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Neuro > Muscular Movement and Diseases > Flashcards

Muscular Movement and Diseases Flashcards

1
Q

What is amyotrophy?

A

Loss of muscle bulk

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2
Q

What is sclerosis (in the context of ALS)?

A

“hardening” of the corticospinal tract

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3
Q

What upper motor neurons are affected by ALS?

A

betz and large pyramidal cell loss

astrocytic gliosis

lateral sclerosis

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4
Q

What lower motor neurons are affected by ALS?

A

anterior horn cell loss

spheroid, bunina bodies, and ventral root atrophy

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5
Q

What is the effect of ALS on muscles?

A

active denervation and reinnervation, group atrophy, type grouping

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6
Q

What are the symptoms of ALS associated with somatic lower motor neurons?

A

weakness, atrophy, fasciculations, cramps

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7
Q

What are the symptoms of ALS associated with somatic upper motor neurons?

A

weakness, spasticity, clonus, hyperreflexia/pathologic reflexes

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8
Q

What are the symptoms of ALS associated with bulbar lower motor neurons?

A

dysarthria, dysphagia, sialorrhea, palatal droop, tongue weakness, atrophy, and fasciculations

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9
Q

What are the symptoms of ALS associated with bulbar upper motor neurons?

A

dysarthria, dysphagia, pseudobulbar affect, jaw clonus, hyperactive gag, snout, glabellar

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10
Q

What lab tests can support an ALS diagnosis?

A

electrophysiologic tests (EMG/NCV)

neuroimaging studies (MRI)

muscle/nerve biopsy

blood tests

urine tests

CSF examination

biomarkers (blood/CSF)

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11
Q

What is the most common cause of death associated with ALS?

A

progressive respiratory insufficiency and decline in forced vital capacity

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12
Q

What genetic mutations are associated with ALS?

A

SOD1 mutation, C9orf72 (oxidative injury)

TAR-DNA binding protein 43 and FUS/TLS (RNA processing)

reduced transporter proteins (excitotoxicity)

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13
Q

What is the function of SOD1?

A

Ubiquitously expressed cytosolic enzyme that catalyzes detoxification of superoxide radicals

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14
Q

What are the effects of glutamate excitotoxicity on neurons?

A

Repetitive neuronal firing and calcium influx

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15
Q

What is the relationship between ALS and neurofilament accumulation?

A

neurofilament accumulation is associated with aging and is a main pathologic feature of ALS and can disturb axonal transport and lead to motor neuron loss

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16
Q

What neuromuscular disorderis caused by mutations in UBQLN2?

A

X-linked ALS and ALS/dementia

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17
Q

What is the functiono fRiluzole?

A

It is a treatment for ALS that reduces glutamate release

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18
Q

What is the best type of treatment for ALS?

A

a multidisciplinary team approach

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19
Q

What type of neurons (UMN/LMN) are affected in primary lateral sclerosis? How does the disease progress?

A

Pure UMN

Slowly progressive

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20
Q

What type of neurons (UMN/LMN) are affected in progressive muscular atrophy? How does the disease progress?

A

Pure LMN

Slowly progressive

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21
Q

What type of neurons (UMN/LMN) are affected in progressive bulbar palsy? Who does the disease normally affect?

A

UMN > LMN (restricted to bulbar area)

usually women > 65

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22
Q

What is the pathophysiology of excitotoxicity in ALS?

A

Astrocytes fail to remove excess glutamate from the synaptic space, resulting in excessive firing of motor neurons, increased calcium influx, and ER/mitochondrial stress

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23
Q

What are the main mechanisms that contribute to ALS?

A
  • glutamate excitotoxicity
  • neuro-inflammation
  • altered protein degradation
  • altered axonal transport
  • RNA metabolism errors
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24
Q

What symptoms of ALS can be treated?

