new tests and new algorithms.Neurol Clin Pract. 2014;4(2):114-122. doi:10.1212/01.CPJ.0000435752.17621.48Shah D, Marfatia YS.Serological tests for syphilis.Indian J Sex Transm Dis AIDS. 2019;40(2):186-191. doi:10.4103/ijstd.IJSTD_86_19Workowski KA, Bachmann LH, Chan PA, et al.Sexually transmitted infections treatment guidelines, 2021.MMWR Recomm Rep. 2021;70(4):1-187. doi:10.15585/mmwr.rr7004a1Klausner JD.The great imitator revealed: syphilis.Top Antivir Med. 2019;27(2):71-74.Tudor ME, Al Aboud AM, Gossman M.Syphilis. In:StatPearls [Internet].Treasure Island, FL; StatPearls Publishing; 2022.Centers for Disease Control and Prevention.Screening recommendations and considerations referenced in treatment guidelines and original sources.
10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Ong JJ, Fu H, Smith MK, Tucker JD.Expanding syphilis testing: a scoping review of syphilis testing interventions among key populations.Expert Rev Anti Infect Ther.2018;16(5):423–32. doi:10.1080/14787210.2018.1463846Shih SL, Graseck AS, Secura GM, Peipert JF.Screening for STIs at home or in the clinic?Curr Opin Infect Dis. 2011;24(1):78–84. doi:10.1097/QCO.0b013e32834204a8Centers for Disease Control and Prevention.Syphilis—CDC fact sheet (detailed).Luo Y, Xie Y, Xiao Y.Laboratory diagnostic tools for syphilis: current status and future prospects.Front Cell Infect Microbiol. 2020;10:574806. doi:10.3389/fcimb.2020.574806Henao-Martínez AF, Johnson SC.Diagnostic tests for syphilis: new tests and new algorithms.Neurol Clin Pract. 2014;4(2):114-122. doi:10.1212/01.CPJ.0000435752.17621.48Shah D, Marfatia YS.Serological tests for syphilis.Indian J Sex Transm Dis AIDS. 2019;40(2):186-191. doi:10.4103/ijstd.IJSTD_86_19Workowski KA, Bachmann LH, Chan PA, et al.Sexually transmitted infections treatment guidelines, 2021.MMWR Recomm Rep. 2021;70(4):1-187. doi:10.15585/mmwr.rr7004a1Klausner JD.The great imitator revealed: syphilis.Top Antivir Med. 2019;27(2):71-74.Tudor ME, Al Aboud AM, Gossman M.Syphilis. In:StatPearls [Internet].Treasure Island, FL; StatPearls Publishing; 2022.Centers for Disease Control and Prevention.Screening recommendations and considerations referenced in treatment guidelines and original sources.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Ong JJ, Fu H, Smith MK, Tucker JD.Expanding syphilis testing: a scoping review of syphilis testing interventions among key populations.Expert Rev Anti Infect Ther.2018;16(5):423–32. doi:10.1080/14787210.2018.1463846Shih SL, Graseck AS, Secura GM, Peipert JF.Screening for STIs at home or in the clinic?Curr Opin Infect Dis. 2011;24(1):78–84. doi:10.1097/QCO.0b013e32834204a8Centers for Disease Control and Prevention.Syphilis—CDC fact sheet (detailed).Luo Y, Xie Y, Xiao Y.Laboratory diagnostic tools for syphilis: current status and future prospects.Front Cell Infect Microbiol. 2020;10:574806. doi:10.3389/fcimb.2020.574806Henao-Martínez AF, Johnson SC.Diagnostic tests for syphilis: new tests and new algorithms.Neurol Clin Pract. 2014;4(2):114-122. doi:10.1212/01.CPJ.0000435752.17621.48Shah D, Marfatia YS.Serological tests for syphilis.Indian J Sex Transm Dis AIDS. 2019;40(2):186-191. doi:10.4103/ijstd.IJSTD_86_19Workowski KA, Bachmann LH, Chan PA, et al.Sexually transmitted infections treatment guidelines, 2021.MMWR Recomm Rep. 2021;70(4):1-187. doi:10.15585/mmwr.rr7004a1Klausner JD.The great imitator revealed: syphilis.Top Antivir Med. 2019;27(2):71-74.Tudor ME, Al Aboud AM, Gossman M.Syphilis. In:StatPearls [Internet].Treasure Island, FL; StatPearls Publishing; 2022.Centers for Disease Control and Prevention.Screening recommendations and considerations referenced in treatment guidelines and original sources.
Ong JJ, Fu H, Smith MK, Tucker JD.Expanding syphilis testing: a scoping review of syphilis testing interventions among key populations.Expert Rev Anti Infect Ther.2018;16(5):423–32. doi:10.1080/14787210.2018.1463846
Shih SL, Graseck AS, Secura GM, Peipert JF.Screening for STIs at home or in the clinic?Curr Opin Infect Dis. 2011;24(1):78–84. doi:10.1097/QCO.0b013e32834204a8
Centers for Disease Control and Prevention.Syphilis—CDC fact sheet (detailed).
Luo Y, Xie Y, Xiao Y.Laboratory diagnostic tools for syphilis: current status and future prospects.Front Cell Infect Microbiol. 2020;10:574806. doi:10.3389/fcimb.2020.574806
Henao-Martínez AF, Johnson SC.Diagnostic tests for syphilis: new tests and new algorithms.Neurol Clin Pract. 2014;4(2):114-122. doi:10.1212/01.CPJ.0000435752.17621.48
Shah D, Marfatia YS.Serological tests for syphilis.Indian J Sex Transm Dis AIDS. 2019;40(2):186-191. doi:10.4103/ijstd.IJSTD_86_19
Workowski KA, Bachmann LH, Chan PA, et al.Sexually transmitted infections treatment guidelines, 2021.MMWR Recomm Rep. 2021;70(4):1-187. doi:10.15585/mmwr.rr7004a1
Klausner JD.The great imitator revealed: syphilis.Top Antivir Med. 2019;27(2):71-74.
Tudor ME, Al Aboud AM, Gossman M.Syphilis. In:StatPearls [Internet].Treasure Island, FL; StatPearls Publishing; 2022.
Centers for Disease Control and Prevention.Screening recommendations and considerations referenced in treatment guidelines and original sources.
Meet Our Medical Expert Board
Share Feedback
Was this page helpful?Thanks for your feedback!What is your feedback?OtherHelpfulReport an ErrorSubmit
Was this page helpful?
Thanks for your feedback!
What is your feedback?OtherHelpfulReport an ErrorSubmit
What is your feedback?
What is Syphilis and How is it Treated?Get Familiar With the Symptoms of SyphilisHow Syphilis Is DiagnosedHow Syphilis Is Treated
What is Syphilis and How is it Treated?
Get Familiar With the Symptoms of Syphilis
How Syphilis Is Diagnosed
By clicking “Accept All Cookies”, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts.Cookies SettingsAccept All Cookies
By clicking “Accept All Cookies”, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts.
Cookies SettingsAccept All Cookies
