Neurology Flashcards
Diagnosis
3-4 month old infant with:
- enlarged abdomen
- lactic acidosis
- hypoglycemia
- doll-like face (fat cheeks)
- thin extremities
- short stature
- hyperuricemia
- hyperlipidemia
Von-Gierkes’ disease (type I glycogen storage disease)
Caused by a glucose-6 phosphatase deficiency in the liver, kidney and intestinal mucosa. The enlarged abdomen is due to an enlarged kidney and liver. Hypoglycemia may result in seizures.
Treatment:
Narcolepsy
- Stimulants to reduce daytime somnolence (i.e. modafinil, armodafinil, methylphenidate, dextroamphetamine, methamphetamine)
- sodium oxybate to reduce cataplexy
- Sleep schedule
- Avoid alcohol and drugs that cause drowsiness
Excessive daytime sleepiness + cataplexy
Narcolepsy
Treatment:
Amyotrophic lateral sclerosis
Riluzole
MA: glutamate inhibitor
Riluzole does not arrest the underlying pathological process, but it does prolong (1) survival & (2) time to tracheotomy.
Side effects: dizziness, nausea, weight loss, elevated liver enzymes, skeletal weakness
Which drug(s) is/are associated with fetal hydantoin syndrome?
Phenytoin, carbemazepine & many other AEDs
Clinical Manifestation:
- small body size
- microcephaly
- hypoplasia of the distal phalanges of the fingers and toes
- nail hypoplasia
- excess hair (hirsutism)
- cleft palate
- rib anomalies
Diagnosis:
Your patient experiences loss of consciousness followed by a lucid interval after a fall. Upon arrival to the ER the patient slowly becomes confused and consciousness deteriorates again. Head CT shows a bioconvex hematoma.
Acute epidural hematoma
LOC –> lucid –> declining consciousness + bioconvex hematoma
Clinical Manifestation: may include an ipsilateral dilated pupil caused by CN III compression
Tx: Craniotomy if the patient has focal neurologic signs or risk for brain herniation/injury.
Clinical Manifestations:
Alcoholic cerebellar degeneration
- Gait instability
- Truncal ataxia
- Intention tremor
- Hypotonia –> pendulum like swing after stimulation of patellar tendon
- Difficulty with rapid alternating movements
How is Creutzfeldt-Jakob disease differentiated from other types of dementia?
- CJD is rapidly progressive
- Prominent myoclonus
- 14-3-3 proteins in the cerebrospinal fluid (characteristic but not required for diagnosis)
Diagnosis:
Electroencephalogram shows bi- or tri-phasic sharp wave complexes in a patient with rapidly progressive dementia
Creutzfeldt-Jakob disease
Treatment:
Wernicke encephalopathy
Thiamine
Also, thiamine + glucose
Criteria necessary to diagnose a febrile seizure
- Age 6 months –> 6 years
- Temperature greater than or equal to 38 C (100.4 F)
- No previous history of afebrile seizures
- No CNS infection
- No acute systemic metabolic cause of seizures
Treatment:
Febrile seizure
- Abortive therapy if seizure lasts for 5 minutes or longer
2. Reassurance the prognosis for febrile seizures if very good, less than 5% of kids go one to develop epilepsy.
What are the characteristics of a high-grade astrocytoma in CT/MRI images?
- Heterogenous
2. Serpinginous
Clinical Manifestation:
CNS lesion affecting cortical innervation of the facial nucleus
Contralateral lower facial weakness with sparing of the forehead.
Facial weakness may manifests as: (1) loss of nasolabial folds, (2) drooping of the corner of the mouth, (3) loss of taste over the anterior 2/3 of the tongue (4) hyperacusis (5) decreased tearing.
Clinical Manifestation:
Facial nerve paralysis due to a lesion below the pons
(1) Decreased brow movements
(2) Inability to close the eye
(3) Eyelid drooping
(4) Loss of nasolabial fold
(5) Mouth drooping
(6) Decreased tearing
(7) Decreased taste over the anterior 2/3 of the tongue
(8) Hyperacusis
Which type of dementia is associated with early, mild memory loss and stepwise decline in executive dysfunction?
Vascular dementia
Vascular dementia may also be associated with findings of cerebral infarction and deep white matter changes on CT/MRI.
- Alzheimer dementia –> Early memory loss, late personality changes, spatial disorientation
- Frontotemporal dementia –> Early personality change (apathy, disinhibition, compulsions), frontotemporal atrophy on imaging
- Lewy body dementia –> Visual hallucinations, spontaneous parkinsonism, fluctuating cognition
- Normal pressure hydrocephalus –> Early ataxia, urinary incontinence, dilated ventricles on imaging
- Prion Disease–> Rapidly progressive, myoclonus/seizures, behavioral changes
What enzyme is deficient in Lesch-Nyhan syndrome?