A

cramps (with gabapentin, baclofen, etc), pain, spasticity (with baclofen, benzodiazepines, etc), sialorrhea (excess saliva), pseudobulbar affect (laughing and crying), respiratory problems, nutritional problems

Also can use mobility aids and adaptive devices

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25
Q

What is the function of edaravone?

A

A neuroprotective drug for ALS that acts as a free radical scavenger that can reduce oxidative stress

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26
Q

What is the difference in function between the medial and lateral motor systems?

A

Medial system - control of body axis and trunk as part of postural control and locomotion

Lateral system - control of limbs during learned or complex movements

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27
Q

What is the difference in localization between the medial and lateral motor systems?

A

Medial - bilateral

Lateral - contralateral

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28
Q

What is the path of corticospinal (pyramidal) tract neurons?

A

Descends from the primary motor cortex (and premotor/somatic sensory areas) through the posterior limb of internal capsule, crus cerebri, pons, and pyramids of brainstem –> decussates at the medullospinal junction –> descends through the spinal white matter of the lateral funiculus

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29
Q

What are the typical effects of a corticospinal injury in the upper motor neuron?

A

Contralateral hemiparesis and spasticity contralateral to the lesion

lesion is at the posterior limb of the internal capsule usually

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30
Q

Where does the rubrospinal tract run?

A

It descends from the magnocellular red nucleus in the midbrain to the spinal cord

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31
Q

What are the functions of the reticulospinal tract?

A

control of the body axis and trunk during reflex and locomotor activity, also major source of serotonin modulation

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32
Q

Where does the vestibulospinal tract originate?

A

Vestibular nuclei of pons and rostral medulla

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33
Q

What region of the reticulospinal tract acts as a neuromodular for serotonin?

A

reticulospinal axons from the raphe nuclei

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34
Q

What are the main destinations of the medial vestibulospinal tract/descending MLF?

A

lower motor neurons that innervate the neck muscles and stabilize the head

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35
Q

Where does the lateral vestibulospinal tract project?

A

projects ipsilaterally to excite antigravity leg muscles in a three neuron reflex pathway

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36
Q

What is the function of the lateral vestibulospinal tract?

A

Posture and balance

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37
Q

What is the effect of damage ot the lateral vestibulospinal tract?

A

postural instability with a tendency to fall towards the side of vestibular loss

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38
Q

What is the general organization of the motor map?

A

Lateral parts of the motor cortex = facial muscles

moving medially: fingers –> hands –> arms –> trunk–> legs

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39
Q

What is Brodmann’s area 4?

A

The primary motor cortex of the frontal lobe

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40
Q

What is the general physiology of the primary motor cortex neurons?

A

They are more related to triggering muscle force than any specific muscle movement

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41
Q

What is the response of the primary motor cortex to injury?

A

Small injuries can lead to reorganization and different areas can take on functions of the damaged regions

this is why the “phantom limb” phenomenon can happen

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42
Q

What is the structure and function of the premotor cortex?

A

Structure: area rostral to Brodmann’s area 4, sends dense axonal projections to the primary motor cortex

Function: active in advance of movements, especially active for visually guided movements

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43
Q

What is the structure and function of the supplementary motor area?

A

Structure: medially located

Function: responsive to internally guided sequences of movements (rather than in association with sensory guided movements)

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44
Q

What is the motor effect of damage to the cerebellar flocculus?

A

Gaze evoked nystagmus

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45
Q

What is the effect of vestibulocerebellar loss?

A

postural disorders, trunk ataxia, abnormal vestibulo-ocular reflex eye movements

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46
Q

What is the effect of loss of the vermis?

A

trunk ataxia, gait ataxia, lack of coordination of movement

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47
Q

What is the effect of intermediate cerebellar loss?

A

limb ataxia, overall lack of coordination of movement, reduced hand movements and fine coordination

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48
Q

What is the effect of lateral cerebellum loss?

A

impaired fine motor coordination, skilled hand movements, motor planning, and motor cognition

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49
Q

What is ataxia?

