Ocular Syphilis: A Quick Guide

Medically reviewed on July 19, 2023 by Amy Harris, MS, RN, CNM. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

Table of contents

• What Is Ocular Syphilis?
• The Connection Between Ocular Syphilis and Neurosyphilis
• Diagnosis and Treatment of Ocular Syphilis
• Ocular Syphilis Risk Factors and Prevention
• Stay Informed About Your Sexual Health
• Related Content

Syphilis is an infection that’s most often transmitted through sexual contact. However, the bacteria can also pass from a mother with syphilis to their baby (congenital syphilis) in the case of syphilis in pregnancy. [1] Typically, those with the infectious disease will experience sores or rashes around areas of sexual contact, such as the genitals and mouth.1 However, syphilis can also infect the eye and affect the nervous system in syphilis, which is an infection of any part of your eye and it can cause lasting and serious health problems for you and your baby if you are pregnant. [2]

If left untreated, ocular syphilis can lead to blindness, which is why it's critical to diagnose and treat syphilis infections as soon as possible.

What Is Ocular Syphilis?

Ocular syphilis occurs when syphilis bacteria, called Treponema pallidum, invade the eye tissues and cause ocular inflammation. It can impact several parts of the eye and manifest ocular symptoms such as [3]:

• Anterior uveitis – The uvea is your eye’s middle layer, and includes the iris (colored portion of the eye) and the ciliary body (the lower portion of the eye under the pupil). [4] Infection and inflammation of the uvea cause red eyes, eye pain, eye swelling, and inflammation. [5]
• Optic neuropathy – The optic nerve, which is found behind the eyes and carries information from your eyes to your brain, can become infected and damaged by a syphilis infection. Symptoms of a syphilis infection of your optic nerve are eye pain and vision loss. [3]
• Retinal vasculitis – This condition targets the retinal vessels, causing ocular inflammation and visual decline. [4]
• Interstitial keratitis – Enlarges the blood vessels running to and from your cornea. This condition is called interstitial keratitis and people report having tearing, eye pain, blurred vision, and increased sensitivity to bright light in one or both eyes when experiencing interstitial keratitis. [5]

That said, ocular syphilis most commonly manifests as either posterior uveitis or panuveitis. [3] The former refers to a condition which causes inflammation on the back portion of your uvea, which can also impact the retina and optic nerve. Panuveitis describes when infection The latter occurs when all parts of the uvea become inflamed, affecting the lens, retina, optic nerve, and vitreous (the gel-like fluid that fills your eye. Both of these types of ocular syphilis can cause vision impairment or blindness. [1]

You can develop ocular syphilis during any of the four stages of syphilis ( primary, secondary, and tertiary stage. [9] Ocular syphilis is most common in the second and third stages of syphilis. [6]

Primary Stage

During this first stage of the infectious disease, you may notice a hard, smooth sore called a chancre at the site of infection. People most commonly develop chancers on their genitals, mouth, or tongue (i.e. syphilis tongue), but they can show up on your eyelid as well. Chancres usually appear anywhere from 10 to 90 days after you are first infected. [1] They’re typically painless and will disappear within three to six weeks, regardless of whether or not you receive treatment with antibiotics for syphilis. [1]

You can infect your eyes with the bacteria causing syphilis if your eye or fingers come in direct contact with someone else’s infected secretions or contaminated fingers. This happens most easily when you or your partner has a chancre on the eyelid or conjunctiva (the thin clear membrane covering your eye and the white of your eye. [3,9]

Because the symptoms of primary syphilis are subtle and easily missed by healthcare providers and patients alike, ocular syphilis (more common in the later stages of syphilis) may be the first syphilis symptom picked up. [10]

Secondary Stage

If primary syphilis is left untreated, the infection will progress into the secondary syphilis stage. Rashes can appear on the skin, mouth, vagina, or anus. You can progress to the second stage even if your chancre has not yet healed, which can sometimes make diagnosis confusing. Second stage rashes are reddish-brown and rough, but they’re usually not itchy. [1]

You can also have the secondary syphilis rash on your eyelid, which may lead to blepharitis and madarosis. Conjunctivitis, episcleritis, scleritis, keratitis, and iridocyclitis can also occur during the secondary stage. [8]

Tertiary Stage

Following the secondary stage, syphilis will typically become latent, meaning there will be no signs or symptoms of the infection. Oftentimes, people will mistakenly believe that this means that the syphilis is gone. But that is not the case. Rather, without antibiotics, syphilis remains and may take years to progress into the tertiary syphilis stage, the stage with the most serious health consequences. [1] Tertiary syphilis is rare fortunately, but usually happens after someone has had untreated syphilis for 10-30 years. By this time, the infection has spread to many parts of the body such as the [1]:

• Brain
• Joints
• Nerves
• Bones
• Blood vessels
• Heart
• Liver

If you have tertiary syphilis and it has infected your eyes, you may notice a long-lasting, small, soft, tumor-like growth of tissue on your eyelid called a gumma. [9] In tertiary syphilis the infection can spread to many different parts of your eye, causing a range of eye symptoms such as [1]:

• Eye pain or redness
• Floating spots in the field of vision (“floaters”)
• Sensitivity to light and
• Changes in vision (blurry vision or even blindness)

During this stage, the infection can spread to other parts of your body, especially your brain and nervous system. This type of infection is called neurosyphilis. Unlike the primary and secondary stages, however, tertiary-stage syphilis is not infectious. [1]

The Connection Between Ocular Syphilis and Neurosyphilis

Sometimes, symptoms of ocular syphilis are associated with neurosyphilis—a syphilis infection that can impact various parts of the central nervous system, such as the brain and spinal cord. [10]

More specifically, ocular There is an overlap between neurosyphilis (infection of your nervous system) with ocular syphilis (infection of your eyes) because the two are connected by the optic nerve. Ocular syphilis can be a symptom of neurosyphilis if the infection spreads from the brain to the eye via the optic nerve. About one out of every three ocular syphilis cases also involve neurosyphilis. [1] Acute meningitis (infection and inflammation of the fluid that surrounds your brain and spinal column) is reported in 1% to 2% of patients with secondary syphilis, which can cause increased intracranial pressure, recognized by a change in your mental status and fixed pupils. [3]

Alternatively, the syphilis infection can travel down from the brain via the optic nerve, to your eye. Regardless of whether the infection started in your eye or your brain, you will likely be very sick and have some of the following signs and symptoms of a brain or spinal fluid infection such as [1, 9, 10, 12]:

• Altered mental status (confusion or loss of consciousness)
• High fevers
• Dizziness
• Weakness, loss of balance
• Nausea (feeling sick) and vomiting
• Seizures
• Stroke
• Headache
• Stiff neck

If you also have ocular syphilis with neurosyphilis, you will most likely have some, if not all of the same eye-related symptoms with tertiary syphilis [1]:

• Eye pain or redness
• Floating spots in the field of vision (“floaters”)
• Sensitivity to light and
• Changes in vision (blurry vision or even blindness)

Diagnosis and Treatment of Ocular Syphilis

All stages and forms (including ocular and neurosyphilis) of syphilis can be difficult to diagnose since symptoms can mimic other diseases and conditions. If you suspect you’ve contracted ocular syphilis, make an appointment with your healthcare provider. There is a cure for syphilis – treatment with the common antibiotic penicillin. Treatment can kill all of the bacteria, but can’t undo any damage the infection might have already done to your eyes or other parts of your body. [13]

During your in-person visit, a healthcare provider will do an eye exam to better understand your symptoms and possible causes.

They may also ask you about your sexual history, partners, history with HIV, and whether or not you’ve experienced additional syphilis symptoms. Syphilis is more common in men and people assigned male at birth (AMAB). Rates of ocular syphilis have increased in recent years, especially in gay, bisexual, men having sex with men (MSM) groups. [14,15]

Following the exam, your healthcare provider will order a diagnostic test to confirm the presence of a syphilis infection. [13] These may include the following:

• Nontreponemal diagnostic tests – The test measures the presence of any antibodies in the body, rather than those targeting the bacterium Treponema pallidum. The most widely used nontreponemal test for syphilis is the Venereal Disease Research Laboratory (VDRL) test. Another commonly used nontreponemal test is the Rapid Plasma Reagin (RPR) test. [1, 13]
• Treponemal diagnostic tests – To test for a false positive from the nontreponemal test, healthcare providers will typically follow up with this type of test to determine the specificity of the infection. It tests for antibodies that directly target the bacterium Treponema pallidum. Even those who are treated and cured will still have a positive treponemal test, meaning that it cannot decipher between past and current infections. [13]

If neurosyphilis is also believed to be present, the healthcare provider may test the cerebrospinal fluid using a CSF-VDRL (Cerebrospinal Fluid Venereal Disease Research Laboratory) test and/or a CSF-FTA-ABS (Cerebrospinal Fluid Fluorescent Treponemal Antibody Absorption). [12]