Hypoxanthine-guanine phosphoribosyl transferase (HPRT)
This leads to a build up of uric acid resulting in: (1) self-mutilation (2) gout (3) mental retardation (4) dystonia (5) choreoathetosis (6) spasticity (7) gouty arthritis (8) tophus formation.
If you see a young child with gout, what enzyme deficiency should be on your differential?
Lesch-Nyhan syndrome
Deficiency of HPRT results in uric acid excess. Generally gout is seen in individuals above 50 years of age.
Diagnosis:
CSF results in a patient with Multiple Sclerosis (MS)
- Oligoclonal bands (present in 85-90% of MS cases)
Normal pressure, total protein and cell count.
NOTE: Although the total protein is normal, there is a disporprotionate ammount of immunoglobulin G proteins. Also, IgG elevation is not diagnostic for MS. It can be elevated in (1) neuropathies (2) chronic CNS infections and (3) viral syndromes. The IgG test also has a 8% false positive rate.
Clinical Manifestation:
Transtentorial (uncal) herniation
Ipsilateral findings:
- Ptosis, strabisumus and mydriasis
- Hemiparesis
Controlateral findings:
3. Hemaniopsia (vision loss)
General findings:
4. altered mental status –> due to compression of the reticular formation
Localize the lesion:
Pt has (1) difficulty speaking (2) right sided weakness & (3) inability writing & inability to repeat commands
Dominant frontal lobe
The ability to speak and write language is controlled by the dominant (usually left hemisphere). The front lobe contains the primary motor cortex necessary to produce movement on the right side. Also, the supplementary motor cortex helps with motor function and results in apraxia if damaged.
How do you differentiate an acute demyelinating plaque of multiple sclerosis from a transient ischemic attack (TIA)?
MS flare lasts for days to weeks; TIA symptoms last <24 hours
Initial Treatment:
Transient ischemic attack (TIA)
- Modify risk factors
- Aspirin + Statin
- Improve blood pressure control
What lobe of the brain is most often affected in Herpes simplex virus (HSV) encephalitis?
Temporal lobe
Suspect HSV encephalitis in patients presenting with new onset seizures.
What CSF findings do you suspect in a patient with HSV encephalitis?
- lymphocytic pleocytosis
- increased number or RBCs
- elevated protein
What is the gold standard for diagnosing HSV encephalitis?
HSV polymerase chain reaction analysis
When should you suspect multiple sclerosis in a patient with trigeminal neuralgia?
If trigeminal neuralgia presents bilaterally, suspect multiple sclerosis.
Diagnose:
Trigeminal neuralgia
Recurrent and sudden onset severe, stabbing pain in the V2 & V3 distribution of the trigeminal nerve
What is the characteristic gait finding in Parkinsonism?
Shuffling gait: Patient appears to be chasing their center of gravity.
Pathogenesis:
Parkinson’s
- Overactivity of cholinergic neurons in the substantia nigra
- Underactivity of dopaminergic neurons in the substantia nigra
What is the initial diagnostic test of choice when evaluating a suspected stroke?
non-contrast CT
Hemorrhagic strokes appear immediately on non-con CT as white, hyperdense regions. Ischemic strokes do not become evident (hypodense) until >24 hours after the event.
What is the initial diagnostic workup of a first-time seizure?
- basic blood test (serum electrolytes, glucose, calcium, magnesium, CBC, renal and liver function test)
- Urine toxicology: To rule out metabolic and toxic causes
- Neuroimaging (if unprovoked)
- EEG
Which neuromuscular junction syndrome is associate with underlying malignancy?
Lambert-Eaton myasthenic syndrome is frequently associated with malignancy (eg, small cell lung cancer).
Pathogenesis:
Lambert-Eaton myasthenic syndrome
Autoantibodies directed against the voltage-gated calcium channels in the presynaptic motor nerve terminal
What are the clinical findings in Lambert-Eaton myasthenic syndrome?
- Symmetrical proximal muscle weakness
2. Depressed deep tendon reflexes
What are the clinical findings of late neurosyphilis?