A

drunken or wobbly aspect to movement

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50
Q

What is dysmetria?

A

mis-reaching (usually hypermetria), over-reaching, or past pointing

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51
Q

What is decomposition of movements?

A

separation of multi-joint movements into single joint motions

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52
Q

What is intention tremor?

A

increased trembling of the extremity as a target object is approached

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53
Q

What is adiadochokinesia?

A

inability to make rapidly alternating movements (ex. quick transition between supination and pronation of hands)

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54
Q

What are some distinct signs of cerebellar injury?

A

ataxia, dysmetria, decomposition of movement, intention tremor, adiadochokinesia, inability to adjust movements or learn new movement patterns

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55
Q

What is the direct circuit sequence in the cerebellum?

A

mossy fibers synapse with granule cell dendrite at synaptic glomerulus –> granule cell with an axon that ascends toward the cerebellar surface to become a parallel fiber, which synapses onto purkinje cells –> purkinje cells project out of cerebellar cortex to deep nucleus neuron

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56
Q

What is the “error” signal of cerebellar circuitry?

A

A powerful climbing fiber projection from neurons of the inferior olive –> sends one fiber branch to each Purkinje cell and causes a massive calcium-based prolonged action potential that triggers long term depression

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57
Q

What are the major outputs from the cerebellum?

A

From deep nuclei directly and indirectly to the ventral lateral thalamus –> projects to motor and premotor cortex

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58
Q

What are the basal ganglia?

A

basal nuclei of the cerebrum that lie under the cerebral cortex that receive input from all of the cerebral cortex

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59
Q

What is the cerebral cortex input to the nuclei?

A

striatum/corticostriate pathway

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60
Q

What are the paths of projections through the basal ganglia?

A

inputs from cerebral cortex to basal ganglia –> outputs via dopamine receptor containing inhibitor GABA neurons to the internal segment of the globus pallidus and substantia nigra pars reticulata (output nuclei of basal ganglia that go to the ventral anterior and lateral thalamus)

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61
Q

What is the effect of excitation of D1 striatal neurons by the motor cortex?

A

Inhibits basal ganglia output (via direct pathway), leading to disinhibition of the thalamus –> promotes movement

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62
Q

The clinically most important motor pathway is the:

a) anterolateral system
b) corticospinal tract
c) dorsal column/medial lemniscus pathway
d) substantia nigra compact part
e) locus coeruleus

A

b) corticospinal tract

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63
Q

The major output pathway from the cerebellum is relayed via the:

a) basal ganglia
b) corticospinal tract
c) ventral thalamus
d) substantia nigra compact part
e) inferior olive

A

c) ventral thalamus

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64
Q

The major output pathway from the basal ganglia is relayed via the:

a) cerebellum
b) corticospinal tract
c) ventral thalamus
d) substantia nigra compact part
e) inferior olive

A

c) ventral thalamus

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65
Q

The output nucleus or nuclei of the basal ganglia is/are the:

a) substantia nigra pars reticulata and internal segment of the globus pallidus
b) fastigial, globose, emboliform, dentate, and vestibular nuclei
c) ventral thalamus
d) substantia nigra compact part
e) inferior olive

A

a) substantia nigra pars reticulata and internal segment of the globus pallidus

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66
Q

Responses of primary motor cortex neurons differ from those in the premotor areas by being more related to:

a) muscle force rather than movements of objects
b) sequences of internally generated movements rather than muscle force
c) visually guided movements rather than internally generated sequences of movements
d) extrinsic coordinates rather than intrinsic coordinates
e) ipsilateral body parts rather than contralateral body parts

A

a) muscle force rather than movements of objects

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67
Q

The output neuron of the cerebellar cortex is the:

a) granule cell
b) purkinje cell
c) basket cell
d) stellate cell
e) golgi cell

A

b) purkinje cell

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68
Q

After a large hemisphere stroke, the medial motor pathways may still be able to coordinate:

a) contralateral finger movements for grasping
b) dart throwing
c) the pinch grip
d) visually guided hand movements
e) locomotion

