Neuropathies / Demyelinating Disorders Flashcards
Is Guillain Barre Syndrome (GBS) is an immune-mediate, demyelinating polyneuropathy, of the peripheral or central nervous system?
Peripheral Nervous System
What TWO symptoms/exam findings characterize GBS?
Muscle Weakness
Areflexia
Does GBS present as ascending or descending paralysis?
Where does it typically start?
Ascending paralysis
Typically starts in the hands/feet and spreads to the trunk
Which variant of GBS presents with flaccid paralysis?
What organism is associated with this condition?
What anti-bodies are present in this condition?
Acute Motor Axonal Neuropathy (AMAN)
C. jejuni
IgG Anti-GM
IgG anti-GD
Which variant of GBS presents with ascending paralysis and motor weakness?
Acute inflammatory demyelinating polyneuropathy (AIDP)
Ventilation is typically required in which variant of GBS?
Acute motor sensory axonal neuropathy (AMSAN)
The GBS variant, Miller-Fisher Syndrome, is associated with what symptoms?
What antibody is present?
Ataxia
Areflexia
Ophthalmoplegia
IgG Anti-GQ
Which GBS variant is the most common?
Acute inflammatory demyelinating polyneuropathy (AIDP)
AIDP is an auto-immune response against cells responsible for myelination.
What is the name of these cells?
Schwann Cells
AMAN attacks what portion of the nerve?
Nodes of Ranvier
T/F: Miller-Fischer Syndrome presents as descending paralysis
True
Which variant of GBS often is associated with a Babinski’s Sign?
Bickerstaff’s Brainstem Encephalitis
In GBS immune responses are directed against what TWO part of a nerve?
Myelin
Axon
Other than C. jejuni, what TWO infections were seen in GBs patients?
CMV
Epstein Barr
What cranial nerve may sometime be effected in GBS?
CN VII
What is typically the first symptom/presentation of GBS?
“Rubbery Legs”
Progressing to ascending paralysis
T/F: Immunizations can trigger GBS
True
Other than immunizations, what can trigger GBS?
Trauma
Surgery
Bone marrow transplant
What CA is associated with GBS?
Hodgkin Lymphoma
Are eye movement abnormalities common in GBS?
No
Only in Miller Fisher Syndrome
Will GBS patients often complain of pain?
Yes
Described as a dull aching pain in weakened muscles
How is GBS diagnosed initially?
Clinically
What might a LP show in a GBS patient?
Elevated protein
Normal WBCs
What study is useful in detecting active axonal damage in GBS?
Electromyography (EMG)
Abnormal conduction on EMG would confirm a diagnosis of ____________ polyneuropathy.
Demyelinating
What are the TWO mainstays for GBS treatment?
Plasma Exchange (Plasmaphoresis) IV IgG Therapy
What medications can be used to treat neuropathic pain in GBS?
Gabapentin
NSAIDs
Narcotics
T/F: Most GBS patients will not require some form of rehab
False
Many will
What is the most common disorder of neuromuscular transmission?
Myasthenia Gravis
T/F: Myasthenia Gravis is not an autoimmune disorder
False
It is
What are TWO characteristics of Myasthenia Gravis?
Distal-to-Proximal weakness
Fatigability of muscles
What Sx of the EYE may a myasthenia gravis patient have?
Ptosis
Diplopia
What FACIAL manifestation may a myasthenia gravis have?
Weak Chewing
Would a Myasthenia Gravis patient’s weakness be worse in the morning or throughout the day?
Throughout the day - Symptoms typically worsening with daily actives or exercise
What is the most serious Sx of Myasthenia Gravis?
Respiratory Distress
T/F: Thyroid disorders are found in 10% of Myasthenia Gravis patients
True
What antibody is found in 40% of MG patients who do not test positive for acetylcholine receptor antibodies?
Muscle-Specific Kinase (MuSk)
If a MG patient does not test positive for AchR or MuSK antibodies then they are considered what?
Seronegative MG
What is the name of the bedside test used to diagnosis Myasthenia Gravis?
Tensilon Test
Give Edrophonium
If symptoms improve = MG
Why is a CT or MRI ordered in MG evaluation?
15% of MG patients have a thymoma
What medications are used EARLY in MG?
