Neurology

Brain

Stroke

• H&P: Ischemic stroke risk factors parallel ASCVD, with addition of afib, endocarditis, mechanical valve, cardiac shunt. BE FAST. NIHSS. Permanent focal neurological deficits. Hemorrhagic stroke risk factors include hypertension, blood thinner, trauma, smoking, cancer. Different brain areas cause different stroke syndromes, see table below:

Stroke Syndromes

Artery	Syndrome
Lacunar (thalamus)	Pure sensory
Lacunar (internal capsule)	Pure motor
ACA	Contralateral leg weakness and sensory changes
Left MCA	Motor and sensory deficits in right arm, right face; aphasia
Right MCA	Motor and sensory deficits in left arm, left face; neglect
PCA (cerebellum, midbrain)	Homonymous hemianopsia; ataxia, poor coordination; Weber syndrome: ipsilateral CN III palsy and contralateral arm/leg weakness.
AICA (pons)	Ipsilateral limb ataxia and contralateral hemiplegia and loss of pain/temperature.
PICA (medulla)	Wallenberg syndrome (lateral medulla): nystagmus, vertigo, bulbar weakness (weak gag, dysphagia), Horner syndrome, loss of pain/temperature on ipsilateral face and contralateral body.

• Dx: Ischemic vs. Hemorrhagic. Can localize stroke based on symptoms. NCCT head to rule out hemorrhage; CTA, MRI to look for filling defects and ischemic injury; TTE, telemetry to evaluate for afib. Differential includes TIA, seizure.
• Tx: For ischemic stroke, give tPA within 4.5 hrs of symptom onset, otherwise hep gtt. If large occluding clot in major vessel, can do endovascular thrombectomy within 24 hrs. Contraindications to tPA include recent major surgery, history of hemorrhagic stroke, BP >180/105 mmHg, Plt < 100k, INR > 1.7, age < 18, intrabdominal bleed. Use caution in the 3-4.5 hr window in patients over 80, with DM, with a recent stroke, or on DOACs. Keep BP below 180/105 mmHg to avoid hemorrhagic transformation and avoid starting anticoagulation or anti platelet agents in the first 24 hrs after tPA. Prevention includes aspirin, statin, clopidogrel, blood pressure control, rate/rhythm control or ablation/Watchman for Afib, weight loss, diabetes control, and smoking cessation. Treatment for hemorrhagic stroke includes blood pressure control, surgical decompression (ventricular shunt or craniotomy).

Hematoma

Hematoma Types

	Vessel affected	History	Imaging
Epidural	Middle meningeal artery	High energy impact (e.g. MVA), Lucid interval	Lens shaped (high pressure arterial bleed compresses brain); doesn't cross suture lines (due to tethering of the dura to skull)
Subdural	Bridging veins	Old person or alcoholic with a fall (low energy)	Crescent shaped (low pressure venous bleed doesn't compress); may cross suture lines

Headache

Primary Headache Disorders

	H&P	Treatment	Prophylaxis
Migraine	F > M, throbbing, unilateral, aura, nausea, vomiting, photophobia, phonophobia, visual disturbances, family history, hours to days	NSAIDs, SQ triptans, CGRPs	AEDs (topiramate, valproate), Beta blockers (propranolol), Verapamil, low-dose TCAs (amitryptaline), zonisamide, botox, CGRPs
Cluster	M > F, sharp/stabbing, unilateral, retro-orbital, occurs at the same time each day, resolves quickly; exam reveals Horner syndrome, ipsilateral nasal congestion, conjunctival injection, lacrimation	100% O2, SQ triptans	AEDs (topiramate, valproate), Verapamil, lithium, steroids
Tension	dull/tight/pressure, bilateral, band-like, can extend into the neck and shoulders, triggered by stress, lasts up to 7 days	NSAIDs/APAP, massage, heat, relaxation	Avoid triggers

Secondary Headaches

Etiology	Presentation	Treatment
IIH	Can mimic migraine. Shows up in young, obese females, worse in the morning or with straining, can have papilledema on exam, elevated opening pressure on LP.	Acetazolamide (CA inhibitor decreases CSF production). Weight loss. Therapeutic LPs.
Tumor	Progressively worsening headache, worse in the morning. Can have focal neural deficits based on location.	Treat the cancer
Aneurysm	Can mimic migraine or SAH (if ruptured). May be seen on MRI, CTA.	May be able to coil or clip. Control BP.
Giant Cell Arteritis	Jaw claudication, pain with hair combing, ipsilateral vision loss, associated with RA, middle aged females. Temporal artery biopsy will show large vessel vasculitis with giant cells.	High dose steroids for 1-2 months. Don't wait for biopsy results.

