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Definition
Group of neuropathic conditions characterized by progressive weakness & dimished or absent reflexes.
Inflammatory neuropathy due to cross reactivity between neural antigens & antibodies induced by specific infections Campylobacter (most common) but also
reported following: Mycoplasma Pneumoniae, Hemophilus Influenza, CMV, EBV
Epidemiology
Estimated annual incidence in the United States is 1.65 to 1.79 per 100,000 persons
Incidence increases from 0.62 per 100,000 in those <9 years old to 2.66 per 100,000 in those 80-89 years old
Male-to-female ratio is 3:2
Preceding illness
Most common symptoms reported before onset of Guillain-Barré Syndrome are: fever, cough, sore throat and other upper respiratory symptoms
Infection with Epstein-Barr virus has been linked to milder forms of Guillain-Barré Syndrome
GI symptoms may be more likely to precede Guillain-Barré subtypes that are related to slower recovery and higher risk of residual disability
Guillain-Barré Syndrome Subtypes
Acute inflammatory demyelinating polyradiculopathy Multifocal peripheral demyelination, slow remyelination,
both humoral and cellular immune mechanisms Most common subtype (90% of Guillain-Barré Syndrome in
the US)
Acute motor axonal neuropathy Antibodies against gangliosides GM1, GD1a, GalNAc-GD1a
and GD1b in peripheral motor nerve axons 5-10% of GBS cases Only motor symptoms
Acute motor-sensory axonal neuropathy Similar to acute motor axonal neuropathy but with sensory
axonal degeneration, predominantly sensory involvement
Guillain-Barré Syndrome Subtypes
Miller Fisher syndrome Demyelination, immunoglobulin G antibodies against
gangliosides GQ1b, GD3 and GT1a Rare, 3% of GBS cases in US Bilateral opthalmoplegia, ataxia, areflexia, facial & bulbar
weakness in 50% of cases Trunk, extremity weakness occurs in 50% of cases
Acute autonomic neuropathy Mechanism is unclear Autonomic symptoms, sensory loss Recovery is slow and may be incomplete
Presentation
Presentation: Symmetrical weakness (ascending) Decreased or absent reflexes
Also commonly seen: Weakness, numbness, tingling & pain in the
limbs 25% of patients will have advancing weakness
that compromise the respiratory muscles- will require mechanical ventilation
Presentation
Respiratory failure is more common in patients with rapid progression of symptoms, upper limb weakness, autonomic dysfunction or bulbar palsy
Facial, oropharyngeal & oculomotor muscles may be affected because of cranial neuropathy
Autonomic symptoms include arrythmias, orthostasis, BP instability, urinary retention, decreased GI motility
Pain is reported in 50-89% of Guillain-Barré Syndrome patients Pain is severe, deep, aching or cramping in muscles or back Difficult to control because pain is nociceptive and/or neuropathic
Diagnosis
Clinical criteria for diagnosis include: Symmetric motor weakness (bilateral symptoms) Absent or decreased reflexes
Lumbar puncture: Elevated protein in CSF, normal WBC count Protein level may be normal in the 1st week of symptoms,
protein will be elevated in 90% of cases by then end of the 2nd week
Nerve conduction studies: Slowed conduction (<60% normal velocity) or blockage of
nerve conduction will be seen Must test at least 3 motor nerves & 3 sensory nerves, must
avoid sural nerve (often normal in GBS) Can be used to track progression of the illnes
Differential Diagnosis
Brainstem: Infection, stroke
Spinal cord: compression, myelopathy, poliomyelitis, transverse myelitis
Rhabdomyolysis
Myasthenia gravis
Toxicity: industrial chemicals and other toxins
Infectious, inflammatory or toxic myopathy
Lyme disease
Complications
Neuropathic pain
Autonomic dysfunction Hypotension, hypertension, arrythmias,
bladder and bowel dysfuntion
Increased risk of VTE
Bulbar dysfunction & swallow difficulty, risk of aspiration
Complications
Respiratory failure Close respiratory monitoring with frequent
measurement of negative inspiratory force (NIF) should be instituted initially on all all Guillain-Barré Syndrome patients
