What happens to untreated primary syphilis?

In untreated primary syphilis, the infection does not just remain static; instead, it can progress to later stages if left without intervention. Primary syphilis is characterized by the presence of a painless sore, known as a chancre, at the site of infection. If this initial stage is not treated, the bacteria causing syphilis can multiply and spread throughout the body, leading to secondary syphilis, which presents with more systemic symptoms such as rashes, fever, and swollen lymph nodes. This progression underscores the importance of early detection and treatment of syphilis to prevent complications that arise from the subsequent stages of the disease.

The other outcomes, such as resolving spontaneously, remaining the same indefinitely, or disappearing completely, do not accurately depict the behavior of untreated primary syphilis. Without treatment, the Treponema pallidum bacteria remain active in the body, thus triggering potential complications with progression through the stages of the disease.