Neurology Flashcards
Parkinson disease characteristics
At least 2 of the following: Bradykinesia, rigidity, resting tremor, postural reflex abnormality
Parkinson disease brain involvement
degeneration of dopaminergic neurons in the substantia nigra of the midbrain
Parkinson disease general characteristics
asymmetric signs and symptoms, diminished sense of small, constipation, acting out dreams; these symptoms may precede motor symptoms by years.
May have frequent falls
If dementia in the first year concern got dementia with lewy bodies
Cutaneous finding in parkinsons disease
seborrheic dermatitis
Multiple system atrophy
severe orthostatic hypotension and ataxia
MRI shows “necrosis” of the putamen and cerebellar atrophy
Progressive supranuclear palsy
Unexplained falls backwards, inability to move eyes vertically, parkinonian features
Dementia with lewy bodies
early dementia, parkinsonism, hallucinations
Medication induced parkinsonism
antiemetics (prochlorperazine, metoclopramide), antipsychotics (haloperidol), reserpine, lithium, methyldopa
Distinguished from Parkinson disease by symmetry of symptoms and absence of typical nonmotor features
Parkinsons treatment
Patients <65 start pramipexole and ropinirole (avoid dyskinesias and wearing off effect)
>65 Levodopa + Carbidopa to prevent peripheral conversion of levodpa to dopamine
Deep brain stimulation if patient has motor benefit from levodopa but medication adverse effects
Essential tremor manifestations
slowly progressive or stable over time
bilateral postural or kinetic tremor
improves with alcohol
family history positive in 50%
Rigidity and resting tremor are NOT features
Patients <40 with essential tremor should be screened for Wilson disease with serum ceruloplasmin and 24-hour urine copper measurements
Essential tremor treatment
propranolol, primidone, topiramate
Huntington disease characteristics
autosomal dominant
most common neurodegenerative cause of generalized chorea
progressive dementia and psychiatric symptoms
Huntington disease treatment
tetrabenazine and deutetrabenazine
Drug induced dystonia manifestations
tardive dyskinesia with choreiform and dystonic craniofacial movements
can be caused by neuroleptic, antiemetic, serotoninergic medications
Drug induced dystonia treatment
stop the offending drug
valbenazine, clonazepam, tetrabenazine, anticholinergic agents, clozapine
Cervical dystonia (torticollis)
Cervical muscle contractions resulting in abnormal posture of head and neck
Cervical dystonia (torticollis) treatment
Botulinum toxin
Tourette syndrome
childhood onset
multiple complex motor tics
presence of vocal tics
tourette syndrome treatment
cognitive behavioral therapy, reassurance
First-line agents used to treat Tourette syndrome when the associated tics interfere with education, daily function, or work are clonidine, guanfacine, topiramate, and tetrabenazine.
Second-line treatments include antipsychotic agents (such as haloperidol), but their benefit should be weighed against risk of tardive dyskinesia.
Myoclonus
Rapid, shock-like, jerky movements of isolated body parts
underlying metabolic disorder, serotonin syndrome, postanoxic, creutzfield jakob disease, corticobasal degeneration
Multiple sclerosis acute treatment
Acute: IV methlypredisolone followed by oral steroids
Treat fever/look for infection before starting steroids (could be pseudorelapse)
Multiple sclerosis chronic treatment
interferon beta or glatiramer acetate, teriflunomide could also be effective
Add vitamin D to treatment with interferon beta, reduced accumulation of MRI lesions. Recommended for all MS patients
Interferon agents contraindicated in patients with liver disease or depression
Clinical courses of MS
Relapsing-remitting: dysfunction lasting weeks then improving, accumulation of disability
Secondary progressive disease: No more relapses, now progressive disability
Primary progressive disease: progressive disability from time of onset
Droxidopa
approved for management of neurogenic orthostatic hypotension in Parkinson disease
Dystonic tremor
occurs both at rest and with action and is characterized by associated dystonic posturing and the presence of a null point at which change in the position of the affected limb resolves the tremor.
