Lecture 20 and 21 -- Peripheral Neuro D/o

Question 1

UMN symptoms

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LMN symptoms
what is the specific and classic LMN symptom?
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Answer 1

Upper Motor Neuron:

Weakness
Spasticity (Stiff)
Increased DTRs, Clonus
Pathological Reflexes
(up going babinksi) 

Lower Motor Neuron
Weakness,
Muscle atrophy,
Fasciculation’s

Question 2

sensory neuropathy’s — large fiber vs small fiber symptoms –

where do the tracts run?

Answer 2

large Fibers; Dorsal Column
Light touch
Vibration
Joint position sense

	Small Fibers/Lateral Spinothalamic tracts 
		Pinprick Temperature

Question 3

Idiopathic Motor Neuron disorder?

2 Hereditary hereditary motor neuron disorders ?

2 infectious motor neuron d/o?

Answer 3

ALS

Hereditary – Spinal muscular trophy
Kennedy disease

Infections - Poliomyelitis, WNV

Question 4

ALS –
describe the symptomatology? what are some early symptoms? classic findings?

upper motor symptoms?
Lower motor symptoms?
sensory symptoms ?

Answer 4

UMN - Yes – Hyperreflexia, spasticity, weakness
LMN - yes – muscle atrophy, weakness, fasiculations
Sensory deficits – No
Cognitive/behavior – yes (disinhibition)

® Early -- Muscle cramps and fasiculations 
® Limb weakness -- asymmetric; moves to opposite side before progressing distally 
	◊ Muscle atrophy and spasm 
® Bulbar-- slurred speech and dysphagia of liquid/solids 
® Tongue Atrophy

Question 5

Spinal Muscle Atrophy -- classic finding in kids?
genetic inheritence pattern? 
UMN sx?
LMN sx?
Sensory sx ?

Answer 5

Floppy baby
 AR 
UMN - no 
LMN -yes 
Sensory - no

Question 6

• Kennedy disease – (aka Spinal-bulbar muscular atrophy)
Genetic Inheritence?
genetic mutation? – what other manifestations arise from this ?

pathognomonic combination of findings?
UMN sx?
LMN sx?
Sensory sx ?

Answer 6

LMN findings only
Key finding: Fasciculation’s of the tongue in a floppy baby

XLR – mutation of the Androgen receptor
therefore children with androgen insensitivity

Question 7

Infectious – what types of viruses?

UMN sx?
LMN sx?
Sensory sx ?

Answer 7

polio, WNV

polio = descending flaccid paralysis

Only LMN

Question 8

Causes of DRG (sensory) disease?

Answer 8

○ Paraneoplastic with anti-Hu antibody
		○ Sjogren’s syndrome
		○ Acute autoimmune sensory neuronopathy
		○ Toxic
			• Cis platinum

Question 9

radiculopathy – where is the damage?

Symptoms and findings?
what is the most common cause?
what is the most common location?

Answer 9

– lesion at the dorsal nerve root which is a union of a sensory dorsal root and motor ventral root

Symptoms: Pain, tingling, numbness, weakness
Findings – sensory nerve conduction testing is totally normal bc the DRG is intact

cause – Trauma, disk hernia, infection

Most common Cervical - C 7
Mostly Lumbosacral – L5, S1
Lumbsacral > Cervical

Question 10

Disorders of the plexus –

what are the plexi?
symptoms?
common causes?

Answer 10

(lumbosarcal plexus and branchial plexus)

Common cause: Trauma to the plexus and trauma during childbirth 
	Other -- neoplasma, trauma, hematoma, abscess, radiation, immune

Sensory and Motor Signs -- bc this is a Mixed Root;

Question 11

D/o of peripheral Nerves – (neuropathy)

what is the most common cause?
What is the classical distribution pattern?

how can it present? (symptoms)

Answer 11

DM
Glove and Stocking distribution

Sensory signs
Motor Signs
Autonomic Signs

Question 12

Examples of sensory signs in neuropathy? (differences between large myelinated vs small myelinated/unmyelinated?)

Example of motor signs?

Examples of autonomic signs?

Answer 12

Sensory – numbness, paresthesias, dyesthesia, allodynia, hyperpathia

Large Myelinated – Joint position and Vibration
Small Myelinated/Unmyelinated – temperature, hyperalgesia

Motor - weakness, fasciulations, temors

Autonomic – anhydrosis, orthrostatic, GU, GI, sexual,

Question 13

name some causes of peripheral neurpathy?

Answer 13

• Mononeuropathy – Carpal Tunnel
  * Systemic D/o – DM, B12 def, Infection (HIV, Hepatitis)
  * Genetic – Charot Marie Tooth

Demyelinated –GBS, CIPD

Question 14

carpal tunnel –

distribution of disturbance?
positive signs?
associated conditions?

