Peripheral neuropathy Flashcards
Describe the characteristics of the following types of nerve damage in terms of symptoms, power, sensation and reflexes:
- large motor fibre
- large sensory fibre
- Small fibre
- Autonomic
-weakness, unsteadiness, wasting
reduced
normal
absent
-numbness, parasthesia, unsteadiness
normal
vibration and JPS reduced
absent
-pain, Dysesthesia
normal
pin prick and temp reduced
present
-dizzines (postural hypotension), impotence, nausea and vomiting (gastroparesis)
normal
normal
present
Name the different points at which nerve damage can occur?
Order is from spinal cord proximity outwards:
radiculopathy
Plexopathy
peripheral neuropathy (mononeuropathy, mononeuritis multiplex, length dependent)
Describer the features of the types of peripheral neuropathy:
mononeuropathy
mononeuritis multiplex
length dependent
- effects a single nerve e.g. carpal tunnel
- multiple whole nerves taken out, asymmetrical, assoc with vasculitis
- symmetrical, effects the longest nerves from hands and feet up
Describe the possible patterns of loss that occur with:
- length dependant?
- Mononeuritis/ Mononeuropathy?
- what investigation should be done?
-glove and stocking, mild-severe
-might get muscle wasting in thenar eminence
on neuritis: wrist and foot drop
-nerve conduction study
What are the 2 ways in which nerves can be damaged?
-what would investigation show?
-Axonal loss
Peripheral nerve demyelination
-demyelinating= bizarre and jittery,
demyelinating neuropathy
-types? (2) and causes of each types? (1,2)
-Acute
GBS(Guillaine Barre syndrome or AIDP)
Chronic
CIDP (chronic inflammatory demyelinating polyradiculopathy)
Hereditary sensory motor neuropathy
Guillan-Barre syndrome
- what is it?
- presentation?
- cause?
- treatment?
-progressive paraplegia over days up to 4 weeks
sensory symptoms proceed weakness
- acute, ascending and progressive neuropathy, characterised by weakness, paraesthesiae and hyporeflexia
- might be post infection e.g. campylobacter
- immunoglobulin infusion or plasma exchanges
Hereditary neuropathy
- types? (6)
- inv?
- signs in type 1?
- motor, sensory, sensorimotor, small fibre, autonomic variants , congenital insensitivity to pain syndrome
- genetic testing for common mutations e.g. CMT1a
-foot deformity
champagne bottle wasting (of tibial muscle)
Causes of axonal neuropathies?
- vasculitic? (2)
- paraneoplastic? (2)
- infections? (4)
- drug/toxin? (4)
- Metabolic? (5)
Idiopathic!!
- ANCA +ve, RA, sjogrens
- Myeloma, antibody mediated
- HIV, syphilis, Lyme, hepatitis
- Alcohol, amioderone, phenytoin, chemo
- DM, B12/folate def, Hypothyroidism, chronic uremia, pophyria
Autonomic neuropathy:
-give the two types and their causes?
-Chronic
DM, Amyloidosis, hereditary
Acute
GBS, Porphyria
Treatment of peripheral neuropathy:
- Axonal? (3)
- demyelinating? (3)
-Treat cause (i.e. clear hepatitis)
Symptomatic treatment (physio, orthotics, neuropathic pain relief)
Vasculitic- IV methylprednisolone + cyclophosphamide
-IVIg
steroids
azathioprine, mycophenalate, cyclophosphamide