A

e) locomotion

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69
Q

A major contrast in signs between cerebellar patients and Parkinson’s disease basal ganglia patients, respectively, is:

a) dysmetria verses hypermetria
b) adiadochokinesia versus hypermetria
c) decomposition of movement versus akinesia
d) bradykinesia versus akinesia
e) akinesia versus ataxia

A

c) decomposition of movement versus akinesia

70
Q

A patient approaches you with his right arm flexed and right leg extended. Your examination reveals some sensory loss; eye movements are normal. What has most likely happened to cause this posture and gait?

a) LMN stroke of the ventral horn gray matter of spinal cord
b) LMN stroke of ventral horn white matter of spinal cord
c) UMN stroke of white matter of internal capsule
d) UMN stroke of gray matter of precentral motor cortex

A

c) UMN stroke of white matter of internal capsule

71
Q

What is the effect of injury to the dentate nucleus of the cerebellum?

A

impairs fine movements of hands and feet, motor planning

72
Q

What is the effect of injury to the vestibular nuclei?

A

loss of pursuit eye movements, dysmetria of VOR, vertigo and dysequilibrium

73
Q

What types of information is carried by the dorsal and ventral spinocerebellar tracts?

A

proprioceptive and tactile information from the lower limb and trunk

74
Q

Where is information carried from in the cuneocerebellar and rostral spinocerebellar tracts?

A

from the upper limbs and trunk

75
Q

How many times do each of the spinocerebellar tracts cross?

A

uncrossed - dorsal spinocerebellar, cuneocerebellar, and rostral spinocerebellar

twice crossed - ventral spinocerebellar

76
Q

What is the general path of neuronal circuitry in the cerebellum?

A

Mossy fibers from inputs signal to granule cells (excitatory) –> excites purkinje cells –> inhibits deep nuclear cell, leading to fine tuning of movements via the thalamus

Climbing fibers also interact with purkinje cells and can activate them orcause long term depression of firing

77
Q

What is long term depression of the cerebellum?

A

Occurs when climbing fibers provide an error signal when a movement has unwanted or unexpected results –> leads to decreased strength of synapses that caused the “wrong” movements

78
Q

A patient has dysdiadochokinesia and intention tremor of the right hand. Decomposition of movements is unclear, may be absent. The left hand is normal. There is no obvious postural sway in the Romberg test, no pronator drift, and gait appears normal. Where is the cerebellar lesion?

a) left vermis
b) left intermediate cerebellum
c) left lateral cerebellum
d) right vermis
e) right intermediate cerebellum
f) right lateral cerebellum

A

f) right lateral cerebellum

79
Q

What is the molecular process of muscle contraction?

A

membrane depolarizes –> SR opens and releases calcium –> calcium binds troponin –> tropomyosin moves and exposes myosin to actin –> crosbridge and power stroke

80
Q

What is the effect of neurogenic changes to muscle fibers on fiber arrangement?

A

Normal muscle = checker board pattern of different fiber types (determined by which nerve innervates the fiber)

If damaged nerve regenerates, the checker pattern is maintained

If the nerve that regenerates is a different nerve, it will innervate a group of surrounding muscle fibers that are all one type (type grouping) –> looks more patchy than checkered

81
Q

What are the pathological changes of muscle fibers associated with myopathic changes?

A

fiber type is maintained, but fibers become rounded in appearance

sometimes the fiber size varies, increased internalized nuclei, fatty infiltration, increased connective tissue, and inflammatory infiltrates

82
Q

What is the usual distribution of weakness associated with myopathy?

A

weakness (without any other symptoms) that is usually symmetric and proximally predominant

can also be asymmetric and distal for specific types of myopathies

83
Q

What reflex changes are associated with myopathies? Sensory changes?

A

Reflexes - usually normal

Sensory - usually normal

84
Q

What are the clinical features of dermatomyositis?

