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

General paresis is one form of neurosyphilis. It is a complication of a late, untreated syphilis infection. General paresis is a progressive, life-threatening complication.

The syphilis infection causes widespread damage to the nerves of the brain. This damage results in personality changes, mood changes, hyperactive reflexes, eye changes with abnormal pupil response, abnormal mental function including hallucinations and delusions, decreased intellectual functioning, speech changes, and brief, sharp, "lightning" pains that are characteristic of tabes dorsalis.

General paresis typically begins about 15-20 years after the original syphilis infection. The risks include previous syphilis infection and previous infection with other sexually transmitted diseases, such as gonorrhea (which may hide symptoms of syphilis infection). Syphilis infections are transmitted primarily through sexual contact with an infected lesion, but may also occasionally be transmitted by non-sexual contact.

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

An eye examination may indicate a change in pupil response. A neurologic and muscular examination indicates slowly progressive dementia, with loss of multiple brain functions. Muscle weakness may be evident. There may be a loss of vibratory and position sense. Gait disturbances are common. The person may be unable to stand with the eyes closed (Romberg test).

Blood tests to detect syphilis in the body include:

• VDRL
• FTA-ABS
• RPR

• CSF (cerebrospinal fluid) 
• Head CT scan
• Nerve conduction tests

The goals of treatment are to cure the infection and reduce progression of the disorder. Treatment of the infection will reduce new nerve damage, but will not cure existing damage. Penicillin or other antibiotics, such as doxycycline, are given to treat the infection. Treatment may be prolonged to ensure that the infection is completely cleared. A follow-up examination of the cerebrospinal fluid is required to evaluate the effectiveness of antibiotic therapy.

Symptomatic treatment is required for existing neurologic damage. Emergency treatment of seizures may be required. Anticonvulsants (such as phenytoin) may be needed to control seizures.

Assistance or supervision with such activities as eating and dressing may be needed if patients are unable to care for themselves. Physical therapy, occupational therapy, or other interventions may be appropriate for people with muscle weakness.

Progressive disability is likely. People with late syphilis infections are more prone to the development of other infections and diseases. If not treated, progressive disability is likely.

Complications include the inability to care for oneself, the inability to communicate or interact, injury caused during seizures, and injury from falls (related to unsteady gait).

Call your health care provider if the symptoms of general paresis are present, particularly if there is a known history of syphilis infection.

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

Adequate treatment and follow-up of primary syphilis and secondary syphilis infections will prevent general paresis.

Safer sex practices, such as limiting partners and using protective barriers when in contact with potentially infectious material, may reduce the risk of developing the initial syphilis infection.

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.