Paresis: Definition, Causes, Symptoms, Diagnosis, Treatment and Prevention

Also known as general paralysis of dementia, it is a neuropsychiatric disorder of rare occurrence at present.

Paresis, which affects the brain and central nervous system, is caused by syphilis.

It had been considered a psychiatric disorder before and during the 19th century when it was first identified scientifically and discovered to be extremely common.

It is a condition that occurs when a syphilitic infection, untreated, causes a gradual loss of cortical function of the brain, which causes progressive dementia to reach a general paralysis.

It is also called Bayle’s disease or paralytic dementia.


General paresis develops as neurosyphilis.

It usually occurs in patients who have had syphilis and were not appropriately treated.


Syphilis is a disease caused by a bacterial infection, most often transmitted through sexual contact.

Today, neurosyphilis is a sporadic disease.

When the patient presents neurosyphilis, the bacteria that cause syphilis attack the brain and nervous system.

The patient begins to suffer from general paresis 10 to 30 years after having contracted the infection by syphilis.


Syphilis infection can damage many different nerves of the brain.

With general paresis, the symptoms are usually similar to those of dementia and may include:

  • Memory problems, both long-term (past events) and short-term (recent events).
  • Language problems, such as saying or miswriting words ( aphasia ).
  • Decreased mental function, such as problems thinking and altering the judgment.
  • Constant changes of humor.
  • Changes in personality such as delusions, hallucinations, irritability, anger, bad moods, and inappropriate behavior.
  • Decreased motivation
  • Loss of ability to calculate.
  • Muscle weakness (difficulty using legs, arms, or other body parts).
  • Convulsions

The signs include:

  • Change in the response of the pupil in the eye.
  • The irregular shape of the pupil.
  • Inability to stand with closed eyes (Romberg test).
  • Loss of sense of vibration and position.
  • Problems are walking (walking).

Dementia slowly gets worse with the loss of many brain functions.

Possible complications

The complications that this syndrome presents:

  • The inability to interact or communicate with others.
  • An injury caused by a seizure or fall.
  • They can cause permanent disability.


The diagnosis can be differentiated from other known psychoses by a characteristic abnormality in the reflexes of the pupil of the eye.

Eventually, the development of muscle reflex abnormalities, seizures, deterioration of memory (dementia), and other signs of relatively widespread neurocerebral corruption.

The doctor will perform a physical examination and a medical history. Tests must be performed to verify the functioning of mental function.

Tests that can be ordered to detect syphilis in the body include:

Lab tests:

  • Laboratory tests of cerebrospinal fluid: To detect the presence of syphilis in the spinal cord. Affectation of the brain and spinal cord is often a sign of late-stage syphilis (CSF-VDRL).
  • Absorption test fluorescent treponemal antibodies: It is a test in the blood used to detect antibodies against the bacteria Treponema pallidum, which is responsible for causing syphilis (FTA-ABS).
  • Blood and urine tests to detect syphilis: The rapid plasma reagin test (RPR) and the laboratory test to diagnose venereal diseases (VDRL) to detect syphilis and venereal diseases in the blood.

Nervous system tests:

  • Computed tomography of the head and magnetic resonance imaging.
  • Nerve conduction tests evaluate the speed with which the impulses travel through the nerves.
  • Vision test.
  • Muscle exam.


The treatment consists of mainly curing the infection and, therefore, delaying the development of this syndrome.

Penicillin therapy and other antibiotics are used to treat the infection.

The treatment against the infection will last until the condition disappears completely. Also, it will avoid damage to the new nerves.

However, it will never be able to cure the damage that has already occurred.

The treatment also includes a follow-up examination of the cerebrospinal fluid to see if antibiotic therapy is working.

Seizures rarely occur, but emergency treatment may be necessary if they occur.

Anticonvulsant medications can help control seizures.

Patients who can not care for themselves may need help with activities such as eating and dressing.

Those with muscle weakness may need occupational therapy or physiotherapy.


If treatment is not administered, patients may become disabled.

In addition, late syphilis infections can cause patients to be more likely to contract other types of conditions and diseases.


The treatment of primary syphilis and secondary infections due to syphilis prevents general paresis.

On the other hand, safe sex, with the use of protection (condoms), limiting the number of couples, and avoiding direct contact with people suffering from syphilis, prevents infection and, therefore, the development of the disease.