Neuropathies (Ferguson) Flashcards
1
Q
Anatomy of a peripheral nerve
A
2
Q
Diagnosis:
- The most common form of hereditary motor-sensory neuropathy
- Represents a rather heterogeneous group of genetically distinct disorders with similar clinical presentations [Type1, Type2, TypeX]
- Type 1 - CMT1; Demyelinating
- Type 2 - CMT2; Axonal
- Type X - CMTX; X-linked
A
Charcot Marie Tooth
3
Q
What type of CMT?
- AD inheritance, disorder of peripheral demyelination resulting from a mutation in the peripheral myelin protein - 22 (PMP22) gene
- Nerves can get quite large in segments where they have been demyelinated and remyelinated over and over
- Typically presents in teenage years or early adulthood, marked by distal muscle wasting and weakness - often affects legs first (high arches, hammer toes)
- Progressive weakness; can leave patients wheelchair bound later in life
- Usually do not complain of numbness - may be because patients have never had normal sensation
A
CMT Type 1 - Demyelinating
4
Q
What type of CMT?
- Autosomal dominant
- Disorder that results in axonal damage
- Slower progression than CMT1 - many patients continue to ambulate with the assistance of a cane or ankle-foot orthotics to prevent foot drop
A
CMT Type 2 - Axonal
5
Q
What type of CMT?
- X-linked inheritance, absence of male to male transmission within kin - carrier females are less severely affected
- ~15% of all CMT; onset typically in second decade
- MIxed axonal and demyelinating - symptoms begin as frequent falls; exercise intolerance and cramping
A
CMT Type X - both axonal and demyelinating
6
Q
CMT Diagnostic evaluation:
- Typically clinical and based on _______
- Neurophysiologic studies like _____, help differentiate whether the disease is demyelinating or axonal
- Also _______ can confirm, but expensive and not really utilized, like sural nerve biopsy.
Tx:
- No preventative or disease suppressing tx available
- Patients may require surgical intervention for tendon lengthening or to correct other problems eg scoliosis
A
- family history
- nerve conduction studies
- genetic testing
7
Q
Diagnosis?
- Neuronal injury due to lack of oxygen from decreased blood flow or inflammation of blood vessels causing destruction of the vessel wall and occlusion of the vessel lumen of small epineural arteries
- Diffuse motor-sensory peripheral neuropathy
- _______: painful, asymmetrical, asynchronous sensory and motor peripheral neuropathy involving isolated damage to at least 2 separate nerve areas
A
Vasculitis
- Mononeuritis multiplex
8
Q
Diagnosis?
- Systemic vasculitis characterized by necrotizing inflammatory lesions that affect medium-sized and small muscular arteries
- Clinical presentation: Mononeuritis multiplex, myalgia, abdominal pain, nephropathy, skin ulceration
- Work up: CBC, CCP, ESR, hep panel, hypergammaglobulinemia found in 30% of patients), complement panel
A
Polyarteritis Nodosa
- Skin ulcerations
- Livedo reticularis
FIBRINOID NECROSIS of the ARTERIAL WALL with LEUKOCYTIC INFILTRATE
9
Q
Diagnosis?
- Autoimmune mediated disease resulting in demyelination
- Can also cause secondary axonal loss
- Incidence - 1-3/100K in the US
- Up to 75% are preceded by an infection, immunization, surgical procedure
- Historically - swine flu, most frequently - campylobacter jejuni; also EBV, CMV, lyme, hep, HIV
A
Guillain Barre Syndrome
10
Q
What is the classic presentation of GBS?
- Distinctive absence of Deep tendon reflexes
- Also associated with pain, paresthesia (mid to low back), autonomic instability, respiratory failure
- Sx evolve over 2-4 weeks before reaching a plateau
- Time and extent of recovery is variable; 80-90% return to baseline
- Mortality rate: 5-10% (often respiratory related)
A
Rapidly ascending weakness starting distally in the feet and working proximally - quite variable
11
Q
What are the diagnostic evaluations used to GBS?
- ____ - cytoalbumic dissociation in their CSF
- ____ - nerve conduction studies may show slowed conduction speeds due to segmental demyelination, often normal early-on
Tx:
- Treated with ______ for 5 days or _____ for 5 treatments (every other day)
[equally effective, but not more if combined] - Transient ventilatory support is occasionally needed
- Extensive rehab
A
- LP
- Neurophysiology
Tx:
- IV Ig, Plasma exchange (PLEX)
12
Q
What diagnosis?
- Variant of GBS
- Presents with _____, _____, _______, ______, _______
- Anti-GQ1B antibodies are present in >90% of cases
A
Miller Fisher Variant
- Ophthalmoplegia, ataxia, facial weakness, dysarthria, areflexia
13
Q
Diagnosis?
- Antibody mediated reaction along with interstital and perivascular infiltration of the endoneurium with inflammatory T cells and macrophages – segmental demyelination of peripheral nerves
- Prevalence: 4/100k in the US
A
CIDP
14
Q
CIDP:
- Starts insidiously and evolves slowly; progressive in most but can have a relapsing remitting presentation in ~30%
- Both _____ and _____ symptoms
- _________ can occur –> see orthostatic dizziness, bowel/bladder function problems, cardiac issues
A
Motor and sensory
autonomic system dysfunction
15
Q
How is CIDP diagnosed?
- CSF shows _______
- ____ shows evidence of demyelination
- Biopsy is occasionally needed
How is CIDP treated?
A
- Elevated protein
- EMG/NCS
- Steroids, azathioprine, mycophenolate, cytoxan
- PLEX
- IVIg
