Pick's Dementia
Dementia is a loss of cognitive (mental) abilities that occur mostly with advancing age, cases have been picked up also in the relatively young.
Alzheimer's disease is the most common cause of dementia. However, there are other types of dementia as well. Individuals with Alzheimer's disease usually have memory loss as their most prominent symptom. Problems with language, sense of direction, mood and behaviour occur, but are less prominent in the early stages of the disease. This is because in Alzheimer's disease the memory areas of the brain are particularly susceptible to the disease process. When the most prominent symptom is not memory loss, the physician may suspect other types of dementia. Early symptoms that suggest the diagnosis of Pick's disease include progressive language dysfunction, emotional changes including lability, apathy, euphoria or depression. Personality change, impaired judgement and insight, impulsive behaviour, restlessness or fatigue also occur. Criminal behaviour in an individual who had previously been honest also raises the possibility of Pick's disease. These symptoms occur because the frontal and temporal lobes of the brain are susceptible in Pick's disease. These lobes are important for language skills, impulse control, energy and enthusiasm, problem solving and for maintaining socially appropriate behaviour.
Neuroimaging studies including computerized tomography (CT or CAT scans) and magnetic resonance imaging studies (MRIs) of the brain can support the diagnosis of Pick's disease. The first figure above is a CT scan of the brain from a patient with Pick's disease. Here, atrophy (shrinkage) of the frontal and temporal regions (front half of the brain) is seen. In this image the skull is the white outer band; the brain (inside the skull) is gray; the cerebrospinal fluid (CSF) spaces are the dark regions in the middle of the brain and between the brain and the skull. In Pick's disease the front (top, in the image above) of the brain atrophies (gets smaller) and the CSF spaces become larger. The back parts of the brain (occipital regions) remain normal.
PET or SPECT studies which measure brain metabolism and blood flow may also support the diagnosis of Pick's disease.
Although affected brain regions often contain Pick bodies, some patients with symptoms of frontotemporal dementia do not have Pick bodies. At this time we don't know the relationship between frontotemporal dementia cases with Pick bodies and those lacking them. Since there is no definite way during life to determine which frontotemporal lobe dementia patients have Pick bodies and which ones do not, many physicians will use the term's frontotemporal dementia and Pick's disease interchangeably.
The second photograph above is a microscopic image of brain tissue from a person who died after six years of progressive personality change, restlessness and disinhibited behavior. The Pick bodies are the rounded brown spots inside the brain cells (neurons). Pick bodies are composed of abnormal forms of a protein called tau. Here, a stain that is specific for the protein tau colors the Pick bodies brown. There are five Pick bodies in this image.
Biochemical studies show that there are six different forms of the tau protein in the normal human brain. In normal brains the ratio of the shorter forms of tau to the longer ones is 1:1. In Pick's disease the ratios of the tau forms are not normal - there are more of the short tau proteins than the long ones.
There is currently no cure for Pick's disease. However, there are medications and behavioral strategies that may be useful for management of the symptoms of Pick's disease. Last spring the South East Pennsylvania Alzheimer's Association sponsored a 2-day multidisciplinary meeting on Pick's disease and frontotemporal dementia. We have a support group for Pick's disease where interested individuals may learn more about the disease and about management of the symptoms these patients experience.
Information source: Philladelphia USA
http://www.alz-sepa.org/pageoflinks/
Pick's Disease is well know in the United Kingdom and there are many support groups
Click on the link below for further details
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