Peripheral Neuropathy

Question 1

Peripheral Neuropathy:

Approach?

Answer 1

*Can be sensory, motor, autonomic or mixed

History:

• clarify the sensation for the patient
• Paraesthesia interpretations = pins and needles, tingling, pricking, formication*
• medications
• prodromal illness
• comorbidities (diagnosed and undiagnosed)
• chemical exposure

Possible causes:

• Idiopathic 25%
• Hereditary 20% -Charcot-Marie Tooth disease (most common)
• Vitamin B1, B6 and B12 deficiencies
• Alcohol
• Local nerve pressure
• Medications:
  
  • amiodarone
  • levodopa
  • statins
  • antiretrovirals
  • tacrolimus
  • nitrofurantoin
• Toxins
  
  • Chemotherapy
  • lead
  • mercury
• Porphyria
• Autoimmune
• DM
• thyroid disease
• BBV - Hep B, C, HIV
• Mononeuritis multiplex (asymmetric signs)
• If no sensory component consider:
• muscular dystrophy
• myasthenia gravis
• myopathy
• Quick onset suggests:
• Guillain Barre Syndrome
• vasculitis
• toxins

Investigation:
-if diagnostic uncertainty then nerve conductions are required

Management:

1) treat underlying cause
2) Replace deficiencies
3) Supports/exercises/surgery for local nerve related compression
4) Medication:
- Pregabalin 25mg BD up to 600 - 900mg
- Amitriptyline
- duloxetine
- venlafaxine