Dementia

Question 1

A patient with early personality changes and behavioral symptoms is diagnosed with a neurodegenerative disorder formerly called Pick disease. What is the characteristic histopathological finding?”

Answer 1

Pick bodies (hyperphosphorylated tau)

Question 2

A 55-year-old male exhibits inappropriate social behavior, impulsivity, and compulsive eating. MRI shows frontal and temporal lobe atrophy.

Answer 2

Frontotemporal dementia

Question 4

A patient with FTD symptoms also has bradykinesia and rigidity. What is the underlying pathology?

Answer 4

Degeneration of the basal ganglia

Question 5

MRI show of FTD ?

Answer 5

MRI shows prominent frontal and temporal atrophy.

Question 6

Autopsy of a dementia patient shows round eosinophilic inclusions of hyperphosphorylated tau in the neurons of the frontal and temporal lobes

Answer 6

Pick bodies -FTD

Question 7

A 70-year-old man reports seeing small animals in his room that aren’t there. Which dementia ?

Answer 7

Lewy bodies D - HaLewycinations

Question 8

Clinical features of LBD ?

Answer 8

Fluctuating cognition (good & bad days)
REM sleep behavior disorder (acting out dreams)
Mild Parkinsonism (bradykinesia, tremor, rigidity)

Question 9

An elderly man presents with fluctuating alertness, vivid hallucinations, and mild parkinsonian features. What is the most likely diagnosis?

Answer 9

LBD

Question 10

A biopsy shows eosinophilic cytoplasmic inclusions in neurons that contain α-synuclein.

Answer 10

Lewy bodies

Question 11

Dementia + Parkinsonism - Dx ?

Answer 11

If dementia + Parkinsonism appear together, the timeline is crucial!

If cognitive symptoms appear first → Lewy Body Dementia

If Parkinson’s symptoms appear first (>1 year before dementia) → Parkinson’s Disease Dementia

Question 12

USMLE often asks about the most common causes of dementia:

Answer 12

Alzheimer’s Disease (most common)
Vascular Dementia (second most common)

Question 13

Vascular dementia pathology ?

Answer 13

Small vessel disease (lacunar strokes) and multiple infarcts → cause cumulative damage to cognition

Question 14

A 75-year-old man with a history of hypertension and multiple strokes presents with a progressively worsening cognitive function in a stepwise pattern.

Answer 14

Vascular dementia

Question 15

CT scan of the brain shows multiple infarcts in the cortical and subcortical areas. What is the likely cause of the patient’s cognitive impairment?”

Answer 15

Vascular dementia

Question 16

A patient develops rapidly progressive dementia, myoclonus, and ataxia over 2 months

Answer 16

CJD

Question 17

Histology shows spongiform changes in the brain without inflammatory response.

Answer 17

Cjd

Question 18

Diagnostic clues USMLE loves to test for Cjd ?

Answer 18

EEG: Periodic sharp waves
CSF: ↑ 14-3-3 protein

Question 19

Transmitted by Cjd ?

Answer 19

Corneal transplantation
Neurosurgical equipment

Question 20

Pathology of CJD ?

Answer 20

Conversion of normal prion protein (PrPᶜ) to abnormal PrPˢᶜ → Spongiform encephalopathy

Question 21

A 40-year-old HIV-positive patient develops memory loss, impaired concentration, and gait disturbances.”

Answer 21

HIV-associated dementia

Question 22

Brain biopsy shows microglial nodules and multinucleated giant cells in the subcortical white matter.

Answer 22

HIV - D

Question 23

A 55-year-old man exhibits inappropriate social behavior, compulsive eating, and apathy. MRI shows frontal and temporal lobe atrophy. What histopathological finding is most likely?
A. Hyperphosphorylated tau inclusions
B. β-amyloid plaques
C. Spongiform vacuolation
D. Lewy bodies

Answer 23

A

Question 24

A patient with progressive nonfluent aphasia is found to have neuronal inclusions positive for ubiquitinated TDP-43. Which dementia is most likely?
A. Alzheimer’s disease
B. Frontotemporal dementia
C. Vascular dementia
D. Creutzfeldt-Jakob disease

Answer 24

B

Question 25

A 60-year-old man presents with early disinhibition and compulsive behavior. He has no memory loss but engages in repetitive hand clapping and hoarding objects. What is the most likely diagnosis? A. Lewy body dementia B. Frontotemporal dementia C. Alzheimer’s disease D. Vascular dementia

