4. Mucous Patch
The mouth, and the genitals contain glands that are different from any other part of your body. When a person is infected by syphilis, mucous patches can appear on the genitals and the surface the mouth. Mucous patches can also appear in other areas of the body, particularly those that are exposed to heat and moisture. Secondary syphilis can lead to different changes in tissue.
This can lead to irregularities in mucus production. This mucus can clog or block the surface of your skin. The area can become inflamed and swollen when the mucus is unable to pass through the outer skin layer. Syphilis can cause this symptom, which will persist until the disease is treated.