Dementia with Lewy Bodies

Question 1

Outline the clinical features of DLB

Answer 1

1) Fluctuating course within seconds to days
2) Earliest deficit in attention and visuospatial domains
3) Prominent visual hallucinations
4) Axial parkinsonism rather than appendicular
5) Distinguish from PDD by onset of NCD symptoms
- DLB = NCD symptoms onset w/parkinsonism onset
- PDD = NCD symptoms onset >1y after parkinsonism onset
4) Association w/repeated falls + syncope + ANS dysfunction + sleep disorders

Question 2

Outline the genes involved in DLB

Answer 2

1) Mutations in α-synuclein
- α-synuclein mutations causes formation of Lewy bodies
- DLB occurs later in the 70s as Lewy body load is lower
- PDD occurs earlier in the 50s as Lewy body load is higher

Question 3

Outline the pathology seen in DLB

Answer 3

1) Lewy bodies composed of α-synuclein and ubiquitin
2) In paralimbic and neocortical regions
3) In basal ganlia as well for PDD

Question 4

Explain why antipsychotics are contraindicated in DLB

Answer 4

1) Antipsychotics are dopamine antagonists
2) DLB and PDD are already in a state of dopamine deficiency
3) Further reduction in dopamine worsens parkinsonism
4) May precipitate neuroleptic malignant syndrome
- triad of fever + muscle rigidity + ANS dysfunction