Lewy Body Dementia(DLB)
Dementia with Lewy Bodies (DLB) is a neurodegenerative disorder characterized by the association of progressive cognitive deficits with fluctuations in attention, visual hallucinations, and parkinsonian signs. It is classified as one of the synucleinopathies, along with Parkinson’s disease and multiple system atrophy.
DLB is caused by the abnormal accumulation of alpha-synuclein in the form of Lewy bodies within cortical and subcortical regions. Genetic factors (such as variants in GBA1 and APOE ε4) and environmental factors contribute to its onset, although most cases are sporadic.
DLB is defined by a combination of symptoms:
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Marked cognitive fluctuations throughout the day.
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Well-structured visual hallucinations.
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Parkinsonism, often mild and symmetrical.
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REM Sleep Behavior Disorder (RBD).
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Marked sensitivity to antipsychotics.
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Autonomic dysfunctions (hypotension, constipation).
Cognitive impairment primarily affects attention, executive functions, and visuospatial abilities.
Diagnosis is based on the international criteria of the DLB Consortium. MRI may be normal or show mild cortical atrophy. Dopaminergic SPECT or PET scans reveal reduced uptake in the basal ganglia. Amyloid PET imaging and cerebrospinal fluid (CSF) markers can be useful in distinguishing DLB from Alzheimer’s disease.
Available therapies
Treatment includes:
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Cholinesterase inhibitors for cognitive symptoms.
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Low-dose dopaminergic drugs for parkinsonism, used with caution due to the risk of confusion.
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Melatonin and clonazepam for REM sleep behavior disorder.
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Multidisciplinary management of autonomic disorders.
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The use of antipsychotics must be minimized and limited to strictly necessary cases.
Research in progress
- Research is investigating new synuclein biomarkers, anti-alpha-synuclein therapies, and iPSC-derived cellular models. Diagnostic techniques based on misfolded protein amplification (RT-QuIC) are currently under development.
Reference laboratory
Contacts and informations
Dott. Alessio Di Fonzo
Mail: alessio.difonzo@policlinico.mi.it
Segreteria: elena.oriani@policlinico.mi.it