Dementia and Cognitive Disorders Flashcards
An 82-year-old man has 6 months of worsening memory loss. His family is concerned, and he is taken to a physician. Following an extensive evaluation and neuropsychological testing, he is diagnosed with dementia.
- The most common cause of dementia in the general population is
a. Epilepsy
b. Vascular disease
c. Alzheimer’s disease
d. Parkinson’s disease
e. Head trauma
C
(Bradley, p 1703.) Alzheimer’s disease accounts for as much as 50% of the dementia in the general population confirmed at autopsy; Parkinson’s disease accounts for only about 1%. Only 80 years ago, neurosyphilis was the most common cause of dementia, but the introduction of penicillin reduced- though it did not eliminate-this spirochetal disease as a cause of dementia. As the population ages, the incidence and prevalence of Alzheimer’s disease are increasing. The dementia caused by Alzheimer’s disease is progressive over the course of years. Language disturbances may appear even before memory problems.
An 82-year-old man has 6 months of worsening memory loss. His family is concerned, and he is taken to a physician. Following an extensive evaluation and neuropsychological testing, he is diagnosed with dementia.
- His physician believes that the patient has Alzheimer’s disease. Which of the following is most characteristic of the brain in patients with Alzheimer’s disease?
a. Neuronal loss in the cerebral cortex
b. Demyelination in the cerebral cortex
c. Posterior column degeneration
d. Neuronal loss in the cerebellar cortex
e. Pigmentary degeneration in the hippocampus
A
(Bradley, pp 1707–1708.) The most prominent characteristics of Alzheimer’s disease are neuronal loss, fibrillary tangles, loss of synapses, and amyloid (or neuritic) plaque formation. These histopathologic features are evident throughout the cerebral cortex, but the neurofibrillary tangles and neuronal loss are most prominent in the hippocampus and adjacent structures of the temporal lobe. The tangles and loss of synapses are most closely linked to the development of dementia. The cell loss may be so substantial that the patient develops marked compensatory enlargement of the ventricles, a condition called hydrocephalus ex vacuo.
An 82-year-old man has 6 months of worsening memory loss. His family is concerned, and he is taken to a physician. Following an extensive evaluation and neuropsychological testing, he is diagnosed with dementia.
- In the dementia associated with Alzheimer’s disease, the EEG will usually show
a. Spike-and-wave discharges
b. Periodic frontal lobe discharges
c. Focal slowing
d. Generalized background slowing
e. An isoelectric record
D
(Rowland, pp 70–71.) The background rhythm on the normal adult EEG is α activity at 8 to 12 Hz. With Alzheimer’s disease, the frequency of this rhythm may slow, and the amount of time in which this rhythm is evident when the patient is lying relaxed with eyes closed may drop substantially. Periodic discharges in the form of sharp waves or spikes may develop during Creutzfeldt-Jakob disease. EEG is otherwise not especially helpful in distinguishing between the common causes of dementia.
- A 55-year-old man has steep decline in his cognitive abilities over a 3-month period. Initial testing is nondiagnostic. He continues to progress and develops myoclonus and a left hemiparesis. Eventually he dies of an aspiration about 8 months after the onset of symptoms. In the diseases that cause dementia, myoclonus is usually most evident in
a. Alzheimer’s disease
b. Creutzfeldt-Jakob disease
c. Parkinson’s disease
d. Huntington’s disease
e. Pick’s disease
B
(Rowland, p 171.) Creutzfeldt-Jakob disease is a spongiform encephalopathy that produces dementia over the course of months. It is caused by the accumulation within the brain of an abnormal formof a normal protein that resists degradation by proteinases (a proteinase resistant protein, prion protein, or PrP). Myoclonic jerks-abrupt involuntary muscle contractions that may produce brief limb or facial movements-usually appear at some time in the course of this disease. These are often stimulus-sensitive, such that loud noises may provoke them. Similar movements may develop with Huntington’s disease, but these patients usually develop more constant and fluid limb movements called chorea.
