Medicine
Neurology
A patient with Wernicke encephalopathy should receive which vitamin urgently, ideally before glucose in a malnourished patient?
A. Thiamine
B. Vitamin K
C. Vitamin D
D. Folate only
Correct Answer: A
Thiamine replacement is essential in suspected Wernicke encephalopathy, and should precede or accompany glucose in at-risk malnourished patients.
Medicine
Neurology
A patient has progressive asymmetric weakness, fasciculations, hyperreflexia and no sensory loss. What is the most likely diagnosis?
A. Amyotrophic lateral sclerosis
B. Multiple sclerosis
C. Guillain-Barré syndrome
D. Myopathy
Correct Answer: A
Combined upper and lower motor neuron signs without sensory loss strongly suggest ALS.
Medicine
Neurology
A patient with suspected bacterial meningitis has papilledema and focal neurologic deficits. What should be done before lumbar puncture?
A. Brain imaging
B. No imaging is ever needed
C. EEG
D. Carotid Doppler only
Correct Answer: A
Papilledema and focal deficits raise concern for intracranial mass effect, so imaging is indicated before lumbar puncture.
Medicine
Neurology
A patient has vertigo, dysarthria, ipsilateral facial sensory loss and contralateral body sensory loss. Which circulation is most likely involved?
A. Posterior circulation
B. Anterior cerebral artery only
C. Middle cerebral artery only
D. Retinal artery only
Correct Answer: A
Crossed brainstem signs with vertigo and dysarthria point to a posterior circulation brainstem event.
Medicine
Neurology
A patient has unilateral facial weakness involving both forehead and lower face with no limb deficits. What is the most likely localization?
A. Peripheral facial nerve palsy
B. Contralateral motor cortex lesion
C. Internal capsule stroke always
D. Cervical spinal cord lesion
Correct Answer: A
A lower motor neuron facial palsy affects both upper and lower facial muscles on the same side.
Medicine
Neurology
Which triad suggests normal-pressure hydrocephalus?
A. Gait impairment, cognitive decline and urinary incontinence
B. Fever, rash and arthritis
C. Ptosis, miosis and anhidrosis
D. Tremor, jaundice and diarrhea
Correct Answer: A
Normal-pressure hydrocephalus classically presents with gait dysfunction, cognitive impairment and urinary urgency/incontinence.
Medicine
Neurology
A 73-year-old has progressive memory loss affecting daily function, followed later by language and visuospatial impairment. What is the most likely dementia?
A. Alzheimer disease
B. Frontotemporal dementia in all cases
C. Normal-pressure hydrocephalus only
D. Delirium
Correct Answer: A
Alzheimer disease commonly begins with progressive episodic memory impairment and later affects multiple cognitive domains.
Medicine
Neurology
A patient has a generalized convulsive seizure lasting 7 minutes. What is the first-line acute medication?
A. IV/IM benzodiazepine
B. Oral phenytoin only
C. Aspirin
D. Haloperidol
Correct Answer: A
Convulsive status epilepticus is treated immediately with a benzodiazepine, followed by longer-acting antiseizure therapy if needed.
Medicine
Neurology
A patient has recurrent episodes of optic neuritis and sensory deficits separated in time and location. Which disease is most likely?
A. Multiple sclerosis
B. Amyotrophic lateral sclerosis
C. Myasthenia gravis
D. Peripheral neuropathy from diabetes only
Correct Answer: A
Neurologic deficits disseminated in time and space, including optic neuritis, are characteristic of multiple sclerosis.
Medicine
Neurology
A patient with Parkinson disease has resting tremor, rigidity and bradykinesia. Loss of neurons occurs primarily in which structure?
A. Substantia nigra pars compacta
B. Hippocampus
C. Caudate only
D. Cerebellar vermis
Correct Answer: A
Parkinson disease is associated with degeneration of dopaminergic neurons in the substantia nigra pars compacta.
Medicine
Neurology
A woman has fluctuating ptosis and diplopia that worsen late in the day. What is the most likely diagnosis?
A. Myasthenia gravis
B. Lambert-Eaton syndrome
C. Multiple sclerosis
D. Bell palsy
Correct Answer: A
Fatigable ocular weakness is a classic presentation of myasthenia gravis.
