Demyelinating Disorders

A 55-year-old male with a history of chronic alcohol use and malnutrition presents with severe hyponatremia. Following rapid correction of his sodium levels, he develops acute quadriparesis, dysarthria, and confusion. An MRI of the brain reveals a symmetric T2 hyperintense lesion centered in the pons. Which demyelinating disorder most accurately explains this clinical presentation?

A 10-year-old boy, with a remote history of measles infection in infancy, presents with progressive cognitive decline, behavioral changes, and myoclonic jerks over several months. His school performance has notably deteriorated, and an EEG reveals periodic sharp wave complexes. A brain MRI shows multifocal white matter lesions with patchy contrast enhancement. Which demyelinating disorder is most likely responsible for this presentation?

A 28-year-old female reports numbness and weakness in her right leg, which has progressed over a few days. She also reports experiencing transient vision loss in her left eye six months prior. A neurological examination reveals hyperreflexia, spasticity, and a positive Lhermitte sign. An MRI of the brain and spinal cord displays multiple periventricular white matter lesions on T2-weighted imaging, with some lesions showing enhancement. Which of the following demyelinating disorders is the most likely explanation for this patient's combined symptoms and imaging findings?

An 80-year-old woman is brought to the clinic by her daughter, who reports that her mother has been experiencing a gradual onset of memory loss, impaired language skills, and increasing disorientation over the past three years. A neurological examination reveals diffuse cortical atrophy without any focal deficits. An MRI of the brain demonstrates widened sulci, ventricular enlargement, and marked hippocampal atrophy. Which degenerative disorder best explains this patient’s array of clinical and imaging findings?

A 50-year-old man with no significant past medical history develops rapidly progressive dementia over several months, which is accompanied by ataxia, myoclonus, and visual disturbances. An EEG reveals periodic sharp wave complexes, and a brain MRI demonstrates cortical ribboning with basal ganglia involvement. Which degenerative disorder best explains this rapidly progressive clinical picture?

A 68-year-old man presents with a 2-year history of progressively worsening motor symptoms. He reports a tremor in his right hand that is MOST noticeable at rest and improves with voluntary movement. On examination, he demonstrates a shuffling gait, cogwheel rigidity, and bradykinesia. His son notes that he seems more despondent recently, which he attributes to these physical changes. A follow-up psychiatric consultation shows mild depression. Given the patient's MOST prominent symptoms, what is the most likely diagnosis?

A researcher is investigating the pathogenesis of Multiple Sclerosis (MS). They hypothesize that certain environmental and genetic factors may contribute to the development of the disease. Based on established risk factors for MS, which of the following patients would be MOST likely to develop MS?

A 45-year-old patient with a history of intravenous drug use is admitted to the hospital due to altered mental status and progressive weakness. An MRI of the brain reveals multiple focal areas of demyelination without mass effect. The neurologist suspects Progressive Multifocal Leukoencephalopathy (PML). Which of the following underlying conditions would be the MOST likely risk factor for the development of PML in this patient?

A 60-year-old male presents with gait instability, urinary incontinence, and cognitive decline. Neuroimaging reveals hydrocephalus with enlarged ventricles. Given the clinical triad and imaging findings, which of the following degenerative disorders is the MOST likely diagnosis?

A 25-year-old female presents to the emergency department complaining of acute ascending muscle weakness and paralysis that started in her legs and is now progressing upwards. She reports having had a diarrheal illness caused by a Campylobacter jejuni infection approximately two weeks ago. Based on this history, which of the following demyelinating disorders are you most suspecting?

A researcher is investigating potential therapeutic targets for Alzheimer's disease. They are focusing on neurotransmitter systems that are implicated in the pathophysiology of the disease. Which neurotransmitter system would be the MOST relevant for developing targeted therapies for Alzheimer's disease?

A neurologist is evaluating a patient with suspected Charcot-Marie-Tooth disease (CMT). Which of the following genetic mutations is MOST commonly associated with this condition?

A 70-year-old patient presents with cognitive decline, visual hallucinations, and parkinsonism. His family notes that his cognitive abilities fluctuate significantly throughout the day. Which of the following degenerative disorders is the MOST likely diagnosis?