Answer 25

B

Question 26

A 72-year-old man reports seeing small animals in his room. He also has fluctuating cognition and REM sleep behavior disorder. What is the most likely diagnosis? A. Parkinson’s disease dementia B. Lewy body dementia C. Alzheimer’s disease D. Creutzfeldt-Jakob disease

Answer 26

B

Question 27

A patient with parkinsonian features and cognitive decline within 6 months has a brain biopsy showing eosinophilic cytoplasmic inclusions of α-synuclein in the cortex. What is the most likely diagnosis? A. Parkinson’s disease dementia B. Lewy body dementia C. Vascular dementia D. Creutzfeldt-Jakob disease

Answer 27

B

Question 28

A 74-year-old patient presents with visual hallucinations, parkinsonism, and fluctuating cognition. What is the histological hallmark? A. Lewy bodies in the cortex B. Neurofibrillary tangles C. Pick bodies D. Prion plaques

Answer 28

A

Question 29

A 70-year-old man with a history of hypertension, diabetes, and multiple strokes presents with stepwise cognitive decline. What is the most likely cause? A. Alzheimer’s disease B. Vascular dementia C. Frontotemporal dementia D. Lewy body dementia

Answer 29

B

Question 30

A 75-year-old man presents with late-onset memory impairment and executive dysfunction. MRI shows multiple infarcts in the subcortical white matter. What is the diagnosis? A. Alzheimer’s disease B. Vascular dementia C. Lewy body dementia D. Creutzfeldt-Jakob disease

Answer 30

B

Question 31

What is the most important risk factor for vascular dementia? A. Smoking B. Hypertension C. Alcohol use D. Family history of dementia

Answer 31

B

Question 32

A patient with rapidly progressive dementia, myoclonus, and ataxia is found to have a spongiform cortex. What is the underlying pathology? A. Hyperphosphorylated tau B. Prion disease (PrPᶜ → PrPˢᶜ) C. β-amyloid plaques D. Lewy bodies

Answer 32

B

Question 33

A patient develops rapidly progressive dementia over 2 months. EEG shows periodic sharp wave complexes. What CSF finding would confirm the diagnosis? A. Increased 14-3-3 protein B. Decreased Aβ42 C. Increased total tau D. Elevated α-synuclein

Answer 33

A

Question 34

What is the most common mode of transmission for Creutzfeldt-Jakob disease? A. Blood transfusion B. Ingestion of contaminated meat C. Sporadic mutation D. Corneal transplant

Answer 34

D

Question 35

A 42-year-old HIV-positive man has progressive cognitive decline, mood disturbances, and gait instability. What is the most likely cause? A. Progressive multifocal leukoencephalopathy (PML) B. HIV-associated dementia C. Neurosyphilis D. Cryptococcal meningitis

Answer 35

B

Question 36

What neuropathological feature is most characteristic of HIV-associated dementia? A. Pick bodies B. Neurofibrillary tangles C. Microglial nodules with multinucleated giant cells D. Lewy bodies

Answer 36

C

Question 37

A patient with advanced HIV has MRI findings showing diffuse gray matter atrophy. What is the likely diagnosis? A. Creutzfeldt-Jakob disease B. HIV-associated dementia C. Alzheimer’s disease D. Subacute sclerosing panencephalitis

Answer 37

B

Question 38

A 60-year-old man presents with progressive memory loss over 5 years. His MRI shows diffuse cortical atrophy, particularly in the hippocampus. What is the most likely diagnosis? A. Alzheimer’s disease B. Frontotemporal dementia C. Vascular dementia D. Creutzfeldt-Jakob disease

Answer 38

A

Question 39

A 78-year-old man has urinary incontinence, gait disturbance, and cognitive impairment. MRI shows ventriculomegaly with normal sulci. What is the diagnosis? A. Alzheimer’s disease B. Normal pressure hydrocephalus C. Creutzfeldt-Jakob disease D. Lewy body dementia

Answer 39

B

Question 40

What is the most specific EEG finding in Creutzfeldt-Jakob disease? A. Diffuse slowing B. Periodic sharp wave complexes C. Triphasic waves D. Spike-and-wave pattern

Answer 40

B

Question 41

What is the most common cause of dementia in the elderly? A. Alzheimer’s disease B. Lewy body dementia C. Vascular dementia D. Frontotemporal dementia

