Neurosyphilis is an infection of the brain or spinal cord. It occurs in persons with untreated syphilis many years after they are first infected.

Neurosyphilis occurs about 10 to 20 years after first being infected with syphilis. It is considered a life-threatening complication of syphilis. Not everyone who has syphilis will develop this complication.

There are four different forms of neurosyphilis:

• Asymptomatic
• Meningovascular
• Tabes dorsalis
• General paresis

Asymptomatic neurosyphilis occurs before symptomatic syphilis. Signs of the disease may be seen in the spinal fluid, but the person has no symptoms.

Meningovascular neurosyphilis causes nerve and eye problems, among other symptoms. There may be damage to the blood vessels, which can lead to a stroke.

Persons with tabes dorsalis have damage to the spinal cord that slowly gets worse, making them unable to walk.

In general paresis, brain cell damage causes paralysis, tremors, seizures, and mental decline. Inflammation may occur anywhere in the brain or spinal cord and can lead to a number of neurological problems.

• Headache
• Stiff neck
• Irritability
• Poor concentration
• Mental confusion
• Depression
• Visual disturbances
• Abnormal reflexes
• Abnormal gait (walk)
• Incontinence
• Dementia
• Weakness, numbness of lower extremities
• Loss of muscle function
• Muscle contractions
• Muscle atrophy

Blood tests can be done to detect substances produced by the bacteria that causes syphilis. The oldest test is the VDRL test.

In neurosyphilis, it is important to test the spinal fluid for signs of syphilis. Tests to look for problems with the nervous system may include:

• Lumbar puncture and a CSF fluid analysis
• Cranial CT scan
• MRI scan of the brain, brainstem, or spinal cord
• Cerebral angiogram

Penicillin is used to treat neurosyphilis. The medicine may be given in various ways.

It may be injected into a vein every day for 10 days, then given into a muscle once a week for 3 weeks.

Or, your may need to take penicillin by mouth 4 times a day, combined with muscle injections -- both for 10 days -- and then taken another form of penicillin injected into a muscle for 3 weeks.

You must have follow-up blood tests at 3, 6, 12, and 24 months to make sure the infection is gone.

For information on treating syphilis, see the following articles:

• Syphilis
• Primary syphilis
• Secondary syphilis
• Tertiary syphilis

How well a person does depends on the severity of neurosyphilis before receiving treatment.

The symptoms can get slowly worse.

Call for an appointment with your health care provider if you have had syphilis in the past and now have signs of neurological problems.

Prompt diagnosis and treatment of the original syphilis infection can prevent neurosyphilis.

Mandell GL, Bennett JE, Dolin R. Principles and Practice of Infectious Diseases. 6th ed. London: Churchill Livingstone; 2005:2274-2276.

U.S. Preventive Services Task Force. Screening for Syphilis Infection: Recommendation Statement. Ann Fam Med 2004; 2: 362-365.