What is eye syphilis?

Ocular or eye syphilis is a manifestation of syphilis, a sexually transmitted infection (STI) that can affect many parts of the body.

As the infection spreads, it can inflame and damage the eyes. It can also lead to tissue death and vision loss. However, treatment is available.

Eye syphilis is an uncommon manifestation of syphilis. It likely affects fewer than 1% of people with syphilis in the United States.

Eye syphilis occurs when a bacterium called Treponema pallidum enters a person’s body — usually through sexual contact — and causes infection. Transmission usually happens when the person with syphilis has sexual contact while they have active, transmissible sores.

As bacteria spread through the body, they can affect a wide range of functions, including the eyes.

Syphilis is not the only STI that can result in eye issues. Others include:

The symptoms of eye syphilis can emerge up to 6 months after initial contact with the bacteria.

They can appear at any stage of syphilis and vary widely, depending on the part of the eye affected and the stage at which they appear.

• sores or chancres on the eyelid or the conjunctiva, the surface of the eye
• eye pain
• lesions in the tear ducts, in some cases
• an eyelid rash
• swelling, redness, and inflammation of any part of the eye or eyelid
• nodules on the iris
• discharge
• vision changes, such as unusual spots of light and darkness or blurry vision
• vision loss
• changes in the outward appearance of the eye

Doctors divide the development of syphilis into four stages:

• stage 1
• stage 2
• latent
• stage 3

As the stages progress, bacteria spread through the bloodstream, increasing the risk of symptoms appearing throughout the body, including the eyes. Eye symptoms are most likely to occur 4–10 weeks after infection in stage 2. However, they can appear before or after this stage.

An infant born with congenital syphilis — passed on from the birthing parent — may have damage to the retina and interstitial keratitis. This is where blood vessels grow into the cornea, the clear layer at the front of the eye.

Symptoms of eye syphilis can resemble those of many other eye conditions, including pink eye or conjunctivitis. Anyone with concerns about eye symptoms should contact a doctor.

To diagnose eye syphilis, a doctor will order a complete eye exam and blood tests. Blood tests will check for signs of infection with T. pallidum bacteria and antibodies to the bacteria.

Blood tests are the only definitive way to identify eye syphilis, as many other eye conditions have similar symptoms. However, the presence of a rash or other symptoms that typically occur with syphilis can also help guide the diagnosis.

The doctor may also recommend screening for other STIs, such as HIV, as they have similar risk factors.

Eye syphilis may be difficult to detect in infants, as newborns share antibodies with their birthing parent. Experts recommend regular monitoring of newborns at risk of syphilis to detect any issues at an early stage.

Treatment for syphilis — including eye syphilis — is with antibiotics. A person may need ongoing doses of penicillin for 10–14 days.

In addition, options to help manage symptoms include:

Getting treatment for eye syphilis can also help reduce the risk of other syphilis complications.

Eye syphilis is one aspect of syphilis. People who receive early treatment for syphilis usually recover without long-term effects.

However, the disease does not go away completely but remains latent in the body. In around one-third of these cases, syphilis will then progress to the third stage.

Without treatment, around 25% of people experience a relapse at some point. In these cases, a relapse of eye symptoms can also occur.

People who do not receive treatment for syphilis will experience a wide range of health issues. They may lose their vision due to eye involvement.

Anyone with a history of syphilis or eye syphilis can help protect their health by consulting a medical professional if any concerning symptoms appear.

Here are some questions people often ask about eye or ocular syphilis.

Eye syphilis is a complication of syphilis, a bacterial infection that passes from one person to another through contact during vaginal, anal, or oral sex. It is also possible to pass it on to a newborn during delivery.

In rare cases, a person can acquire it through blood or skin-to-skin contact.

Ocular syphilis can lead to irreversible damage, but early treatment can prevent this. The longer a person waits for medical assistance, the higher the risk of irreversible damage, including vision loss.

Eye syphilis can have similar symptoms to pink eye and many other eye conditions when the external, or conjunctiva, part of the eye is involved. However, very few cases of pink eye stem from syphilis.

Who should test for an STI, and how often?

The Centers for Disease Control and Prevention (CDC) recommends testing for STIs:

• at least once for anyone ages 13–64 years
• yearly for sexually active females for gonorrhea and chlamydia if they are under 25 years or over 25 and have a change of sex partner
• from the early stages of pregnancy for syphilis and other infections that could harm a fetus
• at least once a year for syphilis and other conditions for gay, bisexual, and other men who have sex with men, and at least once every 6 months for HIV
• at least once a year for HIV for anyone whose sexual behavior or needle use increases their risk of infection
• anyone at any time if they are concerned they might have an STI

Eye or ocular syphilis is a complication of syphilis, a sexually transmitted bacterial infection. It can cause damage to a wide range of eye structures.

Eye syphilis is treatable with antibiotics. Without treatment, it can lead to irreversible eye damage and vision loss.

Anyone with concerns about eye symptoms should contact a doctor.