If your doctor suspects that you have syphilis, he or she will look for any of the typical symptoms of the disease, especially for a chancre in the genital area. Your doctor can diagnose syphilis by taking a sample of fluid from a suspicious ulcer and having that fluid examined under a microscope for the presence of syphilis bacteria.
Your doctor also may order blood tests to check for certain antibodies that are present in people with syphilis. However, in some cases, people without syphilis test positive for these antibodies. A positive test may have to be confirmed with a second blood test.
Because of the high risk of HIV infection in people with syphilis, public health officials say that all people infected with syphilis should be tested for HIV infection.
Unless treated, syphilis is a lifelong illness.