A

proximal predominant weakness progressing over weeks with characteristic skin lesions (heliotrope rash on face, erythema on trunk and hands)

also includes other systemic features

85
Q

What systemic features are associated with dermatomyositis?

A

cardiac (conduction defects and arrhythmias), pulmonary (ILD), GI (dysphagia, aspiration, delayed gastric emptying), joints (arthralgias without arthritis), vasculopathy (skin/muscle/GI), malignancy (increased risk), ocular (retinopathy, conjunctivitis, iritis, uveitis)

86
Q

What is the pathogenesis of dermatomyositis?

A

humorally mediated microangiopathy

87
Q

What are the biopsy findings of inflammatory myopathies?

A

perifascicular atrophy along with inflammatory cell infiltrates (mainly B cells) in the perivascular and perymysial regions

88
Q

What disease is associated with pathological findings of perifascicular atrophy with inflammatory infiltrates?

A

Dermatomyositis

89
Q

What is the treatment for dermatomyositis?

A

immunomodulating therapies (prednisone, methotrexate, etc)

90
Q

What are the clinical features of polymyositis?

A

similar to dermatomyositis but without skin involvement (proximal predominant weakness, multisystem involvement)

91
Q

What is the pathogenesis of polymyositis?

A

antigen-specific immune response directed against muscle fibers

92
Q

What are the muscle biopsy findings associated with polymyositis?

A

endomysial mononuclear inflammatory cells (mainly CD8+ T cells) surrounding and invading non-necrotic muscle fibers

93
Q

What is the clinical presentation of inclusion body myositis?

A

weakness involving wrist flexor and knee extensor muscles, predominantly in older adults

94
Q

What is the treatment of inclusion body myositis?

A

supportive care (not responsive to immunotherapy)

95
Q

What is the pathophysiology of Duchenne muscular dystrophy?

A

X-linked recessive mutation of the dystrophin gene that results in near or total loss of dystrophin protein

96
Q

What is the function of dystrophin protein?

A

Dystrophin is a sub-sarcolemma protein that serves as a structural link between the intracellular cytoskeleton and extracellular matrix

It stabilizes muscle membrane during contraction and relaxation

97
Q

What is the effect of loss of dystrophin?

A

muscle membrane disruption from structural failure, rupture and necrosis of muscle fibers, muscle gets replaced by fat and connective tissue

98
Q

What are the clinical features of Duchenne muscular dystrophy?

A
  • usually normal at birth, proximal weakness in legs > arms by age 2-6, and wheelchair by age 12
  • calf hypertrophy
  • respiratory function decline
  • cardiac involvement
  • early rise in CK
99
Q

What are the muscle biopsy findings associated with Duchenne muscular dystrophy?

A

increased connective tissue, fiber size variability, scattered necrotic and regenerating fibers, immunohistochemistry demonstrates reduced or absent dystrophin on the sarcolemma

100
Q

What are the treatments for Duchenne muscular dystrophy?

A

corticosteroids

101
Q

What is Becker muscular dystrophy? What are the clinical features?

A

X-linked recessive mutation of dystrophin gene where dystrophin is semifunctional and of abnormal size and/or amount

Clinical features: similar to DMD, but slower progression and later onset

102
Q

What are the muscle biopsy findings associated with Becker muscular dystrophy?

A

similar to DMD, but less severe

IHC demonstrates present but reduced dystrophin on the sarcolemma

103
Q

What is limb-girdle muscular dystrophy?

A

a heterogenous group of muscle disorders that can be dominant or recessive that are similar to the dystrophinopathies

104
Q

What is the pathophysiology of Pompe disease/Acid Maltase deficiency?

A

autosomal recessive disorder caused by mutation of lysosomal acid alpha-glucosidase

glycogen is normally degraded in lysosomes by acid maltase to glucose; failure of enzyme results in glycogen accumulation which can displace organelles or lysosomal rupture

105
Q

What are the clinical features of acid maltase deficiency?

