General paresis is an impairment of mental function caused by damage to the brain from untreated syphilis.

General paresis is one form of neurosyphilis. Today it is very rare.

The syphilis infection damages the nerves of the brain. This damage causes:

• Abnormal mental function including hallucinations and false ideas (delusions)
• Brief, sharp, "lightning" pains that occur with tabes dorsalis
• Decreased mental function
• Eye changes and abnormal pupil response
• Mood changes
• Overactive reflexes
• Personality changes
• Speech changes

General paresis usually begins about 15-20 years after the syphilis infection. Risks include syphilis infection and infection with other sexually transmitted diseases, such as gonorrhea (which may hide symptoms of syphilis infection).

Syphilis infections are passed through sexual contact with an infected person, but may also be transmitted by non-sexual contact.

• Decreased language ability (aphasia)
• Decreased motivation
• Impaired judgment
• Loss of ability to calculate
• Loss of long-term memory (long-past events)
• Loss of short-term memory (recent events)
• Muscle weakness (difficulty using legs, arms, or other parts of the body)
• Personality changes
  • Delusions, hallucinations
  • Irritability, anger
  • Inappropriate moods
  • No mood
• Seizures

Signs include:

• Change in the response of the pupil in the eye
• Inability to stand with the eyes closed (Romberg test)
• Loss of sense of vibration and position
• Muscle weakness
• Problems with walking (gait)
• Slowly worsening dementia, with loss of many brain functions

The doctor may do the following tests:

• Eye exam
• Muscle exam
• Nervous system (neurologic) exam

Blood tests to detect syphilis in the body include:

• FTA-ABS
• RPR
• VDRL

Tests of the nervous system may include:

• Cerebrospinal fluid (CSF)
• Head CT scan and MRI
• Nerve conduction tests

The goals of treatment are to cure the infection and slow the disorder from getting worse. The doctor will prescribe penicillin or other antibiotics, such as doxycycline, to treat the infection. Treatment may continue until the infection has completely cleared.

Treating the infection will reduce new nerve damage, but it will not cure damage that has already occurred. A follow-up examination of the cerebrospinal fluid is needed to see whether the antibiotic therapy worked.

Treatment of symptoms is needed for existing nervous system damage. Emergency treatment of seizures may be needed. Anticonvulsants (such as phenytoin) can help control seizures.

Patients who are unable to care for themselves may need help with such activities as eating and dressing. Those with muscle weakness may need occupational therapy or physical therapy.

Without treatment, people can become disabled. People with late syphilis infections are more likely to get other infections and diseases.

• Inability to care for yourself
• Inability to communicate or interact with others
• Injury due to seizures or falls

Call your health care provider if you have symptoms of general paresis, especially if you know you've been infected with syphilis.

Go to the emergency room or call the local emergency number (such as 911) if you have seizures.

Treating primary syphilis and secondary syphilis infections will prevent general paresis.

Practicing safe sex, such as limiting partners and using protection may reduce the risk of getting infected with syphilis. Avoid direct skin contact with patients who have secondary syphilis by wearing gloves.

Moore DP, Jefferson JW. Handbook of Medical Psychiatry. 2nd ed. St. Louis, Mo: Mosby; 2004:404-406.

Goetz, CG. Textbook of Clinical Neurology. 2nd ed. St. Louis, Mo: WB Saunders; 2003: 931-933.