Testing and Diagnosis
Syphilis is commonly called the "great imitator", because it imitates many other diseases. So, it can be difficult to diagnose syphilis. Only a doctor or a health care professional can diagnose syphilis. Persons who have been diagnosed with other sexually transmitted diseases, such as chlamydia or gonorrhea, should be tested for syphilis.
A doctor usually will notice the signs or symptoms of syphilis. A doctor can also test a sample from a sore or chancre.
A blood test is also done to test for the disease. In cases where advanced syphilis is suspected, a spinal tab (lumbar puncture) might be done to find out if syphilis has affected the nervous system.