PATH: Peripheral Nerves/Muscle Disorders

Question 1

Mechanisms of Peripheral Nerve Pathology (Demylenation vs. Axonopathy)

Answer 1

Demyelination: Conduction Velocity Impacted

Axonopathy: Amplitude Impacted

Question 2

Clinical Pattern of Peripheral Nerve Pathology?

Causes?

Answer 2

Question 3

Clinical Pattern of Peripheral Nerve Pathology?

Causes?

Answer 3

Question 4

Clinical Pattern of Peripheral Nerve Pathology?

Causes?

Answer 4

Question 5

Autonomic Neuropathy Characteristics?

Answer 5

Question 6

Proximal vs. Distal Motor Weakness?

Answer 6

Question 7

Characteristics of Thiamine (B1) Deficiency?

Answer 7

Question 8

Characteristics of Pyridoxine (B6) Deficiency?

Answer 8

Question 9

Characteristics of Cobalamin (B12) Deficiency?

Answer 9

Question 10

Diabetic Neuropathy

• Modalities Impacted
• Axonopathic/Demyelinating
• Characteristics

Answer 10

Question 11

Uremia

• Modalities Impacted
• Axonopathic/Demyelinating
• Characteristics

Answer 11

Question 12

Toxic causes of Peripheral neuropathy?

Answer 12

Question 13

Spinocerebellar (Friedreich’s) Ataxia (SCA)

• Modalities Impacted
• Axonopathic/Demyelinating
• Characteristics
• Complications

Answer 13

Question 14

Charcot-Marie-Tooth (CMT)

• Modalities Impacted
• Genetic Causes of each subtype (CMT 1A, CMT1B, CMT 1X, CMT2)
• Axonopathic/Demyelinating
• Presentation
• Complications

Answer 14

Question 15

Hereditary Causes of Neuropathy?

Answer 15

Spinocerebellar (Friedreich’s) Ataxia (SCA)

• Sensory/Axonopathic
• Inactivating GAA repeats in Frataxin gene
• Impaired mitochondrial iron handling
• Difficulty walking (before 20)
• Pes Cavus & Kyphoscoliosis
• Cardiomyopathy
• Optic atrophy

Charcot-Marie-Tooth (CMT)

• Sensory and Motor / Demylenating (CMT2 Axonopathic)
• Autosomal Dominant or X-Linked (CMT 1X)
• Foot drop & wasting
• Champagne bottle/Stork legs
• Pes Cavus & Scoliosis
• Schwann cell hyperplasia and hypertrophic neuropathy (except CMT 2)

Question 16

Infectious Causes of Neuropathy? How to Distinguish?

• Modalities Impacted
• Axonopathic/Demyelinating
• Presentation
• Complications

Answer 16

Question 17

Paraneoplastic Neuropathy

• Modalities Impacted
• Axonopathic/Demyelinating
• Cause

Answer 17

Question 18

Guillain-Barré Disease (Most Common Motor Neuropathy)

• Axonopathic/Demyelinating
• Pathogenesis
• Prognosis

Answer 18

Question 19

Differences between LMN and UMN Disease?

Answer 19

Question 20

________________: Fatigable (worse with exercise) weakness

Answer 20

Myasthenic: Fatigable (worse with exercise) weakness

Question 21

_______________: inherited progressive muscular weakening and destruction/wasting

Answer 21

Dystrophies: inherited progressive muscular weakening and destruction/wasting

Question 22

_______________: Involuntary sustained contraction or impaired relaxation of muscles

Answer 22

Myotoias: Involuntary sustained contraction or impaired relaxation of muscles

Question 23

_______________: Ion channel disorders of muscle cells

Answer 23

Channelopathies: Ion channel disorders of muscle cells

Question 24

Motor neuron disease characterized by:

• Focal muscle weakness and wasting
• Fasciculations
• Brisk reflexes

Answer 24

Question 25

Pure UPPER motor neuron disease characterized by muscle weakness and wasting?

Answer 25

**Progressive Muscular Atrophy**

Question 26

Pure UPPER motor neuron disease characterized by tetraperesis (RARE)

Answer 26

**Primary Lateral Sclerosis**

Question 27

Motor Neuron disease characterized by fasciculating tongue?

Answer 27

**Progressive Bulbar/Pseudobulbar Palsy**

Question 28

**Myasthenia Gravis** - Pathogenesis - Etiology - Complications - Treatment

Answer 28

Question 29

**Lambert-Eaton Myasthenic-Myopathic Syndrome (LEMS)** - Pathogenesis - Presentation

Answer 29

Question 30

Idiopathic inflammatory disease causing proximal skeletal muscle weakness and a characteristic rash probably mediated by autoimmunity? - Presentation - Pathogenesis - Diagnosis

Answer 30

Question 31

Dermatomyositis vs. Polymyositis?

Answer 31

**Polymyositis** - Like dermatomyositis but No Rash - Endomysial CD8+ cytotoxic T-cells directly injuring Myocytes **Dermatomyositis** - CD4+ T-cell and B-cells => perimysial vessels => Perifascicular Atrophy

Question 32

Endocrine casues of Muscle Disease?

Answer 32

Question 33

Electrolyte (Calcium/Potassium) casues of Muscle Disease?

Answer 33

Question 34

**Drug Mediated Muscle Toxicities** * ____________: Type II fibre atrophy * __________ –proximal weakness * _________ -myalgia * _______________–rhabdomyolysis/necrotizing autoimmune myopathy * _____________: Malignant neuroleptic syndrome (rigidity and autonomic instability - _____________: Malignant Hyperthermia

Answer 34

Question 35

Answer 35

**Duchenne Muscular Dystrophy** **Becker Muscular Dystrophy** (later, milder)

Question 36

Answer 36

**Facioscapulohumeral Dystrophy**

Question 37

Which type of muscle disease is poorly tolerant of general anesthesia?

Answer 37

**Myotonias**: Sustained involuntary contraction and Impaired relaxation

Question 38

**Myotonia Congenita** - Autosomal Dominant vs. Recessive - Exacerbating factors

Answer 38

Question 39

**Mytonic Dystrophy** - Autosomal Dominat or Recessive? - Presentation?

Answer 39

Question 40

Differences between the two Inhertied Paralytic Channelopathies?

Answer 40