Neurology Potpourri — Peripheral Neuropathy - GK Flashcards
(76 cards)
1
Q
The _____ nervous system consists of nerve fibers connecting the rest of the body with the ________ (brain, spinal cord).
A
Peripheral
CNS
2
Q
These connect the head, face, eyes, nose, muscles and ears to brain
A
Cranial nerves
3
Q
These connect the spinal cord to the rest of the body
A
Spinal nerves
4
Q
What four types of nerves does the peripheral nervous system include?
A
- Cranial nerves
- Spinal nerves
- Nerves of extremities
- Cervical, brachial and lumbosacral plexuses
5
Q
___________, ____________ & ________ are the 3 elements of the peripheral nerves.
A
sensory, motor, autonomic
6
Q
Peripheral neuropathy results from damage to ____________
A
any part of the nerve
7
Q
What parts of the nerve can be damaged that would cause peripheral neuropathy?
A
- axon
- body of nerve cell
- myelin sheath
- neuromuscular junction
8
Q
A peripheral neuropathy that affects one nerve
A
Mononeuropathy
9
Q
A peripheral neuropathy that affects several discrete nerves
A
multiple mononeuropathy
OR
mononeuritis multiplex
10
Q
Peripheral neuropathy that affects a plexus
A
plexopathy
11
Q
Peripheral neuropathy that affects a nerve root
A
radiculopathy
12
Q
Peripheral neuropathy is characterized by what?
A
- motor weakness
- sensory loss
AND/OR
- positive sensory symptoms (tingling, burning)
- may also have autonomic symptoms
13
Q
T/F: Peripheral neuropathy is has a gradual onset and slowly progressive course.
A
TRUE
14
Q
T/F: Autonomic symptoms of peripheral neuropathy happen in pts with DM & amyloidosis
A
TRUE
15
Q
T/F: Peripheral neuropathy is usually bilateral & symmetric
A
True
16
Q
T/F: Peripheral neuropathy is characterized by distal involvement
A
True
17
Q
T/F: Etiologies of peripheral neuropathy include hereditary and acquired
A
True
18
Q
What are the hereditary causes of peripheral neuropathy?
A
- Charcot-Marie-Tooth dz (MC)
- Porphyria (rare)
19
Q
What are inflammatory acquired causes of peripheral neuropathy?
A
- Guillain Barre Syndrome
- chronic inflamatory demyelinating polyneuropathy
20
Q
What are infectious acquired causes of peripheral neuropathy?
A
- Lyme disease
- HIV
- herpes
- VZV
- CMV
- EBV
- hepatitis viruses
- chagas dz
- diphtheria
- leprosy
- rabies
21
Q
T/F: Acquired etiologies of peripheral neuropathy include rheumatic reasons + organ failure.
A
TRUE
22
Q
What are other acquired causes of peripheral neuropathy?
A
- endocrine
- GI
- malignancy
23
Q
Vitamin deficiency/excess of which vitamins can cause peripheral neuropathy?
A
- B12
- B1 (thiamine)
- Vitamin B6 (pyroxidine)
- Vitamin E
- Niacin
- Copper
“Mercedes [BBB]ENC”
24
Q
What meds cause peripheral neuropathy?
A
- Abx
- antiretrovirals
- chemo agents
- phenytoin
- thalidomide
25
What **toxins** cause peripheral neuropathy?
- Heavy metals
- industrial or environmental substances
26
Important things to ask when taking **History**
- fam history for **inherited disorders**
27
**T/F:** You must complete a full neuro exam
True
28
What labs should you run if a pt comes in with complaints of peripheral neuropathy?
- CBC
- CMP
- A1C **(DM mc cause)**
- TSH
- B12
- folate
- ESR
- Rf
- ANA
- SPEP
- immunoelectrophoresis or immunofixation
- **urine for Bence Jones Protein**
**\*\*You don't have to order them all\*\***
29
What is the purpose of a **nerve conduction study w/electromyography**?
**differentiates** between **nerve** and **muscle disorders**
**differentiates** between **axonal** and **demyelinating** conditions
30
When would you order **imaging**?
What kind of **imaging** would you order?
If concern for **radiculopathy**
MRI/CT cervical, thoracic +/- lumbar
31
What **7 key questions** would you ask and what is the main thing you are listening for when asking these questions?