Seizure

• H&P: Aura, can have a guttural cry at onset, symmetrical rhythmic convulsions, eyes remain open and deviate towards contralateral side during focal phase, lateral tongue lacerations, bowel/bladder incontinence, post-ictal state, post-seizure myalgias, can have transient weakness that mimics stroke (Todd paralysis)
• Dx: EEG. Categorize as focal (simple and complex) versus generalized (grand mal, petit mal, myoclonic, atonic). Juvenile myoclonic epilepsy (JME) has bilateral polyspike and slow wave EEG pattern in interictal period, myoclonus within 1 hr of waking, eventual progression to generalized tonic-clonic. Differential includes metabolic (hepatic encephalopathy, hyponatremia, hypomagnesemia, hypercalcemia, hypoglycemia), infectious (meningitis), intoxication (e.g. INH, Bupropion), EtOH withdrawal, neoplastic (brain tumor), vascular (aneurysm, stroke, hemorrhage, dissection). To evaluate for secondary causes, get CBC, BMP, LFTs, EtOH level, urine tox screen, AED levels, consider MRI in an adult with first-time seizure.
• Tx: AEDs (no first line agent, decide on a case-by-case basis). For status epilepticus, ABCs, give IV lorazepam, fosphenytoin if seizure persists, consider induced coma if all else fails.

Common AEDs

Drug	Spectrum/Indications	Side effects
Levetiracetam (Keppra)	Broad	Suicidality
Lamotrigine	Broad (also mood stabilizer)	SJS
Valproate	Broad (also JME)	Teratogenic, weight gain, hair loss, tremor, thrombocytopenia, pancreatitis, liver failure
Topiramate	Broad (also migraine ppx)	Cognitive impairment, weight loss, kidney stones
Carbamazepine	Narrow (focal, also trigeminal neuralgia)	Hyponatremia, pancytopenia
Phenytoin	Narrow (focal)	Gingival hyperplasia, bone demineralization, drug-induced lupus
Ethosuximide	Narrow (Abscence)	Sedation

Brain Death

• Dx: Must have SBP > 100, temp > 36°C, PaCO2 35-45, euvolemia, off all sedatives. If these conditions are met, test for brainstem reflexes: pupillary reflex (II, III), corneal reflex (V, VII), doll's eye reflex (III, IV, VI, VIII), and gag reflex (IX, X). If no brainstem reflexes, do apnea test: positive if no breathing when PaCO2 is 60 mmHg or 20 mmHg higher than patient's baseline. If apnea test is equivocal, can do four vessel angiography, EEG, or duplex US. Rule out secondary causes of coma (e.g. test for severe hypoglycemia)
• Tx: If two physicians agree on diagnosis, withdraw care (even in absence of family agreement)

Vertigo

• H&P: Differentiate between dizziness and lightheadedness. Peripheral and central vertigo present differently. Peripheral is positional, improves with eye fixation or closure, and central is more likely to have focal neural deficit.
• Dx: Nystagmus is rotary, unilateral, and fatigable in peripheral vertigo. In central vertigo, nystagmus is bilateral, sometimes vertical (highly specific). No headache, no CNS findings, mild ataxia, that lasts seconds (BPPV), minutes to hours (Ménière disease), more than a day (acute vestibular neuritis or labyrinthitis) or is variable duration (MS, chronic otitis media, acoustic neuroma). No headache, no CNS findings, moderate-severe ataxia with (VBI-vertebrobasilar insufficiency) or without (acute vestibular neuritis or labyrinthitis) falling.
• Tx: Treat underlying cause. For BPPV, the Epley maneuver, PT, antihistamines, benzos, and scopolamine can all help.

