Guillain-Barre Syndrome



Classical: acute inflammatory demyelinating polyneuropathy (AIDP)

  • most commonly identified form
  • nearly 40% of patients are seropositive for Campylobacter jejuni
  • progressive symmetric ascending muscle weakness
  • commonly, unable to stand or walk despite reasonable strength
  • hyporeflexia
  • cranial nerves may be affected later, e.g. resembling Bell's palsy - oculomotor involvement is rare
  • with or without sensory or autonomic symptoms
  • paresthesia generally begins in toes and fingertips and progresses upward but usually not beyond wrists or ankles
  • sensory loss usually involves proprioception
  • autonomic dysfunction may include tachycardia, bradycardia, dysrhythmias, postural hypotension, urinary retention, gastric dysmotility, facial flushing, hypersalivation, anhydrosis, tonic pupils
  • pain may affect shoulder girdle, back, buttocks, and thighs, and may occur with even the slightest movements

Acute motor axonal neuropathy (AMAN) subtype

  • purely motor
  • seasonal incidence, esp China and Mexico, in children
  • nodes of Ranvier are attacked
  • nearly 70-75% of patients are seropositive for Campylobacter
  • may actually be hyperreflexic
  • relatively good prognosis

Acute motor-sensory axonal neuropathy (AMSAN)

  • acute severe illness also affecting sensory nerves and roots
  • typically adults with both motor and sensory dysfunction, marked muscle wasting, and poor recovery

Miller-Fisher syndrome

  • rare variant
  • typically classic triad of ataxia, areflexia, and ophthalmoplegia
  • begins with acute onset of external ophthalmoplegia
  • ataxia tends to be out of proportion to sensory loss
  • may also have mild limb weakness, ptosis, facial palsy, or bulbar palsy
  • anti-GQ1b antibodies in 90%

Diagnosis - required features

  • progressive, relatively symmetrical weakness of 2 or more limbs due to neuropathy
  • areflexia
  • disease course <4 weeks
  • exclusion of other causes

Diagnosis - supportive features

  • relatively symmetric weakness accompanied by numbness and/or tingling
  • mild sensory involvement
  • facial nerve or other cranial nerve involvement
  • absence of fever
  • typical CSF findings obtained from lumbar puncture
  • electrophysiologic evidence of demyelination from electromyogram

CSF

  • elevated or rising protein levels on serial LPs and <=10 mononuclear cells/mm3 strongly support the diagnosis
  • most patients have elevated protein (>400 mg/L), with normal CSF cell counts
  • normal protein does not rule out GBS

Differential diagnosis

  • spinal cord compression
  • polymyositis
  • motor neurone disease
  • encephalititis
  • myasthenia gravis
  • hypo/hyperkalaemia
  • porphyria with abdominal pain, seizures, psychosis
  • vasculitis neuropathy
  • poliomyelitis with fever and meningeal signs
  • Lyme disease and CMV polyradiculitis
  • critical illness neuropathy