A

infantile: generalized weakness and hypotonia
adult: respiratory and limb-girdle weakness

106
Q

What is the pathophysiology of myophosphorylase deficiency?

A

autosomal recessive disorder caused by mutation of gene that encodes myophosphorylase –> leads to impaired glycolysis during anaerobic activity and glycogen accumulation

also leads to increased ADP and decreased inorganic phosphate, which can disrupt muscle cross-linking

107
Q

What are the clinical features of myophosphorylase deficiency?

A

exercise intolerance in childhood, exertional pain with brief intense (anaerobic) activities, myoglobinuria

108
Q

What are the muscle biopsy findings associated with myophosphorylase deficiency?

A

subsarcolemmal glycogen collections can be seen with PAS staining; phosphorylase stain shows no activity

109
Q

Why do defects in the transport of long-chain fatty acids and metabolism of lipids lead to myopathies?

A

long-chain fatty acids are a major source of fuel both at rest and following prolonged activity

110
Q

What are the clinical manifestations of lipid storage disorders?

A

progressive muscle weakness and hypotonia or recurrent rhabdomyolysis after exercise

111
Q

What is the pathogenesis of steroid myopathy?

A

corticosteroids bind receptors on target cells, which may result in decreased protein synthesis, increased protein degradation, impaired mitochondrial function, or decreased sarcolemmal excitability

112
Q

What are the clinical features of steroid myopathy?

A

proximally predominant weakness may develop acutely in the setting of high dose IV corticosteroids, over weeks after starting high dose oral steroids, or slowly with progressive deterioration during chronic corticosteroid ingestion

113
Q

What are the muscle biopsy findings associated with steroid myopathy?

A

type 2 fiber atrophy

114
Q

What is the pathogenesis of statin myopathy?

A

HMG-CoA reductase inhibitors block production of cholesterol and geranylgeraniol –> important in production of CoQ10 (ATP production), dolichol (glycoprotein synthesis), isopentyladine (tRNA), and activation of regulatory proteins

115
Q

What are the clinical features of statin myopathy?

A

ranges from asymptomatic hyper CK-emia to myalgias and mild weakness to severe proximal weakness

116
Q

What are the muscle biopsy findings associated with statin myopathy?

A

scattered muscle fiber necrosis with phagocytosis and small regenerating muscle fibers

117
Q

What are examples of presynaptic disorders of the NMJ?

A

lambert eaton myasthenic syndrome, botulism/botulinum toxin, choline acetyltransferase deficiency

118
Q

What are synaptic disorders of the NMJ?

A

acetylcholinesterase deficiency, organophosphate toxicity

119
Q

What are postsynaptic disorders of the NMJ?

A

myasthenia gravis, drug induced, toxic

120
Q

What are the clinical features of myasthenia gravis?

A

fluctuating weakness of any voluntary muscle group, typically worsened by activity or stressors

121
Q

What are the ocular and bulbar symptoms of myasthenia gravis?

A

ocular: diplopia, ptosis

bulbar dysfunction: speech changes, chewing and swallowing difficulties

122
Q

What are the physical exam findings of myasthenia gravis?

A

diffuse weakness

eye movement abnormalities

eyelid and mouth closure weakness

speech slurred with nasal quality

respiratory decline

123
Q

What is the edrophonium (tensilon) test?

A

Administration of a short acting acetylcholinesterase inhibitor that can test for myasthenia gravis (but is not used anymore)

124
Q

What is the treatment for myasthenia gravis?

A

acetylcholinesterase inhibitors, corticosteroids, immunomodulation, thymectomy (if thymoma or thymic hyperplasia)

125
Q

Damage to what structures results in demyelination?

A

Schwann cells or myelin sheath

126
Q

What is Wallerian degeneration?

A

degeneration of the distal portion of a nerve that occurs after injury in a discrete localized event

127
Q

What can occur to a nerve after injury?