The null point is the position at which the trajectories of the forces caused by dystonic coactivation of agonist and antagonist muscles neutralize each other, which leads to resolution of the tremor.
the action component of tremor has task specificity (worse with use of scissors but spares the handwriting).
Cerebellar tremor
characterized by increasing tremor amplitude as the limb approaches the target (terminal intention tremor) and the presence of associated cerebellar symptoms
Parkinsonian tremor
prominent at rest
can reemerge after a brief delay when the arms are held in an outstretched position
Rubral tremor
caused by focal injury to cerebellar outflow pathways and is characterized by a coarse tremor that is present at rest but most severe during action.
prominent proximal component and interferes with various actions, such as feeding, typing, and writing, in a nonselective way.
MRI of the brain reveal a focal causative lesion
Psychosis in parkinsons disease
Pimavanserin, a nondopaminergic atypical antipsychotic agent and selective serotonin 5-hydroxytryptamine receptor 2A inverse agonist, is the only FDA-approved medication for Parkinson psychosis.
Quetiapine and clozapine also can be considered in this setting
Other atypical antipsychotic agents (including aripiprazole, risperidone, and olanzapine) and all typical (first-generation) antipsychotic agents should be avoided.
Periodic limb movements of sleep
characterized by periodic leg kicks, often with a stereotyped triple-flexion phenomenology that repeats periodically during sleep
can occur in otherwise healthy persons or be associated with sleep disorders, such as restless legs syndrome, sleep apnea, narcolepsy, and others
If another sleep disorder is present, treatment targeting the associated disorder also improves the periodic limb movements
If no associated sleep disorder is present treatment is only necessary if limb movements cause sleep fragmentation (brief arousals that occur during a sleep period). In the absence of such issues, no further testing or treatment is recommended.
Rapid eye movement (REM) sleep behavior disorder
A condition associated with loss of the muscle paralysis normally experienced during the REM dream phase of sleep and typically characterized by dream enactment behavior with complex movements and vocalizations
Clonazepam often is used to treat
Restless legs syndrome (RLS)
A common movement disorder characterized by discomforting sensations in the legs at rest or when falling asleep, an urge to move the legs, and immediate relief after moving the legs or walking.
Patients should be screened for iron deficiency and receive iron supplements in the presence of deficiency or even low-normal serum ferritin levels.
Neuromyelitis optica (Devic disease)
Recurrent episodes of myelitis and optic neuritis without the brain lesions typical of MS; NMO-IgG autoantibody may be present
Idiopathic transverse myelitis
Subacute onset of weakness, sensory changes, and bowel/bladder dysfunction, typically after a viral infection
Distinguished from MS by the presence of complete myelitis, no oligoclonal bands or elevated IgG index in the CSF, and no lesions on brain MRI
Vitamin B12 deficiency
Paresthesias, lower-extremity weakness, and gait instability
Findings may include paraparesis, vibration and position sense loss, and sensory ataxia.
Anemia may be absent
Check methylmalonic acid and homocysteine levels in patients with borderline B12 levels
Copper deficiency
Mimics vitamin B12 deficiency
May develop after bariatric surgery or from excessive zinc ingestion
Infarction of the spinal cord
Acute onset of flaccid paralysis or weakness and pinprick sensation loss below the level of the infarction
Potential causes include emboli, hypotension during cardiovascular/aortic surgery, and AV malformations
Amyotrophic Lateral Sclerosis Characteristics
The defining characteristic is the combination of upper motor neuron signs (e.g., hyperreflexia, spasticity, and extensor plantar response) coexistent with lower motor neuron findings (e.g., atrophy and fasciculation)
Sensory deficits are characteristically absent
Muscle weakness usually begins distally and asymmetrically, although 20% of patients have bulbar-onset ALS with difficulty speaking and swallowing
Fasciculations in the absence of associated muscle atrophy or weakness are not caused by ALS.
Weakness in the absence of fasciculations is not a result of ALS.
Amyotrophic Lateral Sclerosis Treatment
Riluzole may increase survival by about 3 months.
Begin noninvasive ventilatory support for patients with respiratory insufficiency.