- The brain of the adult with trisomy 21 (Down syndrome) exhibits many of the histopathologic features of which of the following?
a. Tay-Sachs disease
b. Friedreich’s disease
c. Pick’s disease
d. Parkinson’s disease
e. Alzheimer’s disease
E
(Bradley, pp 1712–1713.) Up to 90% or more of patients with trisomy 21 who die after age 30 have Alzheimer’s-type changes in the brain. The histopathologic features of Alzheimer’s disease may be evident in the person with Down syndrome at any age. That a hereditary form of Alzheimer’s disease was found linked to chromosome 21 raised hopes that a single mutation was the cause of the problem, but this was subsequently negated by the finding of hereditary forms of Alzheimer’s linked to chromosome 19 and sporadic Alzheimer’s associated with defects on neither of these chromosomes. Aside from persons with Down syndrome, Alzheimer’s disease only rarely develops in relatively young people.
An 80-year-old man has a history of 2 years of progressive gait disturbance and incontinence, which had been attributed to old age and prostatism. Within the past 3 months, he has been forgetful, confused, and withdrawn. His gait is short-stepped, and he turns very slowly, almost toppling over. He has a history of head trauma from 30 years ago. His CT scan is shown below.
- The most likely diagnosis is
a. Alzheimer’s disease
b. Creutzfeldt-Jakob disease
c. Progressive multifocal leukoencephalopathy (PML)
d. Normal-pressure hydrocephalus
e. Chiari malformation
D
(Bradley, pp 1556–1557.) Normal-pressure hydrocephalus (NPH) is a chronic, communicating form of hydrocephalus affecting elderly adults. The cause is unknown, but it may relate to prior episodes of trauma, infection, or subarachnoid hemorrhage. The clinical picture typically includes a triad of gait disturbance, dementia, and incontinence. The gait disorder may be difficult to distinguish from that of Parkinson’s disease, and has been labeled an apraxic gait as patients often have difficulty even lifting their feet off the floor, though they have no weakness and may perform motor tasks well with the legs when seated. CT or MRI in these patients usually shows enlargement of the temporal and frontal horns of the lateral ventricles out of proportion to the degree of cortical atrophy. There may also be a squaring off or blunted appearance of the frontal horns, and increased signal on T2-weighted images may be seen in the periventricular regions, consistent with the presence of fluid related to transependymal flow of CSF.
An 80-year-old man has a history of 2 years of progressive gait disturbance and incontinence, which had been attributed to old age and prostatism. Within the past 3 months, he has been forgetful, confused, and withdrawn. His gait is short-stepped, and he turns very slowly, almost toppling over. He has a history of head trauma from 30 years ago. His CT scan is shown below.
- The patient undergoes lumbar puncture. Forty milliliters of fluid are removed. Three hours later, he is able to walk unassisted and turns well. Spinal fluid would be expected to show
a. No abnormalities
b. Elevated protein
c. Low protein
d. Atypical lymphocytes
e. Low glucose
A
(Bradley, pp 1556–1557.) The CSF in patients with NPH is typically normal. Abnormalities in protein or cellularity should suggest an alternate diagnosis. The pressure of the CSF is also usually normal, although studies using long-term pressure monitoring in these patients has shown that they have periods of pressure elevation, often at night.
An 80-year-old man has a history of 2 years of progressive gait disturbance and incontinence, which had been attributed to old age and prostatism. Within the past 3 months, he has been forgetful, confused, and withdrawn. His gait is short-stepped, and he turns very slowly, almost toppling over. He has a history of head trauma from 30 years ago. His CT scan is shown below
- The patient undergoes ventriculoperitoneal shunt placement. He is discharged 2 days later, his gait and cognition much improved. The fol-lowing morning, his wife finds him lying in bed, very confused and com¬plaining of a headache. He is unable to walk. The surgeon who performed the procedure is concerned that these new symptoms are due to
a. Chemical meningitis
b. Subdural hematoma
c. Epidural hematoma
d. Seizures
e. Bacterial ventriculitis
B
(Bradley, pp 1556–1557.) Up to 28% of patients who undergo ventriculoperitoneal shunting for NPH may suffer major complications, including subdural hematoma. Subdural hematoma occurs because the reduction in intracranial pressure brought on by the reduction in CSF volume may cause the brain to pull away from the covering meninges, stretching and potentially rupturing the bridging veins.
