Evaluate the clinical scenarios describing older adult patients presenting with progressive cognitive or behavioral changes. Match each distinct clinical presentation with its definitive diagnostic finding or most likely underlying pathophysiological mechanism.
- A 67-year-old man is hospitalized for a 2-month history of rapidly progressing profound dementia, gait ataxia, and sudden jerky movements of his upper extremities when startled.Elevated cerebrospinal fluid 14-3-3 protein and triphasic periodic sharp wave complexes on electroencephalography.
- A 76-year-old nursing home resident develops severe lead-pipe rigidity and confusion shortly after receiving haloperidol for agitation. History includes fluctuating cognition and well-formed visual hallucinations.Widespread cortical presence of eosinophilic intracytoplasmic inclusions consisting of aggregated alpha-synuclein.
- A 59-year-old woman exhibits a 1-year history of worsening apathy, socially inappropriate comments, and a new compulsion to consume exclusively sweet foods, with relatively preserved memory.Frontal and temporal lobe atrophy associated with intracellular aggregates of hyperphosphorylated tau or TDP-43.
- A 71-year-old man exhibits a step-wise worsening of executive function over two years. Examination reveals asymmetric hyperreflexia, extensor plantar responses, and prominent emotional lability.Patchy subcortical white matter demyelination with multiple small cystic necrotic lesions in the basal ganglia.
- A 78-year-old woman presents with insidious, progressive short-term memory impairment over 3 years. She recently got lost driving in her own neighborhood but maintains appropriate social graces.Widespread cortical neuritic plaques composed of beta-amyloid peptides and neurofibrillary tangles.
Answer
Properly linking each clinical presentation to its pathophysiological mechanism requires recognizing the distinguishing features of the major neurocognitive disorders: rapid decline and myoclonus (CJD), neuroleptic sensitivity and hallucinations (DLB), personality changes (FTD), step-wise decline (Vascular), and insidious memory loss (Alzheimer).
Accurate matching requires recognizing the triad of rapid decline, ataxia, and myoclonus for CJD (14-3-3 protein, periodic sharp waves); early visual hallucinations, fluctuating cognition, and severe neuroleptic sensitivity for DLB (alpha-synuclein inclusions); early profound personality and dietary changes for FTD (Tau/TDP-43 aggregates); step-wise progression with focal signs for Vascular dementia (lacunar infarcts); and classic insidious short-term memory loss for Alzheimer disease (amyloid plaques and neurofibrillary tangles).
Step-by-Step Solution
Key Concept
Differential diagnosis and pathophysiological mechanisms of major neurocognitive disorders.