Overview Snapshot A 58-year-old male presents with difficulties in concentration and worsening insomnia. These symptoms have been progressively worsening over the past month. Startle myoclonus is appreciated on physical examination. Electroencephalography shows biphasic sharp wave patterns. Introduction Prions misfolded intracellular proteins that lead to neurodegeneration PrPc (normal; α-helix isoform) undergoes conformational change into PrPsc (abnormal; β-pleated sheet isoform) PrPsc is resistant to intracellular proteases can further induce PrPc into PrPsc → cytoplasmic vacuoles and neuronal death Spongiform encephalopathy Creutzfeld-Jakob disease (CJD) most common can be sporadic, familial or acquired acquired via iatrogenic or dietary methods Presentation Symptoms rapidly progressive dementia occurs in weeks to months myoclonus startling the patient can induce myoclonus ataxia distrubances in vision e.g., visual field defects, abnormalities in perception Evaluation Histology spongiform cortex large intracellular vacuoles Electroencephalography spike (sharp) wave pattern Cerebral spinal fluid (CSF) 14-3-3 protein Magnetic resonance imaging hyperintensity in the head of the caudate and putamen on T2-weighted and FLAIR images Differential Alzheimer disease Frontotemporal dementia Vascular dementia HIV-associated dementia Treatment Supportive No effective treatment Prognosis, Prevention, and Complications Prognosis death typically within 1 year of symptom onset Prevention iatrogenic screen dura mater and cornea donors incinerate medical tools used in patients with/suspective of CJD recombinant human growth hormone use instead of human derived Complications seizures aspiration pneumonia PrPsc
QUESTIONS 1 of 2 1 2 Previous Next (M1.NE.15.4671) A 65-year-old man with no significant medical history begins to have memory loss and personality changes. Rapidly, over the next few months his symptoms increase in severity. He experiences a rapid mental deterioration associated with sudden, jerking movements, particularly in response to being startled. He has gait disturbances as well. Eventually, he lapses into a coma and dies approximately ten months after the onset of symptoms. Which of the following would most likely be seen on autopsy of the brain in this patient? Tested Concept QID: 107137 FIGURES: A B C D E Type & Select Correct Answer 1 A 10% (7/72) 2 B 10% (7/72) 3 C 54% (39/72) 4 D 17% (12/72) 5 E 8% (6/72) M 2 Question Complexity D Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 3 Review tested concept (M1.NE.14.24) A 70-year-old woman with no significant medical history begins to experience memory loss and personality changes. Over the next few months, her symptoms become more severe, as she experiences rapid mental deterioration. She also starts to have sudden, jerking movements in response to being startled and gait disturbances. Eventually, she lapses into a coma and dies eight months after the onset of symptoms. What process likely caused this woman's illness? Tested Concept QID: 101688 Type & Select Correct Answer 1 Loss of dopaminergic neurons in the substantia nigra pars compacta. 8% (5/66) 2 Autoimmune inflammation and demyelination of the central nervous system. 2% (1/66) 3 Autoimmune inflammation and demyelination of the peripheral nervous system. 3% (2/66) 4 Conversion of a protein from an a-helix to a ß-pleated form, which resists degradation. 68% (45/66) 5 Frontotemporal atrophy and the accumulation of intracellular, aggregated tau protein. 20% (13/66) M 2 Question Complexity E Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 4 Review tested concept