What Happens If Syphilis Is Left Untreated?

Syphilis is a bacterial infection caused by Treponema pallidum. Syphilis is a sexually transmitted disease (STD). Syphilis can also be transmitted from the mother to unborn baby. Occasionally, the bacteria can enter your body through minor cuts or abrasions on the skin or mucous membranes. Syphilis is contagious during its primary and secondary stages and rarely in the early periods of the tertiary (latent) stage. After the initial infection, the bacteria may remain inactive (dormant) in the body many years, even decades before becoming active. Syphilis can be completely cured in the initial stages. Without treatment, syphilis can lead to life-threatening complications and permanently damage the heart, brain, and other organs.

The following factors increase the risk of acquiring syphilis:

• Unprotected sexual intercourse 
• Multiple sexual partners
• Men having sex with men (MSM)
• Human immunodeficiency virus/Acquired immunodeficiency virus (HIV/AIDS) infection 

Syphilis progresses in stages, and the presentation varies at each stage. The signs and symptoms of syphilis at every stage of syphilis are as follows:

• Primary syphilis: Syphilis begins with a small, shallow, painless sore, also called a chancre, around three weeks after exposure. The sore can occur anywhere over the body but is common in the mouth and genitals. It may sometimes be hidden within the rectum or vagina. Most patients usually develop only one chancre, and some people develop many. Chancres usually heal on their own six weeks.
• Secondary syphilis: Few weeks after the chancre heals, a rash appears, starting on the trunk and spreads to the rest of the body including the palms and soles. There is usually no pain or itching. Wart-like sores can occur in the mouth or genitals. Patients also have hair loss, muscle pain, fever, throat pain, and enlarged lymph nodes. These signs and symptoms may disappear after a few weeks or may appear on and off up to a year.
• Latent syphilis: If patients are not treated for syphilis, the disease enters the latent (hidden) stage. During the latent stage, patients usually do not have any symptoms, and this can last for many years. Signs and symptoms may never return, or the disease can progress to the tertiary stage.
• Tertiary syphilis: Tertiary syphilis is also known as the late stage of syphilis. Around 15-30% of patients that go untreated develop complications of syphilis called tertiary syphilis. The disease may permanently damage the brain, nerves, eyes, heart, blood vessels, liver, bones, and joints that can be life threatening. These complications can occur years after the initial untreated infection.
• Neurosyphilis: This can occur at any stage. The infection can spread and cause damage to the brain and nerves.
• Congenital syphilis: Syphilis can also be transmitted from the mother to unborn baby or at the time of birth. Most newborns with congenital syphilis may not have any symptoms initially. Some babies have a rash on the palms and soles. Signs and symptoms that may develop later include deafness, teeth deformities, and saddle nose deformity (collapsed nose). Babies with syphilis may also be born prematurely, be born dead, or die soon after birth.