Peripheral nerve disease - Guillain Barre Syndrome and mononeuropathies

Question 1

Name a mononeuropathy affecting a single nerve

Answer 1

Carpal tunnel

Question 2

Name a process affecting multiple neuropathy

Answer 2

Mononeuritis multiplex

Question 3

Causes of mononeuritis multiplex

Answer 3

Acute

• Daibetes mellitus
• Polyarteritis nodosum
• Connective tissue diseases, e.g. SLE, Rheumatoid arthritis

Chronic

• multiple compressive neuropathies
• sarcoidosis
• acromegaly
• leprosy
• Lyme disease
• idiopathic

Question 4

Causes of painful peripheral neuropathy

Answer 4

Diabetes mellitus

Alcohol

Vitamin B1 or B12 deficiency

Carcinoma

Porphyria

Arsenic or thallium poisoning

Question 5

Cause of peripheral neuropathies

Answer 5

• D Drugs and chemicals (Pb, phenytoin, metronidazole, amiodarone, hydralazine, vincristine, isoniazid, organic solvents, sulphonamides, nitrofurantoin, CO, OPs).
• A alcohol (with or without Thiamine deficiency)
• M metabolic (diabetes, hypoglycemia, uraemia)
• I infection (HIV, leprosy, lyme, diptheria, syphilis) or post infectious (GBS)
• T tumour (paraneoplastic phenomenon – lung, lymphoma, myeloma)
• B B12 & other vitamin deficiency states, as well as pyridoxine excess
• I idiopathic and infiltrative (e.g. amyloidosis)
• T toxins (botulism, ciguatera, Tetrodotoxin, Saxitoxin, BRO, tick paralysis)
• C connective tissue diseases (e.g. SLE, PAN, RhA) and congenital (e.g. CMT)
• H Hypothyroidism

Question 6

Most common causes of peripheral neuropathies

Answer 6

diabetes mellitus

amyloidosis

Guillain-Barre Syndrome

Paraneoplastic neuropathy (usually lung cancer)

Sogren’s syndrome-associated neuropathy

Question 7

What is Guillain-Barre syndrome?

Answer 7

Acute demyelinating polyneuropathy

An acute inflammatory response which most-often occurs several weeks after viral infection, usually GI/GU.

Question 8

How long after infection does paralysis occur in someone with Guillain-Barre syndrome?

Answer 8

1-3 weeks

Question 9

What are causes of Guillain-Barre Syndrome?

Answer 9

Uusually triggered by infection (normally resp or GI infection)

• Campylobacter jejuni
• CMV
• Mycoplasma
• Herpes Zoster
• HIV
• EBV
• Vaccination

Question 10

Why does Guillain-Barre Syndrome occur?

Answer 10

Molecular mimicry, i.e. sharing of homologous epitopes between microorganism liposaccharides and nerve gangliosides (e.g. GM1), is the possible mechanism.

Question 11

What are symptoms/signs of Guillain-Barre syndrome?

Answer 11

LMN lesion

• Aymmetrical ascending muscle weakness
  
  • ​All 4 limbs
• Autonomic dysfunction - Sweating, tachycardia, Hypertension, arrhythmias
• CN involvement
  
  • ​Dysphasia
  • Dysarthria
• Sensory loss
  
  • ​Glove and stocking
• LMN signs

Question 12

How long does it take for someone to enter the recovery phase of Guillain-Barre syndrome?

Answer 12

4-6 weeks

Question 13

What proportion of those with Guillain-Barre syndrome develop respiratory and facial muscle weakness?

Answer 13

20%

Question 14

What investigations might you do in someone with suspected Guillain-Barre syndrome?

Answer 14

• Nerve conduction studies (slow conduction)
• LP

Question 15

What might nerve conduction studies show in someone with Guillain barre syndrome?

Answer 15

Slow conduction

Question 16

What might LP investigation show in someone with Guillain-Barre syndrome?

Answer 16

• Increased protein
• Normal WCC
• Normal Glucose

Question 17

What signs may indicate need for transfer to ITU in someone with Guillain-Barre syndrome?

Answer 17

Respiratory involvement

Question 18

How would you monitor for respiratory involvement in someone with Guillain-Barre syndrome?

Answer 18

4-hourly FVC

Question 19

How would you manage someone with Guillain-Barre Syndrome?

Answer 19

• IVIg - 5 days - 2 weeks (immunosupression)
• DVT prophylaxis - LMWH + compression stockings
• Consider Plasma exchange

GBS:

• Get tracheostomy kit
• Begins in lower extremities
• Start NIV

Question 20

What is the prognosis for someone with Guillain-Barre syndrome?

Answer 20

Good - 85% of individuals make near/complete recovery. Recovery takes time: anywhere between several days to 6 weeks.

Question 21

Typical sequence of events of pathology in onset of Guillain Barre

Answer 21

Acute inflammatory demyelination

Polyneuropathy

Question 22

Name 2 varients of GBS

Answer 22

Chronic Inflammatory Demyelinating Polyradiculopathy - characterised by a slower onset and recovery vesrsion of GBS.

Miller-Fischer Syndrome - Comprises of opthalmoplegia, ataxia, areflexia. Associated with anti-GQ1b antibodies in serum.