WBR0205

Author	PageAuthor::William J Gibson
Exam Type	ExamType::USMLE Step 1
Main Category	MainCategory::Microbiology, MainCategory::Pathology
Sub Category	SubCategory::Neurology, SubCategory::Infectious Disease
Prompt	[[Prompt::A 56 year old woman is brought to the emergency room by her husband. He reports that one week ago she appeared to be increasingly forgetful. At first forgetting things like the car keys, then forgetting appointments. Now she has forgotten the names of her children and her home address. Physical exam is remarkable for an abnormal gait and widespread neurologic deficits particularly in executive function. Brain biopsy would most likely show which of the following?]]
Answer A	AnswerA::Lymphocytic infiltrate
Answer A Explanation	AnswerAExp::This corresponds to encephalitis, which may show more systemic symptoms such as fever and focal neurologic deficits.
Answer B	AnswerB::Alpha Synuclein deposits
Answer B Explanation	AnswerBExp::This corresponds to Lewy Body dementia which would not have the acute onset seen in this patient.
Answer C	AnswerC::Beta pleated sheets
Answer C Explanation	AnswerCExp::See explanation
Answer D	AnswerD::Abnormally phosphorylated tau protein
Answer D Explanation	AnswerDExp::This corresponds to Neurofibrillary tangles, pathologic changes associated with Alzheimer’s disease. Alzheimer’s disease does not have the acute onset seen in this patient.
Answer E	AnswerE::Beta-amyloid deposits
Answer E Explanation	AnswerEExp::This corresponds to the composition of senile plaques, pathologic changes seen in Alzheimers disease. Alzheimer’s disease does not have the acute onset seen in this patient.
Right Answer	RightAnswer::C
Explanation	[[Explanation::The patient in this vignette is suffering from Creutzfeldt-Jakob disease, an infectious disease caused by the abnormal aggregation of prions. Prions are an abnormally folded protein composed of beta pleated sheets which act as a scaffold to induce the conversion of other proteins into an abnormally folded prion state as well. Creutzfeldt-Jakob disease is characterized by the rapid onset of dementia in otherwise well people. It is universally fatal and there is no treatment. Educational Objective: Creutzfeldt-Jakob disease is characterized by rapidly progressive dementia, and is caused by prions which are proteins folded as beta pleated sheets. References: First Aid 2014 page 483]]
Approved	Approved::Yes
Keyword	WBRKeyword::Neurology, WBRKeyword::Pathology, WBRKeyword::Neuropathology, WBRKeyword::Prion, WBRKeyword::Creutzfeldt-Jakob disease, WBRKeyword::Dementia, WBRKeyword::Mental status change
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