A 63-year-old woman presents to the GP with her daughter. Her daughter reports a gradual deterioration of her mother's memory over the last two years, which is concerning her. During this time period, her mother has frequently been found to be talking to small children sitting by the foot of the bed, who her daughter cannot see. Over the last month, she has also noticed that her mother's movement has slowed down significantly, which is limiting her mobility, as well as a new resting tremor in her mother's hands. She has no past medical history.

Which of the following is the most likely diagnosis?

Options:
explanation: Normal pressure hydrocephalus is a cause of secondary dementia and presents with a triad of urinary incontinence, dementia, and falls. It is treatable by shunting away the excess CSF from the ventricles. This patient does not have these clinical features, but is instead presenting with the characteristic features as associated with Dementia with Lewy Bodies.
name: Normal pressure hydrocephalus
label: d
answer: no
explanation: Vascular dementia is the second commonest cause cause of dementia after Alzheimer's and presents with a step-wise decline in cognitive function due to accumulation of ischaemic infarcts over time (or small vessel disease.) Risk factors such as hypertension, hypercholesterolaemia, and diabetes should be managed. This patient has none of these risk factors, and the characteristic features are that of Lewy Body Dementia and not vascular dementia.
name: Vascular dementia
label: b
answer: no
explanation: Parkinson's Disease Dementia and Dementia with Lewy Bodies are on a spectrum with one another, presenting with similar clinical features due to a common pathophysiological basis (alpha synucleinopathy.) If the dementia precedes or begins at the same time as the movement disorder (Parkinsonism), then the diagnosis is Dementia with Lewy Bodies (also known as Lewy Body Dementia), but if the dementia occurs a year or more after the movement disorder/diagnosis of Parkinson's Disease, then the diagnosis is referred to as Parkinson's Disease Dementia.
name: Parkinson's Disease Dementia
label: e
answer: no
explanation: Alzheimer's disease is the commonest cause of dementia but does not present with movement issues or hallucinations.
Patients present with gradual loss of memory, difficulty with word-finding, poor recognition of objects and people, and an inability to carry out tasks which require fine motor function.
name: Alzheimer's disease
label: c
answer: no
explanation: Dementia with Lewy Bodies is a progressive neurodegenerative disorder caused by deposits of alpha-synuclein within the brain. Patients develop cognitive decline, hallucinations (typically of little people or animals, 'Lilliputian bodies'), and Parkinsonism. If the dementia precedes or begins at the same time as the movement disorder (Parkinsonism), then the diagnosis is Dementia with Lewy Bodies (also known as Lewy Body Dementia), but if the dementia occurs a year or more after the movement disorder/diagnosis of Parkinson's Disease, then the diagnosis is referred to as Parkinson's Disease Dementia.
name: Dementia with Lewy bodies
label: a
answer: yes

Correct answer: a