Anticholinesterase:
Pyriogostigmine
Neostigmine
Ambenonium
This is because there are still acetylcholine receptors left
Other than anticholinesterase agents…..
What are additional pharmacological MG treatment options?
- Glucocorticoids
- Immunosuppression (Cyclosporine)
- Plasmaphoresis, IV IgG
What surgery may be preformed to treat MG?
Thymectomy
Does multiple sclerosis effect the peripheral or central nervous system?
Central Nervous System
Does MS more commonly effect men or women?
Women (Onsets around 30 y.o.)
What are the FOUR major pathological mechanisms of MS?
- Inflammation
- BBB Disruption
- Demyelination
- Axon Degeneration
MS involves a loss of what cells in the CNS responsible for myelination of axons?
Oligodendrocytes
Are MS plaques more common in the white or grey matter of the brain?
White Matter
Can MS plaques be found on the spinal cord?
Yes
Patients complaining of an electric shock down their spine with neck flexion wold be concerning for MS.
What is the name of the sign described above?
Lhermitte’s Sign
What cranial nerve is often involved in MS?
What disease of this nerve may be present?
CN II
Unilateral Optic Neuritis
Are sensory or motor symptoms more common in MS?
Does this affect the ascending or descending pathways in the spinal cord?
Ascending
T/F: Urinary urgency is a common complaint in MS
True
A 35 yo femal presents to your clinic complaining of diplopia and trouble seeing as well as she used to, feeling like she can’t walk well, and decreaesed sensation in her right arm that has gradually onset over the last few months.
On examination, he is found to be hyperreflexic, has horizontal nystagmus, and impaired sensation in her right arm.
What is you most concerning diagnosis?
What is the imaging study of choice in this patient and what might it show to confirm your Dx?
Multiple Sclerosis
MRI of the Brain: Irregular, Spotty Plaque formation (“Dawson’s Fingers”)
T/F: Almost 90% of MS patients are characterized as Progressive relapsing
False
90% of MS are characterized as Relapsing-Remitting
How are MS exacerbations treated?
High dose corticosteroids (Methylprednisone)
Plasmaphoresis may also be useful
What are examples of disease-modifying treatments of MS?
Beta-Interferons Glatiramar Acetate Methotrexate Mitoxantrone Cyclophosphamide
Does Amyotrophic Lateral Sclerosis (ALS) cause reversible or irreversible nerve damage?
Irreversible
Is ALS characterized by upper or lower motor neuron degeneration and death?
Upper Motor Neuron
Lower motor neuron deficits will develop late in the disease
Which spinal tract does ALS effect?
Corticospinal tract
What may you expect an ALS patient’s muscles to look like?
Atrophic
What is the pharmacological option for ALS treatment?
Riluzole
Typically ALS management involves treating the symptoms…..
What may need to be place if a patient develops severe dysphonia?
What may need to happen is a patient develops respiratory distress of compromised?
Dysphonia: PEG Tube
Respiratory: Tracheostomy, Ventilation
Are axonal or demyelinating neuropathies more common?
Axonal
How do mononeuropathies differ from polyneuropathies?
Mononeuropathies only effect a single nerve while polyneuropathies effect multiple nerves
What is more common acute, subacute, or chronic polyneuropathies?
Chronic Polyneuropathies (ie: Diabetic Neuropathy)
T/F: Bell’s Palsy is a polyneuropathy
False
It is a mononeuropathy
_______ is defined as increased pain from a stimulus that normally provokes pain
Hyperalgesia
________ is defined as diminished pain in response to a normally painful stimulus
Hypoalgesia
________ is defined as pain due to a stimulus that does not normally provoke pain
Allodynia
Neuronal degredation involves what part of the nerve?
Wallerian Degredation?
Segmental demyelination?
Neuronal: Nerve Bodies
Wallerian: Axon below the cell body
Segmental: Myelin Sheath
What is the most common hereditary neuropathy?
Charcot-Marie-Tooth Disease
What co-morbid condition is often closely associated with chronic axonal polyneuropathies?
Diabetes
T/F: Lyme Disease can result in axonal polyneuropathies
True
What percent of polyneuropathies are idiopathic?
25%
What is the “characteristic” presentation of polyneuropathies?