A

It can re-grow either from the injured nerve or a neighboring nerve that sprouts to ennervate the denervated muscle

128
Q

What is the role of Schwann cells in nerve regeneration?

A

they proliferate and form bands of bungner, which provide a substrate for axonal regeneration

129
Q

What are the general patterns of symptoms in peripheral axonal neuropathies?

A

symmetric and affect longest nerves first

sensory symptoms predominate, but motor symptoms can occur too

130
Q

What are the general patterns of symptoms for demyelinating neuropathies?

A

proximal and distal symptoms

131
Q

What are the sensory symptoms of peripheral neuropathies?

A

sensory loss, paresthesias

large sensory fiber involvement = deficits in vibration and proprioception

small fiber involvement = pain and temperature perception

132
Q

What diagnostic tools are useful for evaluating peripheral neuropathy?

A

serum studies

CSF examination

nerve conduction studies

nerve biopsy

133
Q

What is the pathophysiology of acute inflammatory demyelinating polyneuropathy?

A

molecular similarity between myelin proteins and glycolipids expressed by several infectious agents, so antibodies against these agents may cross react with specific antigens on the Schwann cells and myelin –> results in cascade activation, lysis of myelin sheaths, inflammation

134
Q

What are the clinical features of acute inflammatory demyelinating polyneuropathy?

A

progressive, fairly symmetric proximal and distal weakness with absent or depressed deep tendon reflexes

autonomic and respiratory involvement common

symptoms peak by week 4

135
Q

What are the lab/study findings associated with acute inflammatory demyelinating polyneuropathy?

A

lab: elevated CSF protein with normal WBC count

nerve conduction studies: slowed conduction velocities (segmental demyelination)

136
Q

What are the treatments for acute inflammatory demyelinating polyneuropathy?

A

plasma exchange or IVIg

supportive care

not corticosteroids

137
Q

What is chronic inflammatory demyelinating polyneuropathy? What is the treatment?

A

chronic immune-mediated polyneuropathy, progresses for greater than eight weeks

treatment: IVIg or corticosteroids or other immunomodulating medications, supportive care

138
Q

What is charcot-marie-tooth disease type 1?

A

a spectrum of disorders caused by a specific mutation in one of seberal myelin genes that results in defects of myelin structure, maintenance, and formation

139
Q

What are the clinical features of carcot-marie-tooth disease type 1?

A

distal calf muscle atrophy –> stork leg deformity

clumsy walking (weakness and sensory loss that is gradual and mainly involves proprioception and vibration)

140
Q

What endocrinopathies are associated with neuropathy?

A

diabetes mellitus, hypothyroidism

141
Q

What systemic diseases are associated with neuropathy?

A

connective tissue disease, IBD, liver disease, uremia

142
Q

What nutritional deficiencies are associated with neuropathy?

A

vitamin (B12, B6, vitamin E)

copper, phosphate

alcohol

143
Q

What infections are associated with neuropathies?

A

viral: HIV, HTLV-1, hep B and C
bacterial: lyme, leprosy

144
Q

What is the most common presentation of diabetic polyneuropathy?

A

distal symmetric sensory polyneuropathy

length dependent affecting both small and large fibers

145
Q

What is the treatment for diabetic polyneuropathy?

A

tight blood sugar control and symptom management

146
Q

What is the presentation of neuropathy associated with vitamin B12 deficiency?

A

CNS and/or PNS abnormalities, dysfunction of posterior columns and/or corticospinal tracts

leads to reduced vibratory and proprioception with spastic paraparesis

147
Q

Which type of neuropathy requires pain management?

A

small fiber (large fiber leads to numbness, not pain)

148
Q

What fibers are affected by large fiber neuropathy?

A

myelinated A-beta fibers (proprioception, fine touch, vibration)

myelinated A-alpha fibers (motor strength)

149
Q

What is Guillain-Barre Syndrome?

A

an acute demyelinating polyneuropathy with ascending paresis and sensory changes

150
Q

What gene is associated with MS?

