Dementia is failure of the content portions of consciousness with relatively preserved alerting functions.





Dementia is an acquired deterioration in cognitive abilities that impairs the successful performance of activities of daily living.

 Clinical Differentiation of the Major Dementias
Disease First Symptom Mental Status Neuropsychiatry Neurology Imaging
AD Memory loss Episodic memory loss Irritability, anxiety, depression Initially normal Entorhinal cortex and hippocampal atrophy
FTD Apathy; poor judgment/insight, speech/language; hyperorality Frontal/executive and/or language; spares drawing Apathy, disinhibition, overeating, compulsivity May have vertical gaze palsy, axial rigidity, dystonia, alien hand, or MND Frontal, insular, and/or temporal atrophy; usually spares posterior parietal lobe
DLB Visual hallucinations, REM sleep behavior disorder, delirium, Capgras syndrome, parkinsonism Drawing and frontal/executive; spares memory; delirium-prone Visual hallucinations, depression, sleep disorder, delusions Parkinsonism Posterior parietal atrophy; hippocampi larger than in AD
CJD Dementia, mood, anxiety, movement disorders Variable, frontal/executive, focal cortical, memory Depression, anxiety, psychosis in some Myoclonus, rigidity, parkinsonism Cortical ribboning and basal ganglia or thalamus hyperintensity on diffusion/FLAIR MRI
Vascular Often but not always sudden; variable; apathy, falls, focal weakness Frontal/executive, cognitive slowing; can spare memory Apathy, delusions, anxiety Usually motor slowing, spasticity; can be normal Cortical and/or subcortical infarctions, confluent white matter disease

Abbreviations: AD, Alzheimer disease; CBD, cortical basal degeneration; CJD, Creutzfeldt-Jakob disease; DLB, dementia with Lewy bodies; FLAIR, fluid-attenuated inversion recovery; FTD, frontotemporal dementia; MND, motor neuron disease; MRI, magnetic resonance imaging; PSP, progressive supranuclear palsy; REM, rapid eye movement.


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Complications of Injecting Drug Use

  • Local problems—Abscess (Figures 240-2 
    Image not available.

    A 32-year-old woman with type 1 diabetes developed large abscesses all over her body secondary to injection of cocaine and heroin. Her back shows the large scars remaining after the healing of these abscesses. (Courtesy of ­Richard P. Usatine, MD.)

    and 240-3; Abscess), cellulitis, septic thrombophlebitis, local induration, necrotizing fasciitis, gas gangrene, pyomyositis, mycotic aneurysm, compartmental syndromes, and foreign bodies (e.g., broken needle parts) in local areas.2
    • IDUs are at higher risk of getting methicillin-resistant Staphylococcus aureus(MRSA) skin infections that the patient may think are spider bites (Figure 240-4).
    • Some IDUs give up trying to inject into their veins and put the cocaine directly into the skin. This causes local skin necrosis that produces round atrophic scars (Figure 240-5).
  • IDUs are at risk for contracting systemic infections, including HIV and hepatitis B or hepatitis C.
    • Injecting drug users are at risk of endocarditis, osteomyelitis (Figures 240-6and 240-7), and an abscess of the epidural region. These infections can lead to long hospitalizations for intravenous antibiotics. The endocarditis that occurs in IDUs involves the right-sided heart valves (see Chapter 50, Bacterial Endocarditis).2 They are also at risk of septic emboli to the lungs, group A β-hemolytic streptococcal septicemia, septic arthritis, and candidal and other fungal infections.


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A 72-year-old right-handed male with a history of atrial fibrillation and chronic alcoholism is evaluated for dementia. His son gives a history of a stepwise decline in the patient’s function over the last 5 years with the accumulation of mild focal neurologic deficits. On examination, he is found to have a pseudobulbar affect, mildly increased muscle tone, and brisk deep tendon reflexes in the right upper extremity and an extensor plantar response on the left. The history and examination are most consistent with which of the following?



A 73-year-old man with a history of an enlarged prostate presents to the emergency room complaining of repeated falls. His wife admits that during the past 3 weeks he has had an unsteady gait, urinary incontinence, and memory disturbances. His medical, surgical and family histories are unremarkable. He has never smoked or taken any recreational drugs. He drinks alcohol socially. His laboratory tests are all normal. A CT scan of the head shows slightly enlarged ventricles and slightly compressed gyri.
What is the most likely diagnosis of this patient's condition?
A- Normal pressure hydrocephalus
B- Alzheimer's disease
C- Middle cerebral artery stroke
D- Anterior pituitary adenoma
E- Trauma to the head due to elderly abuse


You are evaluating a previously healthy 73-year-old man with 3–4 months of cognitive decline as reported by his loving wife and daughter. They report that the patient was fully engaged in gardening and competitive board games; however, over the last 6 months, his garden has gone untended, and he expresses absolutely no interest in board games. He also has inappropriate outbursts of rage in social situations, such as in the mall. Over the last 2 months, he’s gained about 15 pounds and always seems to be eating or snacking. His only medication is a atorvastatin, which he’s been taking for 20 years. Based on this history, you are most concerned about which of the following diagnoses?

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The correct answer is D. You answered A.




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