Placement of a percutaneous endoscopic gastrostomy tube is indicated when weight loss or swallowing difficulty occurs.
Myasthenia Gravis Characteristics
MG is an autoimmune disease caused by antibodies directed against the acetylcholine receptor, which results in impaired neuromuscular transmission.
Characteristic findings of MG include:
- ptosis or diplopia (first manifestation in most patients)
- muscle weakness, including dysphagia and dyspnea
- positive anti–acetylcholine receptor antibody titer (found in 90% of patients; negative titer does not rule out MG)
- normal deep tendon reflexes and sensation
- decremental response to repetitive stimulation on EMG
Myasthenic crisis
may include rapidly progressive respiratory failure, can occur as part of the natural history of myasthenia or be triggered by infection, surgery, or medications.
Look for aminoglycosides, quinolones, magnesium, β-blockers, or calcium channel blockers as precipitants of myasthenic crisis.
Myasthenic crisis and refractory disease should be treated with plasmapheresis or IV immune globulin.
Pyridostigmine monotherapy should be avoided in those with myasthenic crisis because the drug increases respiratory secretions.
Myasthenia Gravis Tests to perform
Single-fiber EMG can establish the diagnosis.
Look for elevated serum TSH levels because of the association of MG with autoimmune thyroid disorders.
Perform CT of the chest to detect thymoma.
Myasthenia Gravis Treatment
Pyridostigmine is the initial therapy.
Thymectomy is indicated if a thymoma is found on imaging.
Myasthenic crisis and refractory disease should be treated with plasmapheresis or IV immune globulin.
Pyridostigmine monotherapy should be avoided in those with myasthenic crisis because the drug increases respiratory secretions.
Lambert-Eaton syndrome
involves progressive proximal weakness and diminished tendon reflexes that improve with repetitive movement of affected muscles.
Diagnosis is confirmed by detection of serum anti–voltage-gated calcium channel antibodies and the EMG finding of facilitation of motor response to rapid repetitive stimulation.
Most patients with this syndrome have an undetected malignancy, typically SCLC.
Myasthenia vs botulism
Botulism starts with cranial nerve involvement, including diplopia, dysphagia, and sluggish or nonreactive pupils, whereas the pupils are normal in MG.
Multiple sclerosis–related fatigue
The most common medications of this type used (off-label) in MS are modafinil, armodafinil, and amantadine. For fatigue that is refractory to these medications, amphetamine stimulants, such as methylphenidate, also can be considered.
Tardive dyskinesia
can be caused by exposure to dopamine-blocking agents, such as neuroleptic and antiemetic agents, and may persist for more than 6 months after removal of the offending medication or become permanent.
Pharmacologic treatment of tardive dyskinesia is often unsatisfactory, but options include clonazepam, tetrabenazine, valbenazine, anticholinergic agents, and clozapine.
Dalfampridine
significantly improved timed 25-foot walking speeds in patients with multiple sclerosis and gait impairment
rare adverse effect of seizures and should not be used in patients with kidney impairment, given the reduced clearance of the drug and resultant potentially higher rate of seizures.
Pseudobulbar affect
Pseudobulbar affect, a less common symptomatic manifestation of MS, can act as a significant impediment to social interaction in patients with MS. This symptom manifests as uncontrolled fits of laughter or crying that occur without distinct or appropriate triggers. A successful trial of the combination agent dextromethorphan-quinidine has led to FDA approval of the use of this pharmacotherapy for pseudobulbar affect in MS. It is not effective for improving or maintaining ambulation.
First line treatment for relapsing-remitting MS
Generally, self-injection medications (interferon beta or glatiramer acetate) are recommended as first-line agents for relapsing-remitting multiple sclerosis because of their favorable risk profiles.
