Clinical Diagnosis of Alzheimer's disease

There are several criteria for the  are:

1. Criteria for diagnosis of suspected Alzheimer's disease include:
• Dementia established by clinical examination and the mini-mental status examination or some similar examination, and confirmed with neuro psychological test
• Obtained impaired cognitive function deficits> 2
• No disturbance of consciousness level
• Onset between the ages of 40-90 years, or often> 65 years
• There is no systematic abnormalities or other brain diseases

2. Diagnosis of suspected Alzheimer's disease is supported by:
• progressive worsening of specific cognitive functions such as language, motor skills, and perceptual
• ADL disturbed and changing patterns of behavior
• A history of the family, especially if confirmed by neuropathology
• The EEG provides a description of normal or non-specific changes such as increased slow wave activity
• On a CT scan obtained cerebral atrophy

3. Another picture of the suspect diagnosis of Alzheimer's disease and other causes of dementia after being sent consists of:
• Symptoms associated with depression, insomnia, incontinentia, delusions,
• hallucinations, emotional, sexual disorders, weight loss
• other neurological disorders in some patients, particularly in the advanced stages of disease and include motor signs such as increased muscle tone, myoclonus or walking impairment
• There is a resurgence in the advanced stages

4. Description of the suspect diagnosis of Alzheimer's disease is not clear
consists of:
• sudden onset
• focal neurologic symptoms such as found hemiparese, hipoestesia, visual field deficits and impaired coordination
• There is a generation or walking impairment at the time of onset

5. Allow clinical diagnoses of Alzheimer's disease are:
• dementia syndrome, no other neurologic symptoms, psychiatric symptoms or systemic disorders that cause dementia
• The secondary systemic disorders or brain disorder that causes dementia, severe cognitive deficits gradually progressive identified no other cause

6. Criteria for a definitive diagnosis of Alzheimer's disease is a combination of clinical criteria suspects obtained an overview of Alzheimer's disease and histopathology of biopsy or autopsy.


1. Neuropathology
Itive diagnosis can not be enforced without acknowledgment neuropathology. In general atrophy obtained a bilateral, symmetrical, often ranging from 1000 g brain weight (850-1250gr). Some studies reveal atrophy more prominent in temporoparietal lobes, anterior frontal, whereas the occipital cortex, primary motor cortex, and the somatosensory system are intact.
Abnormalities in the neuropathology of Alzheimer's disease include:

a. Neurofibrillary tangles (NFT)
Neuronal cytoplasm is made of abnormal filaments containing neurofilament protein, ubiquine, epitoque. NFT is also present in the neocortex, hippocampus, amygdala, substantia alba, the locus coeruleus, the dorsal raphe nucleus of the brain stem.

NFT than found in Alzheimer's disease, are also found in the brains of elderly people, down syndrome, Parkinson's disease, SSPE, extrapyramidal syndrome, supranuclear palsy. NFT density correlated with the severity of dementia.

b. Senile plaque (SP)
Is a complex structure that occurs due to degeneration of nerve endings containing abnormal filaments, amyloid fibers extracelluler, astrocytes, microglia. Amyloid precursor protein contained in the SP is related to chromosome 21. Senile plaque is primarily found in the neocortex, amygdala, hippocampus, cortex piriformis, and little was found in the primary motor cortex, cavernosometry cortex, visual cortex, and auditory. Senile plaque is also present in peripheral tissues. Senile plaque density associated with decreased cholinergic. Second picture of histopathology (NFT and senile plaque) is a picture of the characteristics for patients with Alzheimer's disease.

c. Neuron degeneration
On microscopic examination of change and death of neurons in Alzheimer's disease is highly selective. Death of neurons in the neocortex mainly found in pyramidal neurons and frontal temporal lobe. Also found in the hippocampus, amygdala, brain stem nuclei, including the locus coeruleus, raphe nuclei and substantia nigra.

Cholinergic neuronal cell death, especially in the basal nucleus of meynert, and cells in the locus coeruleus noradrenergic primarily along the cell nucleus raphe dorsalis serotogenic, tegmentum nucleus dorsalis.

