Lewy body and parkinsonian dementia: common, but often misdiagnosed conditions.
BACKGROUND
Dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD) are the two most common types of dementing neurodegenerative disease after Alzheimer's disease (AD). Both of these conditions are often diagnosed late or not at all.


METHODS
Selective literature review.


RESULTS
The severe cholinergic and dopaminergic deficits that are present in both DLB and PDD produce not only motor manifestations, but also cognitive deficits, mainly in the executive and visual-constructive areas, as well as psychotic manifestations such as visual hallucinations, delusions, and agitation. The intensity of these manifestations can fluctuate markedly over the course of the day, particularly in DLB. Useful tests for differential diagnosis include magnetic resonance imaging and electroencephalography; in case of clinical uncertainty, nuclear medical procedures and cerebrospinal fluid analysis can be helpful as well. Neuropathological studies have revealed progressive alpha-synuclein aggregation in affected areas of the brain. In DLB, beta-amyloid abnormalities are often seen as well.


CONCLUSIONS
DLB should be included in the differential diagnosis of early dementia. If motor manifestations arise within one year (DLB), dopaminergic treatment should be initiated. On the other hand, patients with Parkinson's disease should undergo early screening for signs of dementia so that further diagnostic and therapeutic steps can be taken in timely fashion, as indicated. Cholinesterase inhibitors are useful for the treatment of cognitive deficits and experiential/behavioral disturbances in both DLB (off-label indication) and PDD (approved indication).
Paracelsus-Elena-Klinik, Kassel, Germany. brit.mollenhauer@pk-mx.de
Brit
B
Mollenhauer
Hans
H
Förstl
Günther
G
Deuschl
Alexander
A
Storch
Wolfgang
W
Oertel
Claudia
C
Trenkwalder
D000368:Aged; D001921:Brain / Q000473:pathology; D002800:Cholinesterase Inhibitors / Q000627:therapeutic use; D003430:Cross-Sectional Studies; D003704:Dementia / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology; D003937:Diagnosis, Differential; D003952:Diagnostic Imaging; D000077265:Donepezil; D042241:Early Diagnosis; D006801:Humans; D007189:Indans / Q000009:adverse effects / Q000627:therapeutic use; D020961:Lewy Body Disease / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology; D001523:Mental Disorders / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology; D048448:Phenylcarbamates / Q000009:adverse effects / Q000627:therapeutic use; D010880:Piperidines / Q000009:adverse effects / Q000627:therapeutic use; D016032:Randomized Controlled Trials as Topic; D000068836:Rivastigmine
D002800:Cholinesterase Inhibitors; D007189:Indans; D048448:Phenylcarbamates; D010880:Piperidines; D000077265:Donepezil; D000068836:Rivastigmine