Medicine
Neurology
Which cerebrospinal fluid pattern supports Guillain-Barré syndrome?
A. High protein with relatively few cells
B. Low protein with neutrophilia
C. Very low glucose with lymphocytes only
D. Many malignant cells in all cases
Correct Answer: A
Albuminocytologic dissociation—elevated CSF protein with a normal or mildly elevated cell count—is characteristic of GBS.
Medicine
Neurology
A patient has ascending weakness and areflexia 2 weeks after gastroenteritis. What is the most likely diagnosis?
A. Guillain-Barré syndrome
B. Myasthenia gravis
C. Multiple sclerosis
D. Polymyalgia rheumatica
Correct Answer: A
Acute progressive symmetric weakness with areflexia after infection is typical of Guillain-Barré syndrome.
Medicine
Neurology
A patient has sudden severe headache described as the worst of life. Noncontrast CT is negative but suspicion for subarachnoid hemorrhage remains high. What should be considered next?
A. Lumbar puncture or further vascular imaging according to timing and protocol
B. EEG only
C. Nerve conduction studies
D. Carotid massage
Correct Answer: A
If initial CT does not exclude subarachnoid hemorrhage and clinical suspicion remains high, additional diagnostic evaluation is required.
Medicine
Neurology
A patient develops sudden aphasia and right-sided weakness 90 minutes ago. CT shows no hemorrhage. What is the next key step in an otherwise eligible patient?
A. Assess urgently for reperfusion therapy
B. Delay treatment for 24 hours
C. Give antibiotics
D. Perform lumbar puncture first
Correct Answer: A
Acute ischemic stroke within the treatment window requires rapid assessment for intravenous thrombolysis and/or mechanical thrombectomy depending on findings and eligibility.
Medicine
Neurology
Which feature best distinguishes myasthenia gravis from a fixed structural muscle weakness?
A. Weakness is always maximal on waking and never changes
B. Sensory loss is the dominant feature
C. Reflexes are always absent
D. Weakness fluctuates and worsens with repeated use
Correct Answer: D
Fatigability and fluctuation are characteristic of neuromuscular-junction transmission failure.
Medicine
Neurology
Which complication or major adverse outcome is particularly associated with Myasthenia gravis?
A. Completed ischemic stroke
B. Hypoxic brain injury and rhabdomyolysis
C. Myasthenic respiratory crisis
D. Medication-overuse headache
Correct Answer: C
Respiratory and bulbar muscle weakness can cause life-threatening ventilatory failure.
Medicine
Neurology
A patient is diagnosed with Myasthenia gravis. Which is the most appropriate management principle?
A. Activate a stroke pathway and assess urgently for intravenous thrombolysis and/or mechanical thrombectomy when eligible
B. Use symptomatic acetylcholinesterase inhibition and individualized immunotherapy; treat myasthenic crisis in a monitored setting
C. Start rapid secondary stroke prevention based on etiology and bleeding risk
D. Give a benzodiazepine promptly followed by an appropriate longer-acting antiseizure medicine if seizures continue
Correct Answer: B
Treatment depends on severity and includes symptomatic, immunologic and thymus-directed strategies.
Medicine
Neurology
In a patient with suspected Myasthenia gravis, which investigation or diagnostic approach is most appropriate at this stage?
A. Acetylcholine-receptor antibody testing with electrodiagnostic studies when needed
B. Neurologic assessment including respiratory function with CSF and nerve-conduction studies when appropriate
C. Immediate noncontrast CT brain with rapid vascular assessment as indicated
D. Urgent brain and vascular evaluation plus cardiac rhythm assessment
Correct Answer: A
Autoantibody testing and neuromuscular transmission studies support the diagnosis.
Medicine
Neurology
A patient has fluctuating ptosis, diplopia and fatigable bulbar or limb weakness that worsens with repeated activity. What is the most likely diagnosis?
A. Parkinson disease
B. Guillain-Barré syndrome
C. Acute ischemic stroke
D. Myasthenia gravis
Correct Answer: D
Fluctuating fatigable weakness, especially ocular or bulbar, strongly suggests myasthenia gravis.