Lewy body dementia and Parkinsons disease (medical students)?

Please use lay language.


Medical student needs help!

Need someone to explain in lay terms how you would differentiate pathologically/histologically and clinically between parkinson's disease and lewy body dementia.

Thank you for your help.

2 Answers

  • Mags
    Lv 7
    1 decade ago
    Favorite Answer

    Although some of the answers are readily available, this is a tricky question:

    I think your best answer is found at the Mayo Clinic in an article about the similarities and differences between the two. This article will tell you that in PDD, the lewy bodies are found in deep brain structure which control movement while in Lewy Body Dementia they are found at all structures - deep, middle and outer structures and involve emotion, behavior, judgement and awareness:


    I've made some notes but I'm not writing a paper for this answer:

    Lewy bodies = abnormal aggregates of protein which develop within degenerating nerve cells. Lewy bodies develop in regions of the brain involved in cognition and movement.


    Parkinson’s disease dementia (PDD), which accounts for at least 750,000 patients.Parkinson's Disease Dementia is also a Lewy body dementia.

    "Lewy bodies appear as spherical masses that displace other cell components. There are two morphological types: classical (brain stem) Lewy bodies and cortical Lewy bodies. A classical Lewy body is an eosinophilic cytoplasmic inclusion that consists of a dense core surrounded by a halo of 10-nm wide radiating fibrils, the primary structural component of which is alpha-synuclein. In contrast, a cortical Lewy body is less well defined and lacks the halo. Nonetheless, it is still made up of alpha-synuclein fibrils."

    source: Wikipedia



    visual hallucinations, which can be one of the first signs of the disorder. Hallucinations may range from abstract shapes or colors to conversations with deceased loved ones

    Visual hallucinations. Seeing colors, shapes, animals or people may be one of the first symptoms of Lewy body dementia.

    Movement disorders. Parkinson's-like signs may include slowed movement, rigid muscles, tremors or a shuffling walk.

    Delusions. These may consist of false ideas about another person or situation.

    Cognitive problems. Alzheimer's-like problems may include confusion, memory loss and reduced attention spans.

    Sleep difficulties causing the acting out of dreams

    Histological - ubiquitin immunohistochemistry (autopsy)

    see: diagram link below

    Clinical - correlates between sites of neutrite or lewy body pathology, neuronal loss and clinical features.

    Pathological - neuron loss associated with Lewy body & Lewy neutrite formation without other neuropathological lesions.

    Pure clinical syndromes occur when Lewy pathology is restricted to one site - when there is a mixed clinical bag with several sites incloved it becomes more complicated

    Area of Bain...............Clinical Syndrome............Name

    Nigro-striatal..............Extrapyramidal .................PD

    ................................movement disorder

    Cerebral Cortex.........Cognitive decline...............dementia

    w/cortical lewy bodies

    Sympathetic neurons..Autonomic failure..............Primary autonomic failure in spinal cord

    Dorsal vagal nuclei....Dysphagia.........................Lewy body


    Coincidental Lewy Body disorders:

    MSA (multiple systems atrophy, Progressive supranuclear palsy, Corticobasal degeneration, motor neuron disease, Hallervorfen-Spatz disease (PKAN), Neuroaxonal dystrophy, Ataxia telangiectasia. Subacute sclerosing panencephalitis, sporadic AD,

    familial AD, Down's syndrome



    source: Wikipedia:

    "Pathologically, DLB is characterized by the development of abnormal proteinaceous (alpha-synuclein) cytoplasmic inclusions, called Lewy bodies, throughout the brain. These inclusions have similar structural features to "classical" Lewy bodies seen subcortically in Parkinson's disease.

    Additionally, there is a loss of dopamine-producing neurons (in the substantia nigra) similar to that seen in Parkinson's disease, and a loss of acetylcholine-producing neurons (in the basal nucleus of Meynert and elsewhere) similar to that seen in Alzheimer's disease. Cerebral atrophy (or shrinkage) also occurs as the cerebral cortex degenerates. Autopsy series have revealed that the pathology of DLB is often concomitant with the pathology of Alzheimer's disease. That is, when Lewy body inclusions are found in the cortex, they often co-occur with Alzheimer's disease pathology found primarily in the hippocampus, including: senile plaques (deposited beta-amyloid protein), and granulovacuolar degeneration (grainy deposits within, and a clear zone around hippocampal neurons). Neurofibrillary tangles (abnormally phosphorylated tau protein) are less common in DLB"

    Age. Most cases of Lewy body dementia occur in adults older than 60.

    Sex. Lewy body dementia appears to be more common in men

    Heredity. If you have a family member with Lewy body dementia, you may be at increased risk of the disease

    Additional reading:

    http://brain.oxfordjournals.org/cgi/reprint/122/8/... from 1999 a MUST READ

    including reduced effectiveness of L-dopa and severe sensitivity reactions to neuroleptic drugs.





    although not exactly on target, skim through these:


    This is not in my target area so I'm afraid that I can't be of as much help as you need. But do the reading - it certainly raises more questions on my side of the question and answer.

    Best wishes - you still have a lot of reading and thinking.

    Source(s): references in narrative Try this search parameter: http://www.google.com/search?hl=en&rls=com.microso...
    • Commenter avatarLogin to reply the answers
  • 1 decade ago

    Parkinson's is the loss of melanin in the substantia nigra. The Lewy body dementia has Lewy bodies found in the brain at autopsy.

    Not sure about the clinical aspects, perhaps someone else can offer that information.

    • Commenter avatarLogin to reply the answers
Still have questions? Get your answers by asking now.