The CSF-VDRL test is typically performed as an initial screening test in suspected cases of neurosyphilis. If the CSF-VDRL is positive, indicating an active infection, further confirmation is required. The CSF-FTA-ABS test is then performed to confirm the presence of specific treponemal antibodies in the CSF. [12]

If a syphilis infection is detected, a healthcare provider will prescribe an antibiotic, such as penicillin, and, in some cases, corticosteroids or immunosuppressants to be taken alongside the antibiotic. [1,3,13]

Ocular Syphilis Risk Factors and Prevention

Being sexually active puts individuals at a higher risk of contracting ocular syphilis when infected secretions can invade the eye tissues. When participating in sexual contact with an infected individual, the transmission rates of ocular syphilis are 60%. [12]

An HIV diagnosis can also put people at a higher risk of contracting the infection: HIV patients will typically show signs of ocular syphilis before their HIV diagnosis, and HIV and syphilis infections often cluster, particularly in males who engage in sexual activity with other males. The presence of HIV may also increase the likelihood of syphilis evolving into neurosyphilis. Conversely, the presence of syphilis chancres can increase the risk of acquiring and spreading HIV. [10,15]

To reduce the likelihood of contracting syphilis or another sexually transmitted infection (STI), it’s critical to practice safe sex by always using barrier methods correctly, speaking to your partners about their sexual history, and asking your partners to get tested. If you are diagnosed with syphilis, notify your sexual partners as soon as possible so they can also get tested and receive prompt treatment if necessary. Usually, early syphilis treatment can prevent it from evolving into ocular syphilis.

Additionally, stay updated on the possible signs and symptoms of ocular syphilis since the infection can be easily mistaken for other eye conditions. You can also schedule regular eye exams with an ophthalmologist, who can identify any abnormalities or ocular manifestations, particularly if you have a history of syphilis, HIV, or another STI. [10]

See related: Can You Get Syphilis Without Having Sex?

Stay Informed About Your Sexual Health

Ocular syphilis is an evolution of the syphilis infection that can cause eye inflammation, retinal defects, and vision loss. In extreme cases, neurosyphilis can manifest, impacting vision, hearing, mood, and balance.

If you believe you’re experiencing symptoms of ocular syphilis, order an at-home Everlywell Syphilis Test. It’s discreetly shipped to your door to allow you to collect a blood sample from the comfort of your own home. The sample will be tested at a lab, and you’ll receive physician-reviewed results. If you test positive, we can connect you with a healthcare provider to discuss your online STD treatment options.

Take charge of your health with Everlywell.

Related Content

Syphilis in Pregnancy: What You Need to Know

Can You Get Syphilis Without Having Sex?

Syphilis Tongue: Here's What to Know

References

1. Syphilis, Detailed Fact Sheet. CDC. URL. Accessed June 26, 2023.
2. Congenital Syphilis. CDC. Published April 1, 2021. URL. Accessed June 16, 2023.
3. Koundanya V, Tripathy K. Syphilis Ocular Manifestations. StatPearls. Published February 22, 2023. URL. Accessed June 15, 2023.
4. Harthan J. Diagnosis and treatment of anterior uveitis: optometric management. Dovepress Clinical Optometry. doi: 10.2147/OPTO.S72079. URL. Accessed June 15, 2023.
5. Uveitis. Cleveland Clinic. URL. Accessed June 27, 2023.
6. Agarwal A, Rübsam A, Zur Bonsen L, Pichi F, Neri P, Pleyer U. A Comprehensive Update on Retinal Vasculitis: Etiologies, Manifestations and Treatments. J Clin Med. 2022;11(9):2525. Published 2022 Apr 30. doi:10.3390/jcm11092525. URL. Accessed June 12, 2023.
7. Posterior Uveitis. NORD. Published April 21, 2021. URL. Accessed June 15, 2023.
8. Panuveitis. NORDGARD. URL. Accessed June 15, 2023.
9. Ophthalmologic Manifestations of Syphilis. American Academy of Ophthalmology. Published July 30, 2022. URL. Accessed June 15, 2023.
10. Neurosyphilis, ocular syphilis, and otosyphilis. CDC. URL. Accessed June 27, 2023.
11. Neurosyphilis. National Institute of Neurological Disorders and Stroke. Published January 20, 2023. URL. Accessed June 15, 2023.
12. Meningitis. Mayo Clinic. URL. Accessed June 26, 2023.
13. STI Treatment Guidelines 2021. CDC. URL. Accessed June 27, 2023.
14. Syphilis and men who have sex with men (MSM)-CDC Fact Sheet. CDC. URL. Accessed June 26, 2023.
15. Syphilis among persons with HIV infection. CDC. URL. Accessed June 26, 2023.