NIF is a noninvasive method to measure respiratory muscle strength
Acceptable NIF range in Guillain-Barré Syndrome is -20 to -40 at least
Normal NIF is more negative than -60
Complications
Predicts the need for mechanical ventilation
Bulbar symptoms
Inability to raise the head or flex the arms
Inadequate cough
Maximum expiratory pressure: < 40 cm H2O
Maximum inspiratory pressure: < 30 cm H2O
Vital capacity: < 60 percent of predicted or < 20 mL per kg
Vital capacity, maximum inspiratory pressure, or maximum expiratory pressure reduced by at least 30 percent
Treatment
Disease modifying therapy: IVIg- 400mg/kg/day x 5days OR 2g/kg/day x 2days Plasma exchange (Plasmapheresis) – optimal response
if performed within 7 days onset
Both IVIg and plasma exchange are equally effective according to the literature but combining them is not beneficial
Mild Guillain-Barré syndrome cases benefit from 2 sessions of plasma exchange
Severe disease often requires 4 sessions
Corticosteroids are not recommended and may in fact delay long term recovery
Treatment
Initial response to IVIg does not predict the outcome because patients may stabilize or continue to decline after therapy
Treatment
Supportive care
SQ anticoagulation & SCD’s to reduce risk of VTE
Swallow eval in patients with facial or oropharyngeal weakness- risk of aspiration
ICU monitoring- ANS dysfunction and risk of respiratory failure, patient can become very unstable very quickly
Treatment
Bladder & bowel care Foley catheter, enemas & laxatives, erythromycin for
treatment of ileus
ANS dysfunction Paroxysmal HTN (24%), Orthostatic hypotension (19%),
sustained HTN (3%) Severe HTN- use PRN Labetalol, Esmolol, Nitroprusside Hypotension- IV fluid boluses 1st, then low dose phenylephrine
Arrythmias Sustained sinus tachycardia (37%)- requires no treatment Bradycardia & asystole (4%)
Treatment
Patients with limited mobility should be closely monitored for skin breakdown and treated appropriately
Pain control- neuropathic pain in 40-50% of patients Gabapentin (Neurontin) Carbamazepine (Tegretol) NSAIDs TCA’s Tramadol Epidural morphine
Treatment
Physical therapy and rehabilitation is recommended to decrease residual deficits and increase speed of recovery
A supervised exercise program is also recommended to improve fatigue as well as functional abilities
Prognosis
Even with appropriate treatment, 3% of patients with Guillain-Barré Syndrome will die
25% of patients will require mechanical ventilation which increases mortality risk
Prognosis is worse in patients with rapid onset of symptoms, severe symptoms and in elderly patients
Neurological deficits persist in 20% of patients, half of these remain severely disabled
Up to 80% of patients experience persistent, severe fatigue after resolution of other symptoms
Prognosis
Predicts long-term disability
Absence of motor response
Diarrheal illness
Axonal involvement
Campylobacter jejuni or cytomegalovirus infection
Inability to walk at 14 days
Older age
Rapid progression of symptoms
Severity of symptoms at their peak
CME Questions
Q: A patient presents with leg pain. Which one of the following accompanying findings most consistently suggests Guillain-Barré syndrome? (check one)
A. Prominent bowel or bladder symptoms.
B. Cerebrospinal fluid leukocytosis.
C. Relatively symmetrical weakness of the limbs.
D. Normal results on nerve conduction studies.
CME Questions
Q: Which one of the following statements about disease-modifying therapy for Guillain-Barre syndrome is correct? (check one)
A. Plasma exchange should be witheld for the first 30 days after symptom onset.
B. Intravenous immune globulin therapy should be started within two weeks of symptom onset, and should be considered for patients who are nonambulatory.
C. Most patients require six sessions of plasma exchange.
D. Corticosteroids are first-line treatment.
CME Questions
Answer: B. Intravenous immune globulin therapy should
be started within two weeks of symptom onset, and should be considered for patients who are nonambulatory.