Spinal Cord

Spinal Cord Compression

• H&P: Low back or neck pain associated with limb weakness, sensory changes
• Dx: Sensory level, pain, weakness, numbness, or hyperreflexia below the level of compression, bowel/bladder incontinence and saddle anesthesia with cauda equina. Stat MRI. Differential includes tumor, disc herniation, osteomyelitis, epidural abscess, aneurysm, epidural/subdural hematoma, fracture
• Tx: Based on etiology. Don't give steroids for infection. May need neurosurgical decompression.

Spinal Stenosis

• H&P: Neurogenic claudication-low back pain that radiates to the buttock that is worse with spinal extension, walking downhill, and standing, better with walking downhill and leaning forward. Negative SLR.
• Dx: Degenerative changes and neuroforaminal narrowing on xray or MRI.
• Tx: NSAIDs, PT; multimodal, MNB, MND, ESI, laminectomy

Transverse Myelitis

• H&P: Inflammatory spinal cord process without compression but with weakness, numbness, and autonomic dysfunction below the level of the lesion.
• Dx: Bright area on MRI. Test CSF to rule out HSV, VZV, Lyme, MS.
• Tx: IV glucocorticoids. Plasma exchange.

Cord Syndromes

Spinal Cord Syndromes

Syndrome	Spinal Tracts Involved	Presentation
Syrinx	Spinothalamic decussation at ventral commissure, then corticospinal tracts	Loss of pain and temperature bilaterally at the level of the lesion, followed by weakness
Brown-Sequard	Hemi-cord dissection	Contralateral loss of pain and temperature, ipsilateral weakness and loss of light touch, vibration, and proprioception
Anterior	Spinothalamic, Corticospinal	UMN syndrome at the level of the lesion, loss of pain and temperature below the lesion
Posterior	Dorsal columns	Loss of light touch, vibration, and proprioception bilaterally below the level of the lesion

Anterior Horn Cells

Amyotrophic Lateral Sclerosis

• H&P: Idiopathic progressive destruction of upper and lower neurons with pure motor symptoms
• Dx: Combined UMN and LMN symptoms. EMG shows denervation and re-innervation, fasciculations.
• Tx: Riluzole, Edavarone

Nerve Roots

Radiculopathy

• H&P: Lower back or neck pain that radiates down the arms or legs.
• Dx: Acute onset pain is usually due to herniated disc. Chronic pain is usually due to spondylosis. Straight leg raise is positive in lumbar radiculopathy. Spurling maneuver (extend the neck and rotate to the side of the pain, then apply downward pressure) is positive in cervical radiculopathy.
• Tx: NSAIDs, PT, ESI, discectomy

Peripheral Nerves

Bell Palsy

• H&P: Unilateral, idiopathic facial weakness that self resolves.
• Dx: Clinical based on symptoms. Differentiate from stroke by looking for forehead and eyelid muscle involvement (spared in stroke).
• Tx: 1st line is steroids or waiting. Some people give acyclovir because of presumed association with VZV, but the evidence is lacking, and this remains controversial. Ophthalmic ointments or tape on eye to prevent corneal drying at night.

Carpal Tunnel Syndrome

• H&P: Numbness in the first 3.5 fingers due to repetitive motions.
• Dx: Reproduced with Tinel test, Phalen sign (wrist flexion). EMG shows nerve conduction deficit in median nerve.
• Tx: Splint and rest. Second-line is myofascial release surgery.

Neuromuscular Junction

Myasthenia Gravis

• H&P: Autoantibodies against AChR, presents with muscle weakness that worsens as the day progresses and with exercise and improves after sleep. Constantly used muscles (think postural muscles, diaphragm, and eyelids) are affected first. May have positive family history. May have thymoma.
• Dx: Look for ptosis that improves with ice pack test. Edrophonium test is positive. Single-fiber EMG shows unstable "jittery" baseline between APs. CT chest to look for thymoma.
• Tx: 1st line pyridostigmine. 2nd line steroids or immunomodulating meds (e.g. cyclosporine, azathioprine). Plasmapheresis or IVIG for myasthenia crisis. Thymectomy may reduce symptoms and exacerbations.

Lambert Eaton Myasthenia

• H&P: Autoantibodies against pre-synaptic voltage-gated Ca2+ channels. Improves with exercise.
• Dx: Negative edrophonium test. Associated with small-cell lung cancer.
• Tx: ...

