Quiz: Have you mastered the differential diagnosis and examination of Alzheimer's disease?

Alzheimer's disease is a chronic, progressive neurodegenerative disease and the most common form of dementia, accounting for 60%-70% of global cases
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It is the most common type of dementia in the United States, Europe and other developed countries, with a prevalence of 6%-10%
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Since approximately 50 million people suffer from dementia (this number is expected to increase by 10 million cases each year), distinguishing Alzheimer's disease from other forms of dementia is essential to ensure early diagnosis and appropriate intervention
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How much do you know about the differential diagnosis and examination of Alzheimer's disease? This article will test everyone's understanding through 5 small questions, let's try it together
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Yimaitong compiles and organizes, please do not reprint without authorization
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Question 1: In the early stages of dementia, which of the following conditions can be observed for memory retention? A.
Alzheimer's disease and frontotemporal dementia (FTD) B.
Chronic traumatic encephalopathy (CTE) and FTDC.
Lewy body dementia ( DLB) and vascular dementia D.
Creutzfeldt-Jakob disease (CJD) and Alzheimer's disease slide to see the answer↓↓↓↓↓↓↓↓↓【Answer and analysis】C
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The two types of dementia that can retain memory are DLB and vascular dementia
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The following clinical features help distinguish DLB from Alzheimer's disease: ➤DLB patients often experience fluctuations in cognitive function, with varying degrees of alertness and attention (for example, excessive sleep during the day or sleep during the day despite adequate sleep at night> 2 hours, long time in a daze, confusion in speech)
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➤Up to 80% of DLB ​​patients will have hallucinations, but it is quite rare in Alzheimer's disease patients
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➤Compared with the late onset of Alzheimer's disease, the characteristics of spontaneous Parkinsonism are typical in the early stage of DLB
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➤Compared with patients with Alzheimer's disease, patients with DLB have extrapyramidal features relatively early
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➤Compared with the obvious anterograde memory loss which is an early sign of Alzheimer's disease, the anterograde memory loss in DLB patients is not obvious
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➤Compared with patients with Alzheimer's disease, DLB patients have more prominent executive function deficits and visual spatial impairments
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 Vascular dementia is the second most common form of dementia, which has a focal or diffuse effect on the brain, leading to a decline in cognitive function
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Fortunately, vascular disease can be prevented; therefore, early recognition and treatment are very important to prevent and slow down the progression of the disease
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Hypertension is the most common cause of vascular dementia
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 Both Alzheimer's disease and FTD (where primary progressive aphasia and frontal dementia are the main aspects) can cause severe memory loss
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However, unlike Alzheimer's disease, FTD initially manifests as a progressive deterioration of aphasia within a few years; the patient eventually exhibits progressive dementia
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 Although both CTE and FTD can cause severe memory loss, CTE is caused by athletes with repeated concussions and closed head injuries
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Repeated headaches, aggressiveness, and progressive dementia are signs of CTE
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Unlike Alzheimer's disease, the hippocampus of CTE patients does not show volume loss
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 CJD is a rare and rapidly progressing neurodegenerative disease that affects 1 out of every 1,000,000 people in the world
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There is no known cure for CJD, and treatment is supportive
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Most patients die within 1 year after diagnosis
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Question 2 Which of the following is most likely to be a manifestation of pseudo-dementia? A.
Frustration B.
Anxiety C.
Psychosis D.
Acute encephalopathy Slide to view the answer↓↓↓↓↓↓↓↓↓【Answer and analysis】A
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"Pseudo-dementia" refers to cognitive impairment similar to dementia
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Although a variety of underlying diseases can cause pseudodementia, the most common cause is depression, which is often referred to as depressive pseudodementia (DPD)
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Unlike Alzheimer's disease, when patients are treated for depression, the cognitive effects associated with DPD can usually be reversed
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 The effects of depression and Alzheimer's disease can cause overlapping symptoms: about 30%-50% of Alzheimer's patients also suffer from depression
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However, patients with Alzheimer's disease usually present with apathy, fatigue, and insufficiently motivated depression, while depression in elderly patients without dementia usually presents with mood changes (for example, feelings of sadness), suicidal thoughts, and changes in sleep and appetite
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 Anxiety, psychosis, and acute encephalopathy are unlikely to be similar to pseudodementia
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Question 3 The recommendations of the American Academy of Neurology (AAN) currently include which of the following laboratory studies on patients with suspected Alzheimer's disease? A.
Lyme disease test B.
Blood urea nitrogen/creatinine (BUN/Cr) ratio C.
C-reactive protein (CRP) test D.
Cobalamin and thyroid-stimulating hormone (TSH) levels slide to see the answer↓↓↓↓↓↓ ↓↓↓【Answer and Analysis】D
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AAN’s recommendations include measuring cobalamin (vitamin B12) and TSH levels in patients with suspected Alzheimer’s disease to rule out other causes
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According to the individual needs of the patient, it is up to the doctor to decide whether to perform other laboratory tests
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AAN does not recommend Lyme disease testing, BUN/Cr ratio evaluation, or CRP measurement for patients with suspected Alzheimer's disease
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Question 4 Why should brain MRI and CT examinations be performed on patients with suspected Alzheimer's disease? A.
Detection of brain sclerosis associated with Alzheimer's disease B.
Detection of brain calcification associated with Alzheimer's disease C.
Detection of other causes of dementia (such as stroke, tumor, small vessel disease) D.
Measurement of brain size slip Check the answer↓↓↓↓↓↓↓↓↓【Answer and Analysis】C
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According to AAN’s recommendations, for patients with suspected Alzheimer’s disease, brain MRI and CT examinations should be performed to detect other causes of dementia (such as stroke, tumor, small vessel disease)
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In clinical studies, coronal MRI, horse body atrophy (an important structure that mediates the memory process) is considered to be an effective biomarker for neuropathology of Alzheimer's disease
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Nevertheless, the measurement of hippocampal volume is not used in routine clinical care for the diagnosis of Alzheimer's disease
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 Cerebral sclerosis and calcification are not related to Alzheimer's disease
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Although studies of asymptomatic patients indicate that brain size (that is, the area of ​​the cerebral cortex) may help predict the risk of Alzheimer's disease, measuring brain size is not necessary for the diagnosis of Alzheimer's disease
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Question 5 Which genotypes are associated with the highest risk of Alzheimer's disease? A.
CFTR gene B.
BRCA1 gene C.
PARK7 gene D.
Apolipoprotein E (APOE) allele Slide to view the answer↓↓↓↓↓↓↓↓↓【Answer and analysis】D
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Genotyping of APOE alleles is a research tool that helps determine the risk of Alzheimer’s disease in a patient population, but until recently it had little value in clinical diagnosis and management plans for individual patients ( If any)
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The APOE genotypes with the highest risk of Alzheimer's disease are ε43 and ε44, and the lowest risk are ε22, ε32, ε42, and ε33
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 The CFTR gene is related to cystic fibrosis
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The BRCA1 gene is associated with an increased risk of breast and ovarian cancer
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The PARK7 gene (also known as DJ-1) is related to early-onset Parkinson's disease
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Yimaitong compiled from: Jasvinder P.
Chawla.
Fast Five Quiz: Alzheimer's Disease Differential Diagnosis and Workup-Medscape-Jan 19, 2021.