A

polymorphisms of the major histocompatibility complex

151
Q

What is the pathology of multiple sclerosis?

A

involves gray and white matter regions

areas of demyelination and axonal loss, associated with inflammatory lymphocytes and activated macrophages

152
Q

What type of lymphocytes predominate in MS plaques? Perivascular distribution?

A

Plaques: CD8+ T lymphocytes, plasma cells, B lymphocytes

Perivascular distribution: CD4+ T lymphocytes

153
Q

What is the pathophysiology of MS?

A

demyelinated axons = slowed/blocked signal transmission that disrupts conduction of nerves

sodium channels are elaborated to maintain conduction, but there is an increased metabolic demand and it is slower

154
Q

What are the clinical features of MS?

A

symptoms organized around relapses and exacerbations

common symptoms: sensory changes, vision loss, weakness, spasticity, cerebellar dysfunction, neurologic symptoms, cognitive impairment, etc

155
Q

What is L’Hermitte’s sign?

A

brief electrical shock-like sensation momentarily down the spine triggered by neck flexion

156
Q

What is Uthoff’s phenomenon?

A

recurrent visual blurring in a patient with previous optic neuritis

157
Q

What are pseudo-relapses of MS?

A

recurrent symptoms provoked by fever or intercurrent ilness that may mimic exacerbations, but do not require anti-inflammatory treatment

158
Q

What is relapsing-remitting MS?

A

A form of MS that presents with an attack of symptoms followed by complete or partial symptomatic recovery

159
Q

What is primary vs. secondary progressive MS?

A

primary MS = disease that progresses from the onset

secondary MS = progressive worsening later in course of disease

160
Q

What are “Dawson’s fingers”?

A

lesions seen on MRI that are ovoid and perpendicular to the ventricles

161
Q

What is the most useful imaging technique for MS?

A

MRI

162
Q

What is neuromyelitis optica spectrum disorder?

A

A disease similar in presentation to MS with longitudinally extensive spinal cord lesions and is often positive for NMO/AQP4 - IgG antibody

163
Q

What is acute disseminated encephalomyelitis?

A

A post-infectious or post-vaccination demyelinating event associated with headache, seizures, and mental status change. MRI shows extensive brain lesions and longitudinally extensive spinal cord lesions

164
Q

What are the treatments for multiple sclerosis (generally)?

A

disease modifying therapies

managing symptoms

wellness and co-morbidities (weight loss, stopping smoking, dietary changes)

165
Q

Which of the following factors is not associated with an increased risk of developing multiple sclerosis?

a) low vitamin D levels
b) alcohol use
c) tobacco smoking
d) residence in temperature latitudes

A

b) alcohol use

166
Q

Which of the mechanisms is not considered to be a pathologic feature of multiple sclerosis?

a) innate immune activation
b) axon damage due to metabolic stress
c) loss of Schwann cells
d) elaboration of increased sodium channels in demyelinated axons

A

c) loss of Schwann cells

167
Q

Diagnosis of MS using the McDonald 2017 criteria requires which of the following?

a) typical lesions in multiple characteristic locations in the CNS
b) typical lesions in characteristic locations occurring at different times
c) typical lesion in characteristic locations at one time point and unique CSF oligoclonal bands
d) any of the above
e) a and b

A

d) any of the above

168
Q

Typical acute CNS demyelinating symptoms include all of the following except?

a) optic neuritis
b) partial myelitis
c) abrupt onset of hemiparesis
d) double vision
e) balance impairment

A

c) abrupt onset of hemiparesis

169
Q

Neuromyelitis optic spectrum disorder is not associated with which of the following?

a) blood test positive for anti-MOG antibody
b) blood test positive for aquaporin 4 antibody
c) gradually progressive neurologic disability
d) presentation with acute attacks resulting from lesions in the brainstem

A

c) gradually progressive neurologic disability

170
Q
A

Neuro (12 decks)

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