Of these symptoms is sensory or motor loss more common?
- Symmetric distal sensory loss
- Burning Sensation
- Pins and Needles
- Weakness
Sensory loss is most common
Are the longer or shorter axons effect first in chronic axonal polyneuropathies?
Longer Axons
What is the ‘classic’ distribution of sensory loss in chronic axonal polyneuropathy?
“Stocking and glove”
Hands and feet
What is a unique chronic complication involving the foot in chronic axonal neuropathies, particularly in diabetic patients.
These result due to micro fractures in the foot that don’t heal well.
Charcot Arthropathy
“Rocker-Bottom Foot”
Patients who present with a sudden onset of rapid sensory loss with or without pain after exposure to toxic chemicals would be considered to have a(n) __________ (acute/chronic) polyneuropathy.
Acute Polyneuropathy
Would you expect a patient with polyneuropathy to be hyperreflexic or hyporeflexic?
Hyporeflexic
How may you hear a patient’s legs described in more severe polyneuropathy resulting in muscle wasting?
“Inverted Champagne Bottle”
“Stork Leg Deformity”
What is the best diagnostic and initial study when evaluating polyneuropathy?
Electromyography (EMG)
What happens when you get a bladder infection?
…..Urine trouble
Would axonal loss lead to higher or lower magnitudes on nerve conduction studies?
Lower Amplitude
Would demyelination show an increase or decrease in conduction velocity?
Decrease in conduction velocity
Nerve biopsy can be used when polyneuropathy diagnosis remains unclear, although it can be low yield….
What is the preferred nerve and site for this?
Sural Nerve (ankle)
T/F: There are curative treatments for axonal polyneuropathy
False
There are no curative treatments, often you just treat the underling disease
What medication is often used to treat pain in neuropathies?
Gabapentin
Which area of the body do patients with diabetic neuropathies need to pay special attention to?
Their Feet
What neuralgia is characterized by brief episodes of unilateral shock like pains, that can follow a cranial nerve distribution?
Trigeminal Neuralgia
Trigeminal neuralgia is commonly due to idopathic neurovascular compression…..
However, it can also be associated with what virus?
Herpes Zoster
T/F: Pain in trigeminal neuralgia can typically onset with light touch stimulation
True
What are common triggers of trigeminal neuralgia?
Chewing Talking Brushing Teeth Cold Air Grimacing
Although trigeminal neuralgia is mostly diagnosed clinically…..
When would neuroimaging be warranted?
If the patient had obvious causes of pain
Ex: Herpes Zoster, Trauma
What medication is first line for trigeminal neuralgia treatment?
Carbamazepine
What surgical procedures are available to treat trigeminal neuralgia?
Microvascular Decompression
Ablation
Bell’s Palsy commonly affects what cranial nerve?
CN VII
Which virus is most commonly associated with Bell’s Palsy?
Herpes Zoster
What are classic presentations in Bell’s Palsy?
Facial Droop Unable to raise one eye brow Excessive Tearing Drooling Unable to close one eye Lack of nasal labial fold Nasal Flaring
What is the ‘mainstay’ of Bell’s Palsy treatment?
What can be added to this pharmacotherapy?
Prednisone
Antivirals (Acyclovir)
What ‘pain syndrome’ is described as pain that spreads beyond an area or trauma, injury, stroke, or MI?
Chronic Regional Pain Syndrome
Which is typically worse, the initial injury/trauma or the CRPS that follows?
The CRPS that follows
Is Type 1 or Type 2 CRPS more common?
Type 1
What fractures are commonly associated with CRPS, particularly in the hand?
Intra-articular radial-ulnar fractures
Ulnar styloid fractures
Is the upper extremity or the lower extremity more commonly effected by CRPS?
Upper Extremity
What are the THREE stages of CRPS?
- Burning Pain, Temperature sensory loss, and local edema
- Worsing edema, atrophy, skin thickening
- Worsening to limited ROM
T/F: Patients with CRPS often have allodynia
True
What bone disorder is often found in patients with CRPS?
Osteoporosis
CRPS is a diagnosis of _______.
Exclusion
What is the most beneficial step in treatment of CRPS?
Early Mobilization
What medication can be given to CRPS patients to prevent osteoporosis?
Vitamin C