Answer 41

A

Question 42

What is the biggest risk factor for late-onset Alzheimer’s? A. APOE4 mutation B. Age C. Hypertension D. Smoking

Answer 42

B

Question 43

42-year-old man with Down syndrome presents with memory loss and confusion. What is the underlying genetic cause of his condition? A. Presenilin-1 mutation B. APP overexpression C. APOE4 mutation D. Tau hyperphosphorylation

Answer 43

B

Question 44

What neurotransmitter is most decreased in Alzheimer’s disease? A. Dopamine B. Acetylcholine C. GABA D. Serotonin

Answer 44

B HY Fact: Loss of cholinergic neurons in the nucleus basalis of Meynert → ↓ acetylcholine (ACh) → cognitive dysfunction.

Question 45

Which apolipoprotein increases the risk of sporadic Alzheimer’s disease?

Answer 45

HY Fact: ApoE2 is protective. ApoE4 ("four is for Alzheimer’s") increases sporadic AD risk.

Question 46

A 38-year-old man presents with progressive memory loss. Family history reveals multiple cases of early-onset dementia. What genetic mutation is most likely? A. ApoE4 B. Presenilin-1 C. Tau protein mutation D. Ubiquitinated TDP-43

Answer 46

B

Question 47

What brain region undergoes the earliest atrophy in Alzheimer’s disease? A. Frontal lobe B. Hippocampus C. Occipital lobe D. Cerebellum

Answer 47

B HY Fact: Hippocampal atrophy = first affected area (important for memory).

Question 48

Alzheimer’s patients are at risk of recurrent lobar hemorrhages due to deposition of which protein? A. Tau B. α-synuclein C. Amyloid-β D. Prion protein

Answer 48

C

Question 49

What is the primary intracellular protein accumulation in Alzheimer’s disease? A. Amyloid-β B. α-synuclein C. Hyperphosphorylated tau D. Prion protein

Answer 49

C

Question 50

Q: A post-mortem brain of an Alzheimer’s patient reveals eosinophilic rod-shaped inclusions in the hippocampus. What are these called? A. Lewy bodies B. Hirano bodies C. Pick bodies D. Negri bodies

Answer 50

B HY Fact: Hirano bodies = intracellular, eosinophilic, actin-rich inclusions. Found in Alzheimer’s, CJD, and other neurodegenerative diseases.

Question 51

A 45-year-old man presents with progressive memory loss and personality changes over the past 2 years. His father and uncle had similar symptoms in their 40s. Genetic testing reveals a mutation on chromosome 14. Which of the following best explains the pathogenesis of his condition? A. Increased β-amyloid production due to presenilin-1 mutation B. Increased tau phosphorylation leading to cytoskeletal disruption C. Accumulation of α-synuclein in cortical neurons D. Inactivation of superoxide dismutase-1 (SOD1) leading to oxidative stress

Answer 51

A

Question 52

A 78-year-old woman with a history of progressive memory loss is brought to the ER after a sudden-onset headache and right-sided weakness. CT scan reveals a lobar intracerebral hemorrhage in the parietal lobe. No history of hypertension or anticoagulant use. What is the most likely cause of this hemorrhage? A. Hypertensive arteriolosclerosis B. Amyloid-β deposition in cerebral vessels C. Charcot-Bouchard aneurysm rupture D. Ruptured saccular aneurysm

Answer 52

B

Question 53

A 72-year-old man is diagnosed with Alzheimer’s disease after experiencing gradual memory loss over several years. Autopsy of his brain would most likely reveal decreased activity in which of the following neurotransmitters? A. Dopamine B. Glutamate C. Acetylcholine D. GABA

Answer 53

C

Question 54

A 75-year-old woman with progressive cognitive decline dies from complications of her disease. Histologic examination of her brain reveals extracellular eosinophilic deposits in the gray matter and intracellular hyperphosphorylated tau aggregates. Which of the following best describes these findings? A. Lewy bodies and neurofibrillary tangles B. Amyloid plaques and neurofibrillary tangles C. Pick bodies and Hirano bodies D. Prion plaques and vacuolization

Answer 54

B

Question 55

A 70-year-old man is diagnosed with sporadic late-onset Alzheimer’s disease. His genetic testing reveals a polymorphism associated with an increased risk of AD. Which of the following proteins is most likely implicated? A. ApoE2 B. ApoE3 C. ApoE4 D. Presenilin-2

Answer 55

C