Pick's disease

Definition

Pick's disease is a rare and permanent form of dementia that is similar to Alzheimer's disease, except that it tends to affect only certain areas of the brain.

Alternative Names

Semantic dementia; Dementia - semantic; Frontotemporal dementia; Arnold Pick's disease

Causes, incidence, and risk factors

People with Pick's disease have abnormal substances (called Pick bodies and Pick cells) inside nerve cells in the damaged areas of the brain.

Pick bodies and Pick cells contain an abnormal form of a protein called tau. This protein is found in all nerve cells. But some people with Pick's disease have an abnormal amount or type of this protein.

The exact cause of the abnormal form of the protein is unknown. A gene for the disease has not yet been found. Most cases of Pick's disease are not passed down through families.

Pick's disease is rare. It is more common in women than men. It can occur in people as young as 20, but usually begins between ages 40 and 60. The average age at which it begins is 54.

Symptoms

The disease can get worse slowly. Tissues in the temporal and frontal lobes of the brain start to shrink over time. Symptoms such as behavior changes, speech difficulty, and impaired thinking occur slowly, but continue to get worse.

The early personality changes can help doctors tell Pick's disease apart from Alzheimer’s. Memory loss is often the main, and earliest, symptom of Alzheimer's.

People with Pick's disease tend to behave the wrong way in different social settings. The changes in behavior continue to get worse and are often one of the most disturbing symptoms of the disease. Some patients will have difficulty with language (trouble finding or understanding words or writing).

General symptoms are listed below.

Behavioral changes:

• Can't keep a job
• Compulsive behaviors
• Inappropriate behavior
• Inability to function or interact in social or personal situations
• Problems with personal hygiene
• Repetitive behavior
• Withdrawal from social interaction

Emotional changes:

• Abrupt mood changes
• Decreased interest in daily living activities
• Failure to recognize changes in behavior
• Failure to show emotional warmth, concern, empathy, sympathy
• Inappropriate mood
• Not caring about events or environment

Language changes:

• Can't speak (mutism)
• Decreased ability to read or write
• Difficulty finding a word
• Difficulty speaking or understanding speech (aphasia)
• Repeat anything spoken to them (echolalia)
• Shrinking vocabulary
• Weak, uncoordinated speech sounds

Neurological problems:

• Increased muscle tone (rigidity)
• Memory loss that gets worse
• Movement/coordination difficulties (apraxia)
• Weakness

Other problems:

• Urinary incontinence

Signs and tests

The doctor will ask you about your medical history and symptoms.

Your health care provider might order tests to help rule out other causes of dementia, including dementia due to metabolic causes. These tests can include:

• Assessment of the mind and behavior (neuropsychological assessment)
• Brain MRI
• Electroencephalogram (EEG)
• Examination of the brain and nervous system (neurological exam)
• Examination of the fluid around the central nervous system (cerebrospinal fluid) after a lumbar puncture
• Head CT scan
• Psychological studies
• Tests of sensation, thinking and reasoning (cognitive function), and motor function

A brain biopsy is the only test that can confirm the diagnosis.

Treatment

There is no specific treatment for Pick's disease. Certain antidepressants may help manage mood swings related to Pick's disease, but further research is needed.

Sometimes patients with Pick's take the same medications used to treat other types of dementia, such as medications that decrease the breakdown of the chemical messenger, acetylcholine (anticholinesterase inhibitors), and memantine (Namenda).

In some cases, stopping or changing medications that worsen confusion or that are not essential can improve thinking and other cognitive functions. This may include medications such as:

• Analgesics
• Anticholinergics
• Central nervous system depressants
• Cimetidine
• Lidocaine

It's important to treat any disorders that contribute to confusion. These may include:

• Anemia
• Decreased oxygen (hypoxia)
• Heart failure
• Infections
• Nutritional disorders
• Thyroid disorders
• Psychiatric conditions such as depression

Treating any medical and psychiatric disorders often helps improve mental function.

Medications may be needed to control aggressive, dangerous, or agitated behaviors.

Some patients may need hearing aids, glasses, cataract surgery, or other treatments.

Behavior modification can help some people control unacceptable or dangerous behaviors. This consists of rewarding appropriate or positive behaviors and ignoring inappropriate behaviors (when it's safe to do so).

Formal psychotherapy treatment doesn't always work, because it can cause further confusion or disorientation.

Reality orientation, which reinforces environmental and other cues, may help reduce disorientation.

Depending on the symptoms and severity of the disease, the patient may need monitoring and help with personal hygiene and self-care. Eventually, there may be a need for 24-hour care and monitoring at home or in a special facility. Family counseling can help the person cope with the changes needed for home care.

Care may include:

• Adult protective services
• Community resources
• Homemakers
• Visiting nurses or aides
• Volunteer services

People may need legal advice early in the course of the disorder. Advance directives, power of attorney, and other legal actions can make it easier to make ethical decisions regarding the care of the person with Pick's disease.

Support Groups

Some communities may have support groups (such as the Alzheimer's - support group, elder care - support group, or others).

Expectations (prognosis)

The disorder quickly and steadily becomes worse. Patients become totally disabled early in the course of the disease.

Commonly, Pick's disease causes death within 2 - 10 years, usually from infection and sometimes from general failure of the body systems.

Complications

• Abuse by an over-stressed caregiver
• Infection
• Loss of ability to care for self or perform normal activities
• Loss of ability to interact with others
• Progressive loss of ability to function
• Side effects of medications used to treat the disorder
• Reduced life span

Calling your health care provider

Call your health care provider if you develop symptoms of Pick's disease.

Call your health care provider or go to the emergency room if mental function gets worse (which may mean that another disorder has developed).

Prevention

There is no known prevention.

References

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

Pearce JM. Pick's disease. J Neurol Neurosurg Psychiatry. 2003;74(2):169.

Grossman M. Frontotemporal dementia: a review. J Intl Neuropsychol Soc. 2002;8:566-583.

Grossman M. Progressive aphasic syndromes: clinical and theoretical advances. Curr Opin Neurol. 2002;15:409-413.

McKhann G, Albert M, Grossman M, Miller B, Dickson D, Trojanowski J, et al. Clinical and pathological diagnosis of frontotemporal dementia. Arch Neurol. 2001;58:1803-1809.

Goetz CG. Textbook of Clinical Neurology. 3rd ed. Philadelphia, Pa: Saunders; 2007.