A 67-year-old man has a history of progressive memory loss for 2 years. His examination is otherwise normal. A diagnosis of Alzheimer’s disease is made.
- Which of the following medications may retard the progress of this patient’s deterioration?
a. Donepezil
b. L-dopa
c. Risperidone
d. Prednisone
e. Vitamin B12
A
(Bradley, p 1712.) Several modest advances in the treatment of Alzheimer’s disease have occurred in the past decade. Recognition of the fact that there is a cholinergic deficit in the brains of patients with Alzheimer’s disease has led to the development of acetylcholinesterase inhibitors designed to augment the cholinergic neurotransmitter system. Two different agents that have been used in the United States are tacrine, which can cause hepatic dysfunction, and donepezil, which is better tolerated. The effects are modest and act to slow cognitive decline as assessed by scales of cognitive function. There is still no cure for Alzheimer’s disease.
A 67-year-old man has a history of progressive memory loss for 2 years. His examination is otherwise normal. A diagnosis of Alzheimer’s disease is made.
- Which of the following medications may reduce the chances of his being placed into a nursing home?
a. Vitamin B12
b. Vitamin E
c. Estrogen therapy
d. Amantadine
e. Haloperidol
B
(Bradley, p 1712.) Vitamin E has also been shown to delay the progression of dementia in Alzheimer’s disease. Its mechanism of action is presumed to be related to its ability to limit free radical formation, oxidative stress, and lipid peroxidation. In one clinical trial, 2000 IU of vitamin E daily led to a delay in time to institutional placement, dependence, severe dementia, or death. Interestingly, it did not appear to reduce the decline on cognitive test scores. The effect is similar to that of the monoamine oxidase inhibitor selegiline, but there was no benefit to using both drugs together.
A 67-year-old man has a history of progressive memory loss for 2 years. His examination is otherwise normal. A diagnosis of Alzheimer’s disease is made.
- Language testing is most likely to uncover which of the following deficits?
a. No abnormalities
b. Mutism
c. Conduction aphasia
d. Transcortical sensory aphasia
e. Transcortical global aphasia
D
(Victor, p 1110.) The major clinical features of Alzheimer’s disease are memory impairment, aphasia, apraxia, and neuropsychiatric impairment, including mood disturbances, delusions and hallucinations, personality changes, and behavior disturbances. The language disturbance may take the form of decreased fluency, dysnomia, and transcortical sensory aphasia, which refers to a reduction in the ability to understand complex linguistic structures. Repetition of verbal material is intact.
- A 73-year-old man steps out of the shower on a Saturday evening and is unable to remember that he and his wife have tickets to a play. He asks her repeatedly, “Where are we going?” He appears bewildered, but is alert, knows his own name, speaks fluently, and has no motor deficits. He has no history of memory disturbance, and after 8 h returns to normal.
a. Transient global amnesia
b. Normal-pressure hydrocephalus
c. Alzheimer’s disease
d. Parkinson’s disease
e. Creutzfeldt-Jakob disease
f. Vitamin B12 deficiency
g. Hypothyroidism
h. Huntington’s disease
i. Rett syndrome
j. Multi-infarct dementia
k. General paresis
l. Temporal lobe epilepsy
(SELECT 1 DIAGNOSIS)
A
(Bradley, pp 1129–1130.) Transient global amnesia (TGA) refers to an episode of complete and reversible anterograde and retrograde memory loss lasting up to 24 h. Patients have a persistent loss of memory for the time of the attack. During the episode, patients often appear bewildered and ask repeated questions. They retain personal identity (unlike characters suffering from transient amnesia in television shows) and can perform complex cognitive and motor tasks. Transient global amnesia usually affects middle-aged or older men and often occurs in the setting of an emotional or other stressor, such as physical or sexual exertion. Although it shares features of TIA, it is not associated with an increased risk of stroke. Nonetheless, a vascular evaluation is often appropriate, particularly in atypical or repeated cases and in the presence of risk factors for stroke. Most patients experience only a single episode. Some have stressed TGA’s similarity to migraine and hypothesized that it is related to migrainous ischemia of the medial temporal lobe structures.
