Peripheral Neuropathy

Question 1

list 5 conditions associated with carpal tunnel syndrome

Answer 1

1) hypothyroidism
2) pregnancy in the third trimester
3) rheumatoid disease
4) acromegaly
5) amyloid (inc in dialysis patients)

Question 2

treatment of MG

Answer 2

acetylcholine esterase inhibitors (pyridostigmine)
IV Ig plasma exchange
Immunosuppressants

Question 3

name 3 autoimmune disorders of the nueromusclar junction

Answer 3

LEMS
neuromyotonia
Myasthenia Gravis

Question 4

Lambert Eaton Myasthenic syndrome is associated with which type of cancer

Answer 4

60% is associated with small cell lung cancer and infact may precede diagnosis by 4 years

Question 5

presentation of LEMS

Answer 5

very rare
causes hyporeflexia and weakness that can be transiently imroved through exercise
caused by antibodies against voltage gated calcium channels

Question 6

presentation of neuromyotonia

Answer 6

very rare
hypertonic stiffness in muscles
cramps
myokymia
caused by antibodies against voltage gated potassium channel which prevents the swithc off of ACh release

Question 7

presentation of myasthenia gravis

Answer 7

uncommon
fatiguable weakness
EYE - diplopia and weakness of eye closure
BULBAR - speech swallowing chewing difficulty smiling
NECK- extension weakness
proximal limb muscle weakness
caused by antibodies against around 80% ACh receptors preventing adequate end plate potentials

Question 8

what is early onset myasthenia graves associated wtih

Answer 8

young women (menarche - 40)
Thymic hyperplasia

Question 9

what is later onset MG associated with

Answer 9

older men

atrophic thymus

Question 10

which tumour is myasthenia graves associated wtih

Answer 10

thymoma at any age

Question 11

sensory signs of nerve dysfunction

Answer 11

numbness 
buring
ataxia
allodynia
reduced proprioception
areflexia

Question 12

motor signs of dysfunction

Answer 12

weakness
wasting
fasciulation
areflexia

Question 13

what is mononeuropathy multiplex

Answer 13

nerve damage involving one or more nerve trunks
usually asymmetrical
(eg in diabetes, leprosy, vasculitis)

Question 14

what is Wallerian degeneration

Answer 14

degeneration of nerve fibres distal to axon separation from cell body

Question 15

what is poly neuropathy

Answer 15

neuropathy involving multiple nerve trunks
symmetrical and usually starts distally

eg GBS sock and glove

Question 16

what is mononeuropathy

Answer 16

single nerve involvement from a local cause

eg trauma or compression

Question 17

what is neuropathy

Answer 17

a pathological process that damages a nerve producing signs and symptoms

Question 18

symptoms of axonal degeneration

Answer 18

tingling
burning
weakness
loss of motor function

Question 19

give examples of acute and chronic demyelinating neuropathies

Answer 19

acute- GBS

chronic - Chronic inflammatory demyelinating polyneuropathy

Question 20

first presentation of GBS

Answer 20

sock and glove neuropathy

Question 21

Treatment of GBS

Answer 21

IV Ig (decreases duration)
plasma exchange (eliminate pathogen)
supportive care

Question 22

most common precursor to GBS

Answer 22

Campylobacter pylori

Question 23

presentation of peripheral neuropathy

Answer 23

tingling
numbness of digits
weakness of limbs
hyporeflexia
fatigue
abnormal sensation

Question 24

3 causes of axonal degeneration

Answer 24

diabetes
alcoholism
genetics (CMT, leprosy)

Question 25

what is Charcot Marie Tooth syndrome

Answer 25

a genetic condition where axonal degeneration is caused by multiple gene mutations for proteins in myelin schwann cells and axons

Question 26

name an anaesthetic which works by blocking sodium channels

Answer 26

lidocaine

Question 27

name an anticonvulsant which works by using sodium channels

Answer 27

carbamezine

Question 28

name 3 excitatory neurotransmitters

Answer 28

noradrenaline - used in the Symp ANS adrenaline - NA agonist Acetylcholine - post ganglionic para NS and in motor end plates

Question 29

signs and symptoms of autonomic neuropathy

Answer 29

``` dry mouth/eyes syncope GI disturbance bladder urgency/frequency impotence dry skin and excessive/inadequate sweating pupil constriction ```

Question 30

what is "dying back" neuropathy

Answer 30

distal axonal degeneration often due to toxic/metabolic abnormalities of neuronal cell body (HIV/AIDS; alcohol etc) starts peripherally and dies back towards the cell body

Question 31

aetiologies of chronic peripheral neuropathy

Answer 31

variable: - idiopathic - diabetes/impaired glucose tolerance - drugs (statins, cytotoxic drugs) - B12 deficiency - alcohol - inherited

Question 32

presentation of radial nerve compression neuropathy

Answer 32

wrist drop and weakness of brachoradialis

Question 33

presentation of ulnar nerve compression at the elbow

Answer 33

hypothenar wasting weakness of finger abduction and opposition of little finger sensory changes in medial 1.5 fingers

Question 34

presentation of carpal tunnel syndrome

Answer 34

numbness in lateral digits waking at night weakness of thumb abduction wasting of thinner eminence

Question 35

presentation of malaria parasthetica

Answer 35

numbness/burning over anterolateral thigh following sudden increase in weight, surgery or injury

Question 36

presentation of compression neuropathy of the common perennial nerve around the fibula

Answer 36

foot drop and weakness of ankle eversion with preserved ankle jerk numbness on anterolateral dormer of the dorsum of the foot follows prolonged sitting/bed rest

Question 37

features of CIDP

Answer 37

- slow onset and recovery - progressive/relapsing procimal and distal limbe weakness and sensory loss - CSF protein raised (>0.4)

Question 38

thiamine deficiency causes which syndrome

Answer 38

Wernicke-Korsakoff - abnormal eye movements (nystagmus, bilateral L rectus palsy, conjugate gaze palsies) - ataxia (broad based gait, cerebellum signs and vestibular paralysis) - cognitive change (acute stupor/coma followed by amnesic syndrome and confabulations)

Question 39

which vitamin deficiency neuropathy presents as: tingling and numbness of fingers and toes distal sensory loss (esp in dorsal column) absent ankle jerks exaggerated knee jerks and extensor plantear response

Answer 39

B12 Cobalamin

Question 40

what are the causes of peripheral neuropathy

Answer 40

``` Diabetes Alcoholism Vitamin deficiency Infective/inherited Drugs (e.g. isoniazid) ```

Question 41

name 6 methods of peripheral nerve damage

Answer 41

demyelination axonal degeneration (usually toxic neuropathies) wallerian degeneration (crush injuries) compression infarction (polyarteritis nodosa, Churg-Strauss) infiltration (leprosy, malignancy, inflammation, sarcoidosis)

Question 42

mixed upper and lower motor neurone signs is indicative of which group of conditions

Answer 42

motor neurone disease 75% have symmetrical weakness and wasting usually painless 25% bulbar and pseudo bulbar features (eye movements usually spared) there is NO sensory loss sphincters are NOT affected

Question 43

which tracts are affected by ALS

Answer 43

lateral corticospinal tracts causing a spastic paraparesis