Lewy body dementia


Lewy body dementia as the name indicates is defined as the dementia with lewy bodies is a progressive, degenerative dementia of unknown etiology. Affected patients generally present with dementia preceding motor signs, particularly with visual hallucinations and episodes of reduced responsiveness and episodes of reduced responsiveness.
Dementia is the loss of mental functions severe enough to affect normal activities and relationships.
Lewy body disease happens when abnormal structures called lewy bodies, start building up in the areas of the brain. Lewy body dementia is one of the most common causes of dementia in the elderly.

Age/sex prevalence of Lewy body dementia

Lewy body disease most commonly begins between the ages of 50- 85.
Lewy body dementia occurs most commonly in men than in women.

Races affected by Lewy body dementia

Individuals of Asian, African and European races are more affected.

Causes of Lewy body dementia

The definite etiology of lewy body disease is unknown but a hypothesis is made on cause depending upon the symptoms of the disease.
Symptoms and signs probably result in part, from disruption of bidirectional information flow from the striatum to the neocortex, especially the frontal lobe.
Altered levels of neuromodulators and neurotransmitters influence the function of many neuronal circuits.
In DLB, nonpyramidal cells in layers V and VΙ of the neocortex may contain LBs.

Lewy body dementia sign and symptoms

Wide range of symptoms include the following:-
• Hallucinations
• Problems with movement and posture
• Changes in alertness and attention
• Stiffness of muscles
• Confusion of mind
• Loss of memory

Investigations of Lewy body dementia

Laboratory studies to be involved include the following:-
• Complete blood count
• Thyroid studies
• Vitamin B-12 levels
• Chemistry panel
• HIV testing
CSF examination is not required in routine tests. Patients with Alzheimer disease have higher levels of tau protein in their CSF than do patients with DLB
Patients with LB variant of Alzheimer disease have intermediate values.
CSF levels of beta amyloid are lower than normal in DLB, Alzheimer disease.
Imaging studies helpful in DLB are as follows
MRI scans show white matter lesions in patients with vascular dementia than patients with DLB.
CT scan is also helpful.
PET imaging

Treatment of Lewy body dementia

Medications to be given are as follows
• Acetylcholinesterase inhibitors are useful drugs in cases of DLB.
• Antipsychotics are given
• Antidepressents
• Benzodiazepines
• Dopamine precursors

Differential diagnosis of Lewy body dementia

• Hydrocephalus
• Lacunar syndromes
• Parkinson disease
• Parkinson-Plus syndrome
• Prion-Related diseases
• Progressive supranuclear palsy
• Cortical basal ganglionic degeneration
• Alzheimer disease
• Frontal and temporal lobe dementia

Prognosis of Lewy body dementia

DLB is a neurodegenerative disorder that results in progressive intellectual and functional deterioration. There are no known therapies to stop or slow the progression of DLB. Average survival after the time of diagnosis is similar to that in Alzheimer’s disease, about 8 years, with progressively increasing disability.