PNS Pathology Flashcards
What is dysesthesiae?
-that tingly feeling when your arm falls asleep -symptom of sensory neuropathy
What is a mononeuropathy?
-neuropathy involving a single nerve
What is a mononeuropathy multiplex?
-a collection of mononeuropathies
What is a polyneuropathy?
-neuropathy in symmetric bilateral nerves -symptoms begin distally
Whats the difference between a neuropathy and a radiculopathy?
-Radiculopathy has dermatomal distribution, radiculopathy is peripheral nerve territory
What does electromyography test?
-spontaneous and evoked electrical activity in skeletal muscle
What does nerve conduction velocity test?
-velocity AND amplitude of compound action potentials
What is are the nerve conduction velocity test findings in demylenating neuropathies vs. axonal neuropathies?
Demylenating: -Conduction velocity reduced -Amplitude Dispersed Axonal: -Conduction velocity normal -reduced amplitude
What are the usual causes of axonal neuropathy?
-Toxic/metabolic neuropathies -Hyperglycemia in Diabetes -EtOH -Arsenic
What are the usual causes of axonal neuropathy?
-Guillian Barre Syndrome (acquired) -Charcot marie tooth disease (genetic)
What are the differences between neuropathic and myopathic changes on a muscle biopsy?
Neuropathic: -individual (angular) atrophic fibers -fiber type grouping -group atrophy Myopathic: -fiber size variability -basophilia -central nuclei -splitting -macrophages -fibrosis
What is the normal distribution of red vs white muscle fibers in a muscle biopsy?
-mixed randomly =mosaic distribution
What are the two broad disease processes involved in mopathy?
-Degenerative (i.e. dystrophy) -Inflammatory (i.e. myositis)
What is the difference between Duchenne’s and Becker’s dystrophies?
Duchenne’s:
- severe
- early onset
- rapid progression
Becker’s:
- Milder
- Later onset
- slower progression
On what chromosome is the dystrophin gene carried?
-X chromosome
Whad does Gower’s manuver indicate?
Duchenne’s muscular dystrophy
What type of myopathy are polymyositis and inclusion body myositis?
Inflammatory
How is inclusion body myositis different from polymyositis?
Inclusion body myositis is painless and immunosuppression is not effective in its treatment