First line treatment for progressive MS
Ocrelizumab is the only available therapy for primary progressive multiple sclerosis (MS)
mitoxantrone is the only FDA-approved therapy for secondary progressive MS
Natalizumab
Natalizumab is a highly effective treatment in multiple sclerosis that causes a two-thirds reduction in relapse rates, slowing of disability progression by approximately 40%, and a reduction in MRI activity of approximately 90% compared with placebo; it is typically limited to use as a second-line agent because of the risk of progressive multifocal leukoencephalopathy.
multiple sclerosis–associated spasticity
Muscle relaxants, such as baclofen, tizanidine, cyclobenzaprine, and the benzodiazepines, can help treat multiple sclerosis–associated spasticity due to corticospinal tract damage.
Peripheral neuropathy
may present with pain, paresthesias, weakness, or autonomic dysfunction
Neuropathies can be classified by:
- distribution of sensorimotor deficits (symmetric vs asymmetric, distal vs proximal, focal vs generalized)
- pathology (demyelinating vs axonal)
- size of nerve fibers involved (large vs small fibers)
- family history
- autonomic involvement
Mononeuropathy
isolated disorders affecting a single peripheral nerve
most frequently caused by nerve entrapment or compression (carpal tunnel syndrome)
Mononeuropathy multiplex
involves multiple noncontiguous peripheral nerves, either simultaneously or sequentially
This is often the result of a systemic disease. Consider vasculitis (especially if painful), lymphoma, amyloidosis, sarcoidosis, Lyme disease, HIV, leprosy, and diabetes”
Polyneuropathy
refers to a diffuse, generalized, and usually symmetric peripheral neuropathy
Polyneuropathy is often a manifestation of systemic disease (e.g., diabetes, vitamin B12 deficiency) or exposure to a toxin (e.g., alcohol) or medication (e.g., chemotherapy)
EMG and nerve conduction velocity can be helpful to characterize the type (axonal or demyelinating), severity, and distribution of the disease
Other routine tests include vitamin B12 level, SPEP, UPEP, ESR, and blood glucose level
Guillain-Barre Syndrome
Acute, ascending, areflexic paralysis and paresthesias
Often preceded by GI illness (usually Campylobacter infection)
CSF shows elevated protein and a normal cell count (albuminocytologic dissociation)
Treat with plasma exchange or IVIg
Chronic inflammatory demyelinating polyneuropathy
Progressive proximal motor and sensory neuropathy that evolves over months
Initial EMG and CSF findings similar to Guillain-Barré syndrome
Treat with prednisone, plasma exchange, or IVIg
Paraproteinemic Neuropathy
Symmetric distal sensory neuropathy in the setting of MGUS, multiple myeloma, amyloidosis, and cryoglobulinemia
Treat the underlying disorder
Peripheral neuropathy treatment
Only pregabalin, duloxetine, and tapentadol (extended release) are FDA approved for the treatment of painful neuropathy
Small cell lung cancer associated neurologic paraneoplastic syndromes
dementia, chorea, ataxia, brainstem encephalitis, and neuropathies, among others.
The antibodies associated with these syndromes include anti-Hu, anti-LGI1 (voltage-gated potassium channel), anti-CRMP5 antibodies and rarely the anti-NMDAR antibody.
Immune-mediated necrotizing myopathy
a form of statin myopathy that is associated with antibodies to hydroxymethylglutaryl coenzyme A reductase
biopsy evidence of muscle necrosis without inflammation
treatment with a glucocorticoid or other immunosuppressive agents can reverse the myopathy.
Idiopathic brachial plexopathy
characterized by subacute severe pain followed by resolution of pain and progressive weakness and atrophy involving the shoulder girdle and upper extremity muscles; this syndrome often is triggered by a preceding event, such as an infection or surgery
Diabetic mononeuropathy
Acute or subacute pain and paresthesia in a dermatomal pattern in the thoracic or abdominal region in a patient with diabetes mellitus and no evidence of herpes zoster is most likely due to diabetic mononeuropathy
Miller Fisher variant of Guillain-Barré syndrome
typically presents with subacute ataxia, areflexia, and ophthalmoplegia, with or without diffuse weakness
Antibodies to GQ1b (a ganglioside component of nerve) are present in more than 85% of patients. The patient’s findings are not compatible with the Miller Fisher variant.