1. What systems are involved? **(motor, sensory, autonomic, combination?)**
2. What is the distribution of weakness? **(distal vs. proximal,** **focal/asymmetric vs symmetric)**
3. What is the nature of the sensory involvement? **(temp loss, burning, stabbing pain _(small fiber)_ vibratory or propiocdeptive loss _(large fiber)_**
4. What is the temporal evolution? **(_acute_ = days-4wks, _subacute_ 4-8wks, _chronic_ \>8wks, monophasic, progressive, relapse-remitting)**
5. Is there evidence of upper motor neuron involvement? **(w/o sensory loss or w/sensory loss)**
6. Is there evidence for a hereditary neuropathy? **(fam hx, lack of sensor symptoms despite sensory signs)**
7. Are there are associated medical conditions? (**cancer, DM, conn. tissue dz, autoimmune dz. infection)**
32
**T/F:** _Charcot Marie Tooth dz_ is the **most common** hereditary PN
TRUE
33
Charcot-Marie-Tooth dz is a ______ disorder that starts ________ in life and is a __________ loss of motor and sensory function of ______ & ________ extremeties
**demyelination**
**early**
**progressive**
**upper & lower**
34
What are **clinical presentations** of **CMT**?
- Distal leg weakness **(footdrop)**
**-** foot deformities (**pes cavus** (hyper arch), **hammer toes**)
- muscle atrophy below the knee
- reduced/absent DTRs
- sensory deficits
35
What is the **tx for CMT dz**?
**PT/OT**
**bracing (ankle-foot orthotics)**
36
What is poyphyria?
A **metabolic disorder** caused by **enzyme deficiency** in the **heme biosynthetic pathway.**
37
What are the **3 types of porphyria** associated with peripheral neuropathy?
- **Acute intermittent** porphyria
- **hereditary** coproporphyria
- **variegate** porphyria
38
What is the **inheritance** of porphyria?
autosomal dominant inheritance
39
Porphyria attacks are precipitated by what 3 things?
- medications
- hormonal changes
- dietary restrictions
40
Porphyria presentation
**sharp abdominal pain** followed by **agitation, hallucinations, or seizures.**
_Days later,_ **extremity pain followed by weakness**
**Weakness in arms or legs** _(can affect face & bulbar musculature)_
**Asymmetric, proximal or distal**
41
What is the MC PN in developed countries?
Acquired: Endocrine— **DM (diabetic neuropathy)**
42
What types of polyneuropathy happen in diabetic NP?
_**- MC\***_ distal symmetric sensory or sensorimotor polyneuropathy **(DSPN)**
- **Autonomic** neuropathy
- Diabetic neuropathic **cachexia**
- **Polyradiculo**neuropathy
- **Cranial** Neuropathy
- Other mononeuropathies
**"PDACCO"**
43
What does **autonomic neuropathy** consist of?
- abnormal sweating
- dysfunctional thermoregulation
- dry eyes/mouth
- pupillary abnormalities
- cardiac arrhythmias
- postural hypotension
- GI abnormalities (gastroparesis, postprandial bloating, chronic diarrhea, constipation)
- GU dysfunction (impotence, retrogade ejaculation, incontinence)
44
Risk factors of Diabetic PN?
- long-standing, poorly controlled DM
- retinopathy
- nephropathy
45
What is the **main presentation** of Diabetic PN?
**Sensory loss:**
**+/-** symptoms
starts in toes, progresses over time up legs and into fingers and arms: **"stock-glove"**
**_painless_** injuries
**_NOT_** distributed along a **dermatome/myotome**
46
Describe the motor symptoms associated with Diabetic PN?
distal, proximal or focal weakness
47
Describe the autonomic symptoms of Diabetic PN
Involves **CV, GI, GU** systems & **sweat glands**
- **ataxia** (gait disturbance)
- **gait instability**
- **syncope/near syncope**
**"AGS"**
48
What is charcot foot & what is it associated with?
Recurring mild fxs that cause this deformity
associated with Diabetic PN
49
What 4 things do you do for the PE of Diabetic NP?
vibratory sense
monofilament
DTRs
Strength testing
50
How to diagnose Diabetic PN?