- Tabes dorsalis (sensory ataxia, lancinating pains, reduced/absent deep tendon reflexes)
2 Argyll Robertson pupils (pupils constrict with accommodation but not with light)
Treatment:
Neurosyphilis
IV penicillin
Diagnose:
Postconcussive syndrome
- Headache
- Confusion
- Amnesia
- Difficulty concentrating or multitasking
- Vertigo
- Mood alteration
- Sleep disturbance
- Anxiety
Symptoms resolve within weeks to months, or greater than or equal to 6 months in persistent cases.
Treatment:
Postconcussive syndrome
Symptomatic treatment will usually resolve within weeks to months; or >/= 6 months in persistent cases.
What clinical syndrome might you expect hours to days after a traumatic brain injury (TBI)?
Postconcussive syndrome
What teratogenic effects are associated with phenytoin?
fetal hydantoin syndrome
How do you discontinue phenytoin in a women of childbearing age considering pregnancy?
Slow taper! Rapid withdrawal may result in seizure recurrence.
Which area in the brain is involved in a patient presenting with hemi-neglect syndrome?
Right (non-dominant) parietal lobe
How does hemi-neglect syndrome manifest?
Patient will ignore the left side of a space.
Clinical Manifestation:
Vitamin B12 deficiency
- Macrocytic anemia
- Subacute combined degeneration (weakness, spastic paresis, +Babinski, diminished light touch and vibration and progressive tingling and numbness)
What is the earliest and most prominent impairment in a patient presenting with Alzheimer disease?
Memory impairment
What is the differential diagnosis for a patient with dementia and memory impairment?
- Alzheimer disease
- Lewy body dementia
- Frontotemporal dementia
- Vascular dementia
- Normal pressure hydrocephalus
What diagnosis should you always suspect in any IV drug user presenting with fever and a new cardiac murmur?
Infective endocarditis
What clinical sequela is associated with infective endocarditis?
Septic embolic (eg dislodgement of infected vegetations) leading to:
- Cerebral ischemic infarction
- Cerebral abscess
- Bacterial meningitis
- Renal injury
Clinical Manifestation:
Parkinson
- Resting tremor
- Rigidity
- Bradykinesia
At least two of these signs on physical exam is grounds for a clinical diagnosis of Parkinson disease.
What patient population most commonly develop central cord syndrome?
Elderly patients with spondylosis.
MA: hyperextension injury
Clinical Manifestation:
Central cord syndrome
- Upper extremity weakness > Lower extremity weakness
2. Loss of pain and temperature sensation
What is syringomyelia?
Fluid filled cavity located in the cervical and thoracic spinal cord.
What other disorder is commonly associated with syringomyelia?
Arnold Chiari malformation type 1
Cerebellum, but NOT brainstem, protrudes through the foramen magnum.
Clinical Manifestation:
Botulism
- Bilateral cranial neuropathies
- Symmetric descending muscle weakness
Occurring within 36 hours of ingestion of improperly canned fruits/vegetables and cured fish.
Mechanism of Action:
Subdural hematoma
- Head Trauma (typically)
2. Rupture of bridging veins
What are the risk factors for the subdural hematoma?
- Advanced age
- Chronic alcoholism (leading to brain atrophy)
- Anticoagulant use
How does an acute subdural hematoma appear on non-contrast CT head?
Crescent-shaped hyper density that crosses the suture lines
Diagnosis:
- Unilateral headache
- Pusling or throbbing quality
- Associated with N/V and photophobia
Migraine
Treatment:
Migraine refractory to abortive treatment
Prophylactic Tx:
- Topiramate
- Beta-blockers
- Amitryptyline
PPX treatment is also indicated for patients with frequent attacks.
Diagnose:
- Fluctuating, fatigable muscle weakness: worse with repetitive motion, improves with rest
- Diplopia
- Ptosis
- Dysarthria
- Dysphagia
Myasthenia gravis
What are the common presenting symptoms in patients with myasthenia gravis?
- Ocular dysfunction (diplopia, ptosis)
2. Bulbar dysfunction (dysarthria, dysphagia)
What initial workup is required to differentiate between a diagnosis of mild cognitive impairment, dementia and psuedodementia?
Neurocognitive testing (eg, MMSE, geriatric depression scale)
Diagnose:
- Gradual memory loss
- Language difficulties
- Apraxia
- Impaired judgment
- Personality and behavioral changes
Alzheimer’s disease
What does brain imaging reveal in patients with Alzheimer’s disease?
Generalized cortical atrophy
Where is the most common site of ulnar nerve entrapment?
The elbow.
The ulnar nerve is medial to the epicondylar groove.
How does multiple sclerosis appear on T2 weighted imaging?
Multifocal ovoid, subcortical white matter lesions.
Most common locations: periventricular,
