What is the worst case of syphilis?

Tertiary, a late symptomatic stage of syphilis, is currently a rare complication of untreated syphilis due to the advent of penicillin. It typically occurs between 10–30 years following the initial infection.

Medical professionals associate tertiary syphilis with damage to several organ systems and potentially death. Affected systems can include:

• joints
• brain
• eyes
• nerves
• bones
• heart
• liver
• blood vessels

A person can prevent tertiary syphilis through screening for the infection if they have a higher risk of developing it. People at higher risk who can consider getting tested regularly include the following populations:

• bisexual or gay males
• those living with HIV
• partners of those who tested positive for syphilis
• those taking preexposure prophylaxis (PrEP) for HIV prevention
• people who are pregnant who may have been exposed to syphilis

Since tertiary syphilis can affect many different organs and body systems, the symptoms can vary based on what organs it affects.

Some possible symptoms include:

• difficulty moving arms and legs
• numbness
• paralysis
• heart disease
• blindness

At any stage of infection, syphilis can enter different parts of the body, including:

• visual system (ocular syphilis)
• nervous system (neurosyphilis)
• auditory or vestibular system (otosyphilis)

These can cause a range of symptoms, which can include:

• severe headache
• muscle weakness
• trouble with muscle movements
• changes to mental state, such as trouble focusing, confusion, or personality change
• dementia, such as problems with memory, thinking, or decision making
• changes in vision or blindness
• eye pain
• redness in the eye
• ringing, hissing, buzzing, or roaring in the ears
• hearing loss
• dizziness or vertigo

Since the use of penicillin as a treatment option, tertiary syphilis occurrences have dropped. However, it can still occur if early stage syphilis goes unrecognized or untreated.

The rate of syphilis infections per year has increased in the United States. According to data from the Centers for Disease Control and Prevention (CDC), there were 207,255 cases of syphilis in 2022. This was an increase of 17.3% between 2021 and 2022. Of these numbers, 59,016 were primary and secondary stage syphilis, the most infectious types.

Identification and treatment of syphilis can help cure a person of the infection and prevent tertiary syphilis from occurring.

Treatment for tertiary syphilis typically involves three doses of intramuscular benzathine penicillin G. People typically spread the doses out over 3 weeks with one dose per week. However, some manifestations of syphilis may require IV penicillin.

For people who cannot take penicillin due to allergy or other reasons, the recommended treatment is oral doxycycline 100 milligrams (mg) twice daily for 30 days. Another option is Ceftriaxone IM, a once-daily injection for 10–14 days.

While treatment can stop the infection and kill the bacteria, it may not reverse any damage syphilis causes.

A person may discuss treatment options with a healthcare professional before starting antibiotics. A person can also inform the healthcare professional if they do not tolerate penicillin.

Following treatment, a person can develop syphilis again. To help prevent infection, a person can take steps such as:

• using condoms or other barrier methods during intercourse
• only having sexual relations with one person or people who do not have the infection
• getting yearly blood tests

Untreated syphilis can stay in a person’s body for the rest of their lives. It can cause organ damage, tissue damage, and potentially death. Symptoms and signs of damage may not present for many years.

A person may also pass syphilis on to any of their sexual partners.

In some cases, it can enter a latent stage. During this stage, a person will not present with any symptoms, but a blood test can show the infection.

In rare cases, it can enter tertiary syphilis.

The following sections provide answers to some frequently asked questions about syphilis.

Penicillin or other antibiotics can cure syphilis. However, treatment may not undo the damage that syphilis causes to the body.

Syphilis breaks down into four stages, including:

• Primary stage: This is the initial infection, which medical professionals associate with a painless, swollen bump at or near the site where syphilis entered the body. It will heal on its own regardless of treatment.
• Secondary stage: This stage may include different symptoms, such as fatigue, fever, or sore throat, along with a rough rash appearing shortly after the original sore healed.
• Latent stage: The bacteria can remain dormant in the body for several years.
• Tertiary stage: This is a rare occurrence due to untreated syphilis, associated with severe organ damage and possible death.

Syphilis may enter a late stage if not treated in one of the earlier stages. Treatment with antibiotics can cure the infection and prevent tertiary syphilis from occurring.

If it occurs, it can lead to damage to several organ systems and possible death.

A person at risk of syphilis can get tested regularly for infection. If an infection is present, a healthcare professional can treat the infection with antibiotics.