Differential Diagnosis
- Single most likely diagnosis
- A) Dementia, Lewy body: This diagnosis is the most likely due to the combination of cognitive decline (personality changes, slow to answer), visual hallucinations (seeing people that are not actually present), and motor symptoms (rigidity, slowed gait). These symptoms are characteristic of Dementia with Lewy bodies, which often presents with fluctuations in cognitive function, visual hallucinations, and parkinsonian motor symptoms.
- Other Likely diagnoses
- B) Frontotemporal dementia: Although less likely, frontotemporal dementia could be considered due to the personality changes and cognitive decline. However, the presence of visual hallucinations and parkinsonian symptoms (rigidity) makes Dementia with Lewy bodies more likely.
- D) Progressive supranuclear palsy: This diagnosis could be considered due to the presence of falls and rigidity. However, the hallmark symptom of progressive supranuclear palsy is difficulty with vertical eye movements, which is not noted in this patient.
- Do Not Miss diagnoses
- C) Huntington disease: Although less likely due to the age of onset and lack of reported family history, Huntington disease can present with cognitive decline, personality changes, and motor symptoms (chorea, not rigidity). It is essential to consider this diagnosis due to its significant implications for the patient and their family.
- Rare diagnoses
- E) Tardive dyskinesia: This diagnosis is unlikely as it typically presents with involuntary, repetitive body movements, which are not described in this patient. Tardive dyskinesia is often associated with long-term use of antipsychotic medications, which is not mentioned in the scenario.