It has been found nerve growth factor on cholinergic neurons that degenerate in lesions of experimental animals, and it is the hope in the treatment of Alzheimer's disease.

d. Vacuole Changes
It is an oval-shaped neuronal cytoplasm and nucleus can shift. Number vacuole is significantly associated with the number of NFT and SP, these changes are often found in temporomedial cortex, amygdala and insular. Never found in the frontal cortex, parietal, occipital, hippocampus, cerebellum and
brain stem.

e. Lewy body
Intraneuronal cytoplasmic part that is widely available in the entorhinal, cingulate gyrus, insular cortex, and amygdala. A small amount of the cortex of the frontal, temporal, parietal, occipital. Cortical Lewy body is similar to immune reactivity that occurs in the brain stem Lewy Body on histopathologic picture of Parkinson's disease. Lewy body is, a variant of Alzheimer's disease.

2. Neuro-psychological examination

Alzheimer's disease, always cause symptoms of dementia. Function of  neuro psychological examination is to determine the presence or absence of general cognitive dysfunction and determine in detail the pattern of deficit. Psychological test also aims to assess the function displayed by some parts of the brain such as different memory impairment, loss of expression, calculation, attention and language understanding.

A systematic evaluation of neuropsychological function has Alzheimer important because:
a. The existence of Alzheim cognition associated with early dementia to know when changes that occur due to mild normal aging.
b. Comprehensive neuropsychological examination allows to distinguish cognitive abnormalities in global dementia with selective deficit caused by focal dysfunction, Alzhei Alzheimer's disease, and psychiatric disorders
c. Identify neuropsychological abnormalities caused by dementia from any cause.

The Consortium to establish a Registry for Alzheimer's Disease (CERALD) present a neuropsychological assessment procedure by using the tools batrey manifest cognitive impairment, where the examination consists of:
1. Verbal Fluency animal category
2. Modified boston naming test
3. mini mental state
4. Word list memory
5. Constructional praxis
6. Word list recall
7. Word list recognition
This test takes 30-40 minutes and <20-30 minutes on Alzheim

3. CT Scan and MRI
It is a method of high-resolution non-Alzheimer's to see the quantity of brain tissue volume changes in patients with Alzheimer antemortem. This examination is instrumental in eliminating other possible causes of dementia besides Alzheimer's such as multiinfarct and cerebral tumor. Overall cortical atrophy and ventricular enlargement are both dominant picture of a highly specific marker in this disease. But these images are also found in other dementias such as multiinfarct, Alzheimer, Binswanger so it is hard to distinguish from Alzheimer's disease.

Depletion of substantia alba and cerebral ventricular enlargement correlated with the severity of clinical symptoms and the results mini mental status examination. On MRI found an increase in the intensity of cortical areas and peri ventricular (anterior horn Capping the lateral ventricles). Capping is a predilection for early dementia. In addition to acquired abnormalities in cortical atrophy was also seen in the picture of subcortical regions such as the atrophy of the hippocampus, amygdala, and enlargement of the basal cisterns and fissures sylvii.
  MRI is more sensitive to distinguish Alzheimer's dementia from other causes, with respect to size (atrophy) of the hippocampus.

4. EEG
Useful to identify a subclinical generation activities. While in Alzheimer's disease, found slow wave changes, the frontal lobes are non-specific.

5. PET (Positron Emission Tomography)
In patients with Alzheimer's disease, PET results found decreased blood flow, O2 metabolism and cerebral glucose area. Up take I.123 greatly decreased in the parietal region, these results are highly correlated with cognitive dysfunction and always in accordance with the results of observation and neuropathology research.

6. SPECT (Single Photon Emission Computed Tomography)
Activity I. 123, the lowest in the parietal region of the Alzheimer's patients. The disorder is correlated with the level of functional impairment and cognitive deficits. Both of these checks (SPECT and PET) are not used routinely.

7. Hematology examination
No specific laboratory tests in patients with Alzheimer's. Laboratory tests only to rule out other causes of dementia such as routine blood tests, B12, Calcium, Phosphorus, BSE, renal and liver function, thyroid, folate, syphilis serology, antibody screening are selective performed.

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