PATH: Peripheral Nerves/Muscle Disorders Flashcards
Mechanisms of Peripheral Nerve Pathology (Demylenation vs. Axonopathy)
Demyelination: Conduction Velocity Impacted
Axonopathy: Amplitude Impacted
Clinical Pattern of Peripheral Nerve Pathology?
Causes?
Clinical Pattern of Peripheral Nerve Pathology?
Causes?
Clinical Pattern of Peripheral Nerve Pathology?
Causes?
Autonomic Neuropathy Characteristics?
Proximal vs. Distal Motor Weakness?
Characteristics of Thiamine (B1) Deficiency?
Characteristics of Pyridoxine (B6) Deficiency?
Characteristics of Cobalamin (B12) Deficiency?
Diabetic Neuropathy
- Modalities Impacted
- Axonopathic/Demyelinating
- Characteristics
Uremia
- Modalities Impacted
- Axonopathic/Demyelinating
- Characteristics
Toxic causes of Peripheral neuropathy?
Spinocerebellar (Friedreich’s) Ataxia (SCA)
- Modalities Impacted
- Axonopathic/Demyelinating
- Characteristics
- Complications
Charcot-Marie-Tooth (CMT)
- Modalities Impacted
- Genetic Causes of each subtype (CMT 1A, CMT1B, CMT 1X, CMT2)
- Axonopathic/Demyelinating
- Presentation
- Complications
Hereditary Causes of Neuropathy?
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)
Infectious Causes of Neuropathy? How to Distinguish?
- Modalities Impacted
- Axonopathic/Demyelinating
- Presentation
- Complications
Paraneoplastic Neuropathy
- Modalities Impacted
- Axonopathic/Demyelinating
- Cause
Guillain-Barré Disease (Most Common Motor Neuropathy)
- Axonopathic/Demyelinating
- Pathogenesis
- Prognosis
Differences between LMN and UMN Disease?
________________: Fatigable (worse with exercise) weakness
Myasthenic: Fatigable (worse with exercise) weakness
_______________: inherited progressive muscular weakening and destruction/wasting
Dystrophies: inherited progressive muscular weakening and destruction/wasting
_______________: Involuntary sustained contraction or impaired relaxation of muscles
Myotoias: Involuntary sustained contraction or impaired relaxation of muscles
_______________: Ion channel disorders of muscle cells
Channelopathies: Ion channel disorders of muscle cells
Motor neuron disease characterized by:
- Focal muscle weakness and wasting
- Fasciculations
- Brisk reflexes
Pure UPPER motor neuron disease characterized by muscle weakness and wasting?
Progressive Muscular Atrophy
Pure UPPER motor neuron disease characterized by tetraperesis (RARE)
Primary Lateral Sclerosis
Motor Neuron disease characterized by fasciculating tongue?
Progressive Bulbar/Pseudobulbar Palsy
Myasthenia Gravis
- Pathogenesis
- Etiology
- Complications
- Treatment
Lambert-Eaton Myasthenic-Myopathic Syndrome (LEMS)
- Pathogenesis
- Presentation
Idiopathic inflammatory disease causing proximal skeletal muscle weakness and a characteristic rash probably mediated by autoimmunity?
- Presentation
- Pathogenesis
- Diagnosis
Dermatomyositis vs. Polymyositis?
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
Endocrine casues of Muscle Disease?
Electrolyte (Calcium/Potassium) casues of Muscle Disease?
Drug Mediated Muscle Toxicities
- ____________: Type II fibre atrophy
- __________ –proximal weakness
- _________ -myalgia
- _______________–rhabdomyolysis/necrotizing autoimmune myopathy
- _____________: Malignant neuroleptic syndrome (rigidity and autonomic instability
- _____________: Malignant Hyperthermia
Duchenne Muscular Dystrophy
Becker Muscular Dystrophy (later, milder)
Facioscapulohumeral Dystrophy
Which type of muscle disease is poorly tolerant of general anesthesia?
Myotonias: Sustained involuntary contraction and Impaired relaxation
Myotonia Congenita
- Autosomal Dominant vs. Recessive
- Exacerbating factors
Mytonic Dystrophy
- Autosomal Dominat or Recessive?
- Presentation?
Differences between the two Inhertied Paralytic Channelopathies?