Muscle

Muscular Dystrophy

• H&P: Proximal muscle weakness presenting at age 3-5, usually wheelchair bound early on, die in adolescence from respiratory failure.
• Dx: Toe walking, waddling gait, inability to climb stairs, Gower sign (pushing on legs with arms to straighten the trunk). Family history of X-linked disorder (Duchenne) with clinical symptoms or genetic testing in absence of family history. Look for absence of dystrophin gene. Elevated CK.
• Tx: Prednisone

Movement Disorders

Parkinson Disease

• H&P: Neurodegenerative progressive disease with motor symptoms (pill-rolling tremor, cogwheel rigidity, masked facies, stooped posture, shuffling gait, trouble initiating movements, soft speech) preceding neuropsychiatric symptoms (dementia, depression, psychosis). Caused by destruction of dopaminergic neurons in the substantia nigra.
• Dx: 2/4 TRAP symptoms (Tremor, Rigidity, Akinesia/Bradykinesia, Postural instability) one of which must be bradykinesia. Rule out other causes of Parkinsonism with MRI (e.g. drugs, vascular dementia, Lewy body dementia, multi system atrophy). Responds to carbidopa-levodopa.
• Tx: 1st line Carbidopa-Levodopa. DA agonists (Pramipexole, Bromocriptine, Ropinarole). Anti MAO (selegiline), anti COMT (etacapone), and anticholinergics (benztropine). Deep brain stimulator or pallidectomy.

Huntington Disease

• H&P: Choreiform movements, Parkinsonism, depression, psychosis. Shows up in mid-adulthood, fatal by mid 50s usually. Autosomal dominant.
• Dx: Family history + symptoms. Or genetic testing. MRI can show caudate atrophy.
• Tx: Supportive. Chorea: Benzodiazepines, valproate; Parkinsonism: Carbidopa-Levodopa; Depression: SSRIs; Psychosis: atypical antipsychotics

Autoimmune Disorders

Guillain-Barré syndrome

• H&P: Ascending paralysis typically following a respiratory or GI (e.g. campylobacter) infection. Also known as Acute Inflammatory Demyelinating Polyneuropathy (AIDP). Lasts 2-4 weeks. If it lasts > 8 weeks, think CIDP, C for Chronic. Hyporeflexia and parasthesias.
• Dx: Clinical. Can get EMG which shows slow conduction (due to demyelination). LP will show albuminocytologic dissociation (elevated protein, normal WBCs).
• Tx: Usually self resolves. Plasmapheresis or IVIG.

Multiple Sclerosis

• H&P: Demyelinating autoimmune disease that can be relapsing remitting, primary or secondary progressive, or progressive/relapsing.
• Dx: MRI shows periventricular fingerlike white matter lesions, LP shows oligoclonal bands, VEPs show delayed conduction
• Tx: 1st Copaxone, Glatiramer acetate, or interferon. 2nd Dimethyl fumarate, natalizumab, teriflunomide. Acute exacerbations use high-dose steroids. Symptom targeted treatment: SSRIs for depression; PT, stretching, massage, baclofen for spasticity; amantadine for fatigue; Gabapentin for neuropathic pain; timed voiding, fluid restriction, or oxybutynin for urinary incontinence

Neuropsychiatric Disorders

Dementia

• H&P:
• Dx: Differentiate from MCI (which has less severe symptoms that do not interfere with ADLs). Differential includes Alzheimer disease (most common), Parkinson disease, Lewy body dementia, frontotemporal dementia (Pick disease), vascular dementia, and Creutzfeld Jacob disease (prions). Check for reversible causes (TSH, B12, B6, urine tox screen, EtOH levels, infectious workups, depression screen).
• Tx: Based on etiology. AChE inhibitors: donepezil, rivastigmine, galantamine. Memantine (NMDA antagonist). Assisted living and social support.

Wernicke-Korsakoff Syndrome

• H&P: History of heavy EtOH use. Vitamin B1 (thiamine) deficiency.
• Dx: MRI shows atrophy of mammary bodies. EtOH level. Presents with ataxia, ophthalmoplegia, confusion, confabulation, retrograde amnesia. Differential includes NPH.
• Tx: High dose thiamine. Electrolyte repletion. Multivitamin. CIWA protocol for EtOH withdrawal.

Missed on UWorld

• SNRI (venlafaxine), SSRIs, or TCAs can be used for narcolepsy associated cataplexy (loss of muscle tone associated with strong emotions)