H&P
labs, imaging as needed
51
Treatment of Diabetic NP
- **glucose control**: tx DM, prevent progressino
- foot care **education**
- consider **podiatry referral**
- medications for **pain**
- Medications for **autonomic dysfunction**
52
What meds would you rx for pain for Diabetic PN pts?
anto-epileptics
anti-depressants
Na channel blockers
Other analgesics
53
\_\_\_\_\_\_\_\_\_\_\_ is more commonly associated with **proximal neuropathy than neuropathy**
Hypothyroidism
54
Most common **neuropathic manifestation of hypothyroidism** is \_\_\_\_\_\_\_\_\_\_\_\_
carpal tunnel syndrome
55
What is the treatment for hypothyroidism PN?
treat the hypothryoidism
56
What are examples of acquired GI PN ?
**celiac dz** that does not respond to gluten-free diet
## Footnote
**IBD**
57
Is it possible to get PN with the following **Rheumatic** dzs?
Granulomatosis with polyangiitis **(Wegener granulomatosis)**
eosinophilic granulomatosis with polyangiitis **(Churg-Strauss)**
**immunoglobulin A vasculitis**
**IBD**
**RA**
**Juvenile idiopathic arthritis**
**Sjogren syndrome**
**SLE**
**scleroderma**
**mixed connective tissue dz**
**sarcoidosis**
**polyarteritis nodosa**
Yes, is someone has a rheumatologic or autoimmune condition, they can get PN
58
**T/F:** There is often no vasculitic component to the underlying etiology of rheumatic PN
FALSE; there is often a vasculitic component
59
How does **malignancy** lead to PN?
- from **cancerous invasion** or **compression of nerves**
- paraneoplastic effect
- effect of tx
- from **immune compromise**
- lymphoma
- **multiple myeloma**
60
\_\_\_\_% of pts with renal failure develop polyneuropathy
60
61
**Chronic liver failure** is associated with what type of PN?
**generalized sensorimotor neuropathy:** numbness, tingling, minor weakness in **distal** aspects of primarily **lower limbs**.
62
What does this describe?
**complication of sepsis** and **multiple organ failure**
often presents as **inability to wean patient from ventilator**
critical illness polyneuropathy
63
What type of PN is this describing?
**spirochete infection**, *Borrelia burgdorferi*
Transmitted by **deer tick**, *Ixodes dammini*
neurologic complications occur in **2nd & 3rd stages** of infection and include **facial neuropathy, polyradiculoneuropathy or multiple mononeuropathies**
Lyme Disease
64
What is the most commonly seen PN of lyme dz?
Bell's Palsy
65
The following are causes of...
pernicious anemia
dietary deficiency/avoidance
gastrectomy
gastric bypass surgery
IBD
pancreatic insufficiency
bacterial overgrowth
medication related (H2 blockers, PPIs, metformin)
Vit B12 (Cobalamin) deficiency
66
**Clinical Presentation** of Vitamin B12 (cobalamin) deficiency PN
**Glossitis** (tongue soreness that looks bright red & smooth)
**Paresthesias** that starts with **hand numbness**
**sensory loss** affecting proprioception and vibration
**unsteady gait** due to sensory ataxia
diffuse **hyperreflexia**, **absent achilles reflexes**
**Behavioral changes:** mild irritability, forgetfulness, severe dementia and frank psychosis
67
Diagnostics of B-12 deficiency PN
- Low B-12 level
- anemia and macrocytosis may be absent
- elevated methylmalonic acid
- **elevated homocysteine**
**antibodies to intrinsic factor**
**antiparietal cell antibodies**
68
Treatment of B-12 deficiency PN
- dietary changes if MILD
- Vit B12 supplementation
- 1000 microgram IM weekly x 1 month, then monthly
- 1000 microgram PO daily
69
Prognosis of B-12 deficiency PN?
complete reversal of symptoms not always attained
70
Beriberi dz (dry beriberi references neuropathic symptoms) associated with what?
Thiamine (vit B1) deficiency
71
Etiologies of B1 deficiency **(BeriBeri dz)**
MC: chronic alcohol abuse
recurrent vomiting
total parentaral nutrition (tube feedings)
bariatric surgery
restrictive diets
72
Clinical presentation of BeriBeri (B1 def)
**mild sensory loss** and/or **burning dysesthesias in toes and feet**
**aching and cramping** in lower legs
later: **generalized polyneuropathy** with **distal sensory loss in feet & hands**
73
Treatment of Thiamine (vit B1) deficiency
parenteral thiamine replacement until proper nutrition restored
74
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