A 65-year-old woman comes to the office for evaluation of progressively worsening memory. The patient lives alone and considers herself "very independent"; however, she has recently forgotten to pay her bills on several occasions and also lost her way while driving in a previously familiar neighborhood 2 weeks ago. Review of systems reveals no other symptoms except for mild urinary urgency. The patient has a history of hypertension and hyperlipidemia. She does not use tobacco, alcohol, or illicit drugs. Temperature is 36.7 C (98 F), blood pressure is 130/90 mm Hg, pulse is 72/min, and respirations are 14/min. The lungs are clear to auscultation, and a grade 2/6 systolic ejection murmur is present. Abdominal examination shows no tenderness or masses. The cranial nerves are intact, funduscopy is normal, and there is no tremor. The patient immediately recalls all 3 of 3 items read to her, but 5 minutes later she can remember none of them. Her gait is broad-based and shuffling. Blood cell count and serum chemistry studies are within normal limits. Which of the following is the most likely underlying cause of this patient's symptoms?

Question

A 65-year-old woman comes to the office for evaluation of progressively worsening memory.  The patient lives alone and considers herself "very independent"; however, she has recently forgotten to pay her bills on several occasions and also lost her way while driving in a previously familiar neighborhood 2 weeks ago.  Review of systems reveals no other symptoms except for mild urinary urgency.  The patient has a history of hypertension and hyperlipidemia.  She does not use tobacco, alcohol, or illicit drugs.  Temperature is 36.7 C (98 F), blood pressure is 130/90 mm Hg, pulse is 72/min, and respirations are 14/min.  The lungs are clear to auscultation, and a grade 2/6 systolic ejection murmur is present.  Abdominal examination shows no tenderness or masses.  The cranial nerves are intact, funduscopy is normal, and there is no tremor.  The patient immediately recalls all 3 of 3 items read to her, but 5 minutes later she can remember none of them.  Her gait is broad-based and shuffling.  Blood cell count and serum chemistry studies are within normal limits.  Which of the following is the most likely underlying cause of this patient's symptoms?

Quizplus · Accepted Answer

11ec25c8_d5bb_46b3_bc81_f916d49c523c_MD0003_00 This patient has normal pressure hydrocephalus (NPH), a clinical syndrome characterized by gait abnormalities (broad-based gait, shuffling), cognitive impairment (memory deficits, impaired executive function), and urinary incontinence (often presenting as urinary urgency in early disease). NPH is thought to be due to decreased cerebrospinal fluid (CSF) absorption by the arachnoid granulations. Idiopathic NPH is associated with chronic periventricular ischemia and increased venous resistance, which may alter normal arachnoid function. NPH may also occur secondary to a variety of neurologic insults (eg, meningitis, subarachnoid hemorrhage) due to scarring and dysfunction of the granulations. As CSF accumulates, the ventricles expand to prevent elevation in intracranial pressure, resulting in the characteristic imaging findings of ventriculomegaly out of proportion to sulcal enlargement. Lumbar puncture demonstrates normal CSF studies and opening pressure, and clinical improvement after large volume CSF removal is diagnostic. Ventricular shunting is the definitive management. (Choice A) Accumulation of alpha-synuclein within dopaminergic neurons is consistent with Parkinson disease. Parkinson can cause a shuffling gait but also typically causes bradykinesia, rigidity, and a pill-rolling tremor; cognitive impairment is a late-stage finding, and urinary urgency would be unexpected. (Choice C) Amyloid deposition occurs in Alzheimer disease. Cognitive deficits present early in the disease; gait impairment and urinary incontinence may occur but typically much later in the disease course. Urinary urgency (as seen in this patient) is not associated with Alzheimer disease. (Choice D) Vitamin B₁₂ deficiency can cause dementia and subacute combined degeneration with ataxia and incontinence. However, patients typically also develop bilateral lower extremity paresthesias, glossitis, and macrocytic anemia. (Choice E) Frontotemporal dementia (loss of frontotemporal neurons) causes progressive dementia, but it is characterized by both prominent changes in personality/behavior and aphasia. Gait abnormalities and urinary urgency are uncommon. Educational objective: Normal pressure hydrocephalus is characterized by gait abnormalities, cognitive impairment, and urinary incontinence that often presents as urgency in early disease. It is thought to result from decreased CSF absorption with increased ventricular compliance, allowing for ventricular enlargement without chronically increasing intracranial pressure.

A 65-Year-Old Woman Comes to the Office for Evaluation of Progressively