Neurology Flashcards
What medication(s) are shown to modify the disease process of ALS?
Riluzole
Glutamate antagonist. Prolongs tracheostomy-free survival
ALS is associated with what findings on nerve conduction studies or electromyography?
Upper and/or lower motor neuron conduction delay
Normal sensory nerve conduction
How is ALS diagnosed?
Clinical or electrophysiological evidence of progressive LMN and UMN degeneration
(No gold standard diagnostic test. CPK often elevated. MRI/CT is done to exclude other conditions.)
Spastic weakness is associated with dysfunction of what nerve type?
Upper motor neuron
Flaccid weakness is associated with dysfunction of what nerve type?
Lower motor neuron
What is the first diagnostic test used for suspected Charcot-Marie-Tooth disease?
Nerve conduction studies
Biopsy and DNA testing is used, although not all CMT genes are known.
Charcot-Marie-Tooth disease is associated with what findings on nerve conduction studies?
Uniform slowing of all motor and sensory nerves
Diagnosis: neurologic disorder with high foot arch and claw toes
Charcot-Marie-Tooth disease
What main medication(s) are beneficial for symptomatic control of peripheral neuropathy?
Gabapentin
Pregabalin
What medication(s) improve recovery times for Bell palsy?
Corticosteroids
What is the most common complication of Bell palsy?
Corneal abrasion/ulcer
From severe dry eye and scratching due to inability to blink. Prevent with lubricant drops and eye patch/tape.
How is corneal ulceration prevented in the setting of Bell palsy?
Eyedrops, patch/tape
Guillain-Barre Syndrome is associated with what findings on CSF studies?
Elevated CSF protein level
normal CSF cell counts
Diagnosis: unilateral facial droop with weakness of upper and lower facial muscles
Bell Palsy
Diagnosis: unilateral facial droop with weakness of lower facial muscles and preservation of upper facial muscles
CVA/TIA
Diagnosis: elevated CSF protein with normal CSF cell counts
Guillain-Barre syndrome
albuminocytologic dissociation
Diagnosis: acute ascending flaccid weakness
Guillain-Barre syndrome
Diagnosis: chronic acquired progressive upper and lower motor neuron dysfunction with preserved sensation
ALS
Diagnosis: hereditary progressive sensory and motor neuron dysfunction, beginning with distal extremities
Charcot-Marie-Tooth disease
What is the main feared complication of Guillain-Barre syndrome?
Respiratory failure
(Diaphragmatic paralysis. One third of GBS patients require ICU admission for this. Additional severe complications include hypotension/arrhythmia due to autonomic instability.)
What is the main treatment for Guillain-Barre syndrome?
IVIG
Plasma exchange
True or false: steroids have a role in the treatment of Bell Palsy
True
speeds recovery times
True or false: steroids have a role in the treatment of Guillain-Barre syndrome
False
What is the first step in diagnosis of suspected myasthenia gravis?
Anti-acetylcholine receptor antibody (AChR-Ab) titer
Does not correlate with disease severity. EMG is more sensitive but more invasive.
What is the most sensitive diagnostic test for myasthenia gravis?
Electromyography (EMG)
Diagnosis: nerve study with diminishing signals when repetitive stimulation applied
Myasthenia gravis
Diagnosis: nerve study with increasing signals when repetitive stimulation applied
Lambert-Eaton myasthenic syndrome
Small-cell lung cancer
Diagnosis of myasthenia gravis requires additional imaging to check for what concurrent condition?
Thymoma
XR/CT/MRI
Thymoma is associated with what neurologic condition?
Myasthenia gravis
What is the initial medical therapy for newly-diagnosed myasthenia gravis?
Pyridostimgine or neostigmine
AChE inhibitor
Treatment: acute severe weakness in a patient with known myasthenia gravis
IVIG or plasmapharesis
Myesthenic crisis
In a myasthenia gravis patient with acute severe weakness, what features are concerning for cholinergic crisis?
Recent increase in pyridostigmine dosage
Cholinergic signs: miosis, bradycardia, etc.
(Cholinergic crisis is very rare compared to myesthenic crisis)
Treatment: acute severe weakness and bradycardia in a patient with known myasthenia gravis who was known to have recently increasing pyridostigmine dosage
Atropine
Cholinergic crisis
True or false: thymectomy is generally indicated for patients with thymoma and myasthenia gravis
True
It is also indicated in patients age 10-55 with myasthenia gravis even WITHOUT thymoma
True or false: steroids have a role in the treatment of myasthenia gravis
True
used in patients that do not respond sufficiently to AChE inhibitors and thymectomy
Diagnosis: acute weakness in patient with myasthenia gravis, transiently improved with edrophonium
Myasthenic crisis
Edrophonium: short-acting AChE inhibitor
Diagnosis: acute weakness in patient with myasthenia gravis, transiently worsened with edrophonium
Cholinergic crisis
What is the gold-standard diagnostic test for craniopharyngioma?
MRI brain W/WO
Calcified suprasellar lesion
Diagnosis: child with chronic headache, visual field deficit, and growth failure
Craniopharyngioma
A growing craniopharyngioma will compress surrounding structures, causing what secondary deficits?
Optic nerve dysfunction (visual field deficit)
Hypopituitarism
What are the main categories of Alzheimer disease medications, by mechanism?
Cholinesterase inhibitors
NMDA antagonists
What are the main cholinesterase inhibitors used in Alzheimer disease?
Donepezil
Rivastigmine
Galantamine
What are the main NMDA antagonists used in Alzheimer disease?
Memantine
How is Alzheimer disease diagnosed?
Diagnosis of exclusion
First step is to rule out alternate diagnoses including B12 deficiency, hypothyroidism, syphilis, HIV, depression
Diagnosis: progressive dementia with hallucinations and parkinsonian motor dysfunction
Dementia with Lewy Bodies
What medications are used to treat dementia with Lewy Bodies?
For dementia/psychiatric disturbance: donepezil, galantamine, rivastigmine, memantine
For motor disturbance: levodopa/carbidopa
Diagnosis: rapidly progressive dementia with myoclonic jerks, spasticity
Creutzfeldt-Jakob disease
What is the gold-standard diagnostic test for Creutzfeldt-Jakob disease?
Tonsil/lymph or brain biopsy
What is the most common chronic complication of bacterial meningitis?
Hearing loss
Others: intellectual disability, cerebral palsy, seizures
What is the first step in management of a patient with acute fever, headache, and nuchal rigidity?
Early antibiotics: ceftriaxone, vancomycin ± acyclovir
Do not delay antibiotics to perform lumbar puncture
How would a finding of focal weakness or numbness on neurologic exam affect the management of a patient with suspected meningitis?
Head CT is required prior to lumbar puncture
if structural lesion is present, LP may cause herniation and death
Diagnosis: IV drug abuser with fever, back pain and vertebral tenderness
Epidural abscess
What is the gold-standard diagnostic test for epidural abscess?
MRI
ESR/CRP not specific
Diagnosis: acute lower extremity weakness with saddle numbness and incontinence
Cauda equina syndrome
What is the gold-standard diagnostic test for cauda equina syndrome?
MRI
How is cauda equina syndrome treated?
Steroids + surgical decompression + treatment of underlying cause (infection or neoplasm)
(Antibiotics for infectious causes. Radiation/chemo for neoplastic causes. Discectomy if related to herniated disc)
(Surgical decompression ideally performed within 6 hours of onset)