- A 50-year-old woman began complaining of double vision and blurry vision 3 months ago and has since had diminishing interaction with her family, a paucity of thought and expression, and unsteadiness of gait. Her whole body appears to jump in the presence of a loud noise. An MRI scan and routine CSF examination are unremarkable. (SELECT 1 DIAGNOSIS)
a. Transient global amnesia
b. Normal-pressure hydrocephalus
c. Alzheimer’s disease
d. Parkinson’s disease
e. Creutzfeldt-Jakob disease
f. Vitamin B12 deficiency
g. Hypothyroidism
h. Huntington’s disease
i. Rett syndrome
j. Multi-infarct dementia
k. General paresis
l. Temporal lobe epilepsy
E
(Bradley, pp 1424–1425.) The neurological complaints occurring early in the course of Creutzfeldt-Jakob disease are often cerebellar or visual. Patients may complain of ataxia, clumsiness, or dysarthria, as well as diplopia, distorted vision, blurred vision, field defects, changes in color perception, and visual agnosia. Ultimately cortical blindness may occur. The diagnosis may be supported by the finding of periodic sharp waves at a 1- to 2-Hz frequency on EEG and the finding of elevated protein 14-3-3 in CSF. The typical EEG pattern is found in up to 80% of patients at some point during the course of the illness. An MRI may show a pattern of increased T2 signal in the basal ganglia in many, but not all, cases.
- A 2-year-old girl developed normally until the past year. She has since become unable to speak or otherwise communicate with her parents, sits in a chair, and makes nearly continuous wringing movements with her hands. She also has episodes of breath holding alternating with hyperventilation. (SELECT 1 DIAGNOSIS)
a. Transient global amnesia
b. Normal-pressure hydrocephalus
c. Alzheimer’s disease
d. Parkinson’s disease
e. Creutzfeldt-Jakob disease
f. Vitamin B12 deficiency
g. Hypothyroidism
h. Huntington’s disease
i. Rett syndrome
j. Multi-infarct dementia
k. General paresis
l. Temporal lobe epilepsy
I
(Swaiman, pp 612, 836–839.) Rett syndrome is a presumed X-linked genetic disorder that affects only girls; the homozygous version is thought to be fatal in male offspring. Usually the prenatal, perinatal, and early childhood development appear normal or nearly so, and then the girl undergoes rapid regression in cognitive status in early childhood, generally during the second year of life. There is loss of previously acquired language skills and effective eye contact, as well as purposeful hand movement. Stereotypic hand movements develop, usually taking the form of hand wringing, but also including tapping, patting, and at times hand-mouth movements. Seizures may also occur. Etiology is unknown, and there is no treatment.
- A 17-year-old girl develops mild dementia, tremor, and rigidity. Her father died in his fourth decade of life of a progressive dementing illness associated with jerking (choreiform) limb movements. On exposure to L-dopa, she becomes acutely agitated and has jerking limb movements.
a. Transient global amnesia
b. Normal-pressure hydrocephalus
c. Alzheimer’s disease
d. Parkinson’s disease
e. Creutzfeldt-Jakob disease
f. Vitamin B12 deficiency
g. Hypothyroidism
h. Huntington’s disease
i. Rett syndrome
j. Multi-infarct dementia
k. General paresis
l. Temporal lobe epilepsy
(SELECT 1 DIAGNOSIS)
H
(Bradley, pp 1719–1720.) Dementia is a prominent feature of Huntington’s disease. Apathy and depression occur commonly, and a schizophreniform illness may be the presenting manifestation at times. The dementia itself is subcortical, characterized by impairment in executive function and concentration, without the classic cortical features of Alzheimer’s disease, such as aphasia, apraxia, and amnesia.