Answer 14

Sensory disturbance to: First three digits and part of the fourth
Wekaness and atrophy of the thenar muscles
Positive Phalen’s and Tinel’s Test

Associated conditions — pregnancy, occupation, RA, DM, HTN

Question 15

Charcot Marie Tooth – Neuropathy
mutation to?
pathology?
reason for this pathology?

Answer 15

PMP22
Chronic and demyelinating condition
Leading to onion skinning

Question 16

Guillaine Barre Syndrome 
aka? 
mediated by what cell type? 
Preceding condition? 
type of paralysis

Answer 16

T cell mediated auto immune attack on myeline

aka – acute inflammatory demyelinating polyradiculoneuropathy (acute in presentation)

Ascending paralysis

Preceded by infection (campylobacter, CMV, EBV)

Question 17

CIPD
pathology?
reason for this pathology

Answer 17

A chronic form of GBS;

Immune mediated

chronic demyelinating

Question 18

what two disease present with onion skinning pathology?

Answer 18

Charcot Marie Tooth

CIPD

Question 19

what form of neuropathy does not follow the glove/stocking distribution?

describe the pathology

Answer 19

Vasiculitis Neuropathy –
random patterns of neuropathy

bx is taken looking for vasculitis, not necessarily the nerve

Question 20

Disorders of the presynpatic NMJ?

describe the pathology

Answer 20

Lambert Eaton – autoimmune attack of P/Q VG Calcium Channels -

Botulism – Clostridium Botulinum spores; prevents vesicles from binding to presynaptic membrane

Question 21

Lambert Eaton –

improves with what?
What should you always check for if this condition presents?

Answer 21

Improves with repetitive motions; flooding the cell with calcium to improve release of vesicles

Associated with Small Cell Lung Cancer (paraneoplastic syndrome)

Question 22

post synaptic d/o at the NMJ?
pathology?
how does it present?

Answer 22

Myasthenia Gravis –
autoimmune d/o at the ACHR-nicotinic

presents with flucutating strength and weakness
Unilateral ptosis, but can affect any muscle

Proximal disease > distal

Question 23

what bacteria is classically associated with demyelination?

what other bacteria and viruses are associated with axonal destruction and demyelination

Answer 23

Diphteria toxin

Leprosy (former most common cause of neuropathy)

Varicella Zoster

Question 24

What are the 5 forms of myopathy? — name specific of each

what serum value is typically elveated with muscle damage?

Answer 24

Creatinine (Phospho) Kinase – elevated

Congential – (Nemeline, central core disease)

Metabolic – (Mitochondrial disease, Glycogen storage)

Inflammatory (Polymyositis, Dermatomyositis, Inclusion body myositis)

Dystrophies – (Duchene’s, Becker’s, Myotonic)

Toxic –Statins, EtOH

Question 25

Congential Myopathes –
Nemeline,
what does histology look like?

central core disease
Pathophysiology;
associated with what deadly process?
pathology?

Answer 25

Nemaline Myopathy – rods = expansion of Z disk material;

Central core disease – absence of staining in the center
Ryanodine Receptor gene mutation
Patients are susceptible to Malignant Hyperthermia

Question 26

Metabolic –

Mitochondrial disease – classic histology?

Glycogen storage — name a disease; what is the classic histo

Answer 26

Mitochondrial Myopthathy –
Ragged Red Fibers
Parking space inclusions on EM

Glycogen Storage diseases — Pompe’s Disease
Accumulation of Glycogen

Question 27

Inflammatory

mediated by what cell type?
Classic histology of each of the following?

Polymyositis,

Inclusion body myositis

Answer 27

Cytotoxic T cells for Both (CD8)

Polymyositis – lymphocytes invading non necrotic fibers

Inclusion body myositis
light microscopy – rimmed vacuoles

Question 28

Dermatomyositis
mediated by what cells?
pathognomonic findings?
Histology?

what should you also screen for?

Answer 28

CD4 Mediated
Rashes: Heliotrope rash, V sign, Gottrons Sign
perifascicular atrophy

also screen for PNPs

Question 29

with what disease should you screen for PNPs?

Answer 29

Lambert Eaton

Dermatomyositis

Question 30

Dystrophies –

Duchene’s vs Becker’s,

how can you differentiate the two (what lab studies)?

pathology

classic distribution for dystrophic myopathies?

Answer 30

Duchene’s – complete loss of dystophin – more severe phenotype

Beckers – partial loss – more mild phenotype

Consistent with IHC and Western Blot Findings
pathology – endomysial fibrosis

Limb Girdle Syndromes