110 - Peripheral Neuropathy Flashcards
What are peripheral nerves
All nerves outside the membrane of the CNS
What is a demyelinating neuropathy
Damage to Schwann cells/myelin sheaths resulting in neuropathy
Effects of demyelinating neuropathy
Slows conduction of signal.
Prognosis for demyelinating neuropathy
Usually reparable
Examples of demyelinating neuropathies
Guillan Barre, Compression syndromes.
What indicates axonal degeneration?
Lowered compound muscle action potential as fewer neutrons conducting within a bundle
Prognosis for axonal degeneration
Not usually reparable. Axons regrow but rarely replace
Examples of axonal degeneration neuropathies
Chronic Peripheral Neuropathy
Chronic peripheral neuropathy likely if
Glove and stocking presentation.
Slow progression, distal, symmetrical presentation
Common in alcoholism/B12 deficiency
What causes Guillian Barre syndrome
Often occurs post viral infection. Otherwise trauma, surgery or vaccinations.
May be causes by immune system mistaking myelin for pathogen
Symptoms/signs of Guillian Barre syndrome
Numbness/paralysis. Begins distally.
Investigations for Guillian Barre
Lumbar puncture for increased [protein] in CSF.
Nerve conduction studies to look at myelination
Prognosis for Gullian Barre
> 80% - full recovery as myelin repairs.
~5% mortality
Treatment for Guillian Barre
IV immunoglobulins.
Signs of ulnar nerve compression
Neuopathy in medial 1 1/2 fingers.
Hypothenar wasting.
Weakness in abduction and opposition in little finger.