A researcher is investigating potential biomarkers for early detection of Alzheimer's disease. Which of the following pathological hallmarks would be the MOST relevant to assess in cerebrospinal fluid (CSF) samples?

A 40-year-old male presents with behavioral changes, including disinhibition and impaired social cognition. His family reports that he used to be a successful businessman but now makes poor financial decisions and lacks empathy. Which of the following degenerative disorders is MOST likely responsible for these symptoms?

A pediatric neurologist is evaluating a 6-month-old infant who presents with progressive loss of motor skills, spasticity, hypotonia, and ataxia. The neurologist suspects a leukodystrophy. Which of the following characteristics is the MOST important in classifying leukodystrophies?

A 55-year-old patient with a history of end-stage renal disease (ESRD) is admitted to the hospital with altered mental status and confusion. His serum sodium level is severely low at 115 mEq/L. The medical team rapidly corrects his sodium level to 135 mEq/L over 24 hours. A few days later, the patient develops quadriparesis, dysarthria, and dysphagia. What is the MOST likely underlying cause of these new neurological deficits?

A 30-year-old female presents to the clinic with episodic neurological symptoms, including optic neuritis, weakness in her left leg, and paresthesias in her right arm. Her symptoms have been occurring intermittently over the past few years, with periods of remission in between. An MRI of the brain reveals multiple white matter lesions disseminated in space and time. Laboratory tests show elevated IgG levels in her cerebrospinal fluid (CSF). Which of the following pathological processes BEST explains this patient's clinical presentation and test results?

A 75-year-old female presents with a gradual decline in cognitive function, characterized by memory loss, impaired judgment, and difficulty with problem-solving. Her family reports that she also experiences visual hallucinations and fluctuations in alertness and attention. Based on these clinical findings, which of the following neurodegenerative diseases should you suspect?

A 50-year-old male presents with rapidly progressive dementia coupled with myoclonus and ataxia. An electroencephalogram (EEG) displays periodic sharp wave complexes, and brain MRI shows cortical ribboning. These signs and symptoms suggest which kind of neurodegeneration?

A 28-year-old pregnant woman at 30 weeks' gestation comes to your clinic saying that she suddenly lost feeling in her feet. You determine it is an acute lower motor neuron paralysis, with elevated protein in the cerebrospinal fluid. What is the MOST likely diagnosis?

A patient is diagnosed with metachromatic leukodystrophy (MLD), a type of autosomal recessive leukodystrophy. Which of the following enzyme deficiencies is the underlying cause of MLD?

A 65-year-old male patient is admitted to the hospital with memory loss, cognitive impairment, and personality changes. A neurological examination reveals rigidity, bradykinesia, and postural instability. The patient's family reports that he has experienced visual hallucinations and fluctuations in alertness. What neuropathological finding is MOST likely associated with these clinical manifestations?

Which of the following is the MOST common subtype of spongiform encephalopathy in humans?

A 40-year-old male patient presents with rapidly progressive motor neuron degeneration, leading to muscle weakness, spasticity, and respiratory failure. The neurologist suspects amyotrophic lateral sclerosis (ALS). Identify a primary pathological finding associated with ALS.

A newborn screening reveals a deficiency in galactocerebrosidase (GALC). This newborn is at risk for which progressive neurodegenerative disorder?

A 50-year-old male patient with HIV/AIDS presents with progressive cognitive decline, behavioral changes, and motor deficits. The patient's CD4+ count is low. An MRI of the brain shows multifocal white matter lesions without contrast enhancement. What demyelinating condition is MOSST likely responsible for these findings?

A patient presents with progressive cognitive impairment, ataxia, and myoclonus. An electroencephalogram (EEG) shows periodic sharp wave complexes. Which of the following biological agents is MOST likely attributable to these clinical findings?

A 35-year-old female presents to the clinic complaining of relapsing and remitting episodes of optic neuritis, paresthesias, and muscle weakness. These symptoms have occurred in distinct episodes over the past several years, each lasting for a few weeks before resolving, sometimes leaving residual deficits. What is the BEST initial diagnostic test to confirm the suspected diagnosis?

A patient with a known history of multiple sclerosis (MS) reports feeling significantly worse with exposure to heat. What physiological explanation BEST explains this phenomenon?