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Detailed information of GUILLAIN-BARRE SYNDROME
GUILLAIN-BARRE SYNDROME
DEFINITION:
An acquired demyelinating disorder of the peripheral nervous
system characterized by progressive motor weakness and areflexia.
EPIDEMIOLOGY:
- incidence: 0.6-1.9/100,000 (adult & childhood cases)
- age of onset:
- patients are <20 years of age in 30% of cases
- 2/3rds of these are in children <8 years of age
- rare in children <2 years of age
- risk factors:
- M > F (3:2)
- season: fall and winter
PATHOGENESIS:
- 50-70% of cases occur within 4 weeks of an antecedent illness
(usually an upper respiratory tract infection or GI infection by
CMV or EBV) -> autoimmune response towards peripheral nerves (via
cell- and humorally-mediated immune mechanisms) -> focal areas of
inflammation and demyelination of motor (+/- sensory) nerves -
also may occur after hepatitis, immunizations, insect stings,
surgery, viral exanthems, and other illnesses
- Campylobacter jejuni and Mycoplasma pneumoniae have been
implicated
PATHOLOGY:
- widespread areas of focal inflammation and demyelination
- most common
- proximal nerve roots at junction of dorsal & ventral nerve
roots at the site of dural attachment
- less common
- lumbar and brachial plexuses
- peripheral and cranial nerves
- rarely affected
- dorsal root or ganglia
- sympathetic chain
2. Inflammatory Response
- inflammatory cells: macrophages and lymphocytes
- these cells attack the myelin sheath of Schwann cells
leaving the Schwann cells and axons undisturbed
- complications:
- surrounding axons may be secondarily injured in areas of
intense inflammation causing chromotolysis and neurono-phagia
of the anterior horn cells
- inflammation at sites of dural attachment may cause
breakdown of the blood-brain barrier resulting in transudation
of plasma proteins into the CSF
- insertion of macrophages beneath the lamellae of the
myelin sheath stripping away long sections -> focal
demyelination
- -> conduction block
CLINICAL FEATURES:
- usually ascends from legs to arms and may involve truncal
and finally bulbar musculature (rarely descends)
- may present as a disturbance of gait or acute ataxia
- symmetrical with weakness greater distally than proximally
- may lead to transient quadriplegia
- respiratory paralysis in 18%
- cranial nerve palsies in 30-40%:
- 7th - facial diplegia most common
- 9&10 - dysphagia 2nd most common
- all may be involved rarely except the olfactory nerve
- if extraocular muscle involvement think of Miller-Fisher
syndrome
2. Reflexes
- symmetric areflexia or marked hyporeflexia
- may be mildly asymmetric initially
- may rarely precede motor weakness or may be a late finding
3. Sensation
- loss of position and vibratory sensation
- occasionaly pain or parethesias
- insidious symptoms may precede motor weakness
4. Autonomic Dysfunction
- bowel and bladder dysfunction
- transient and not seen at onset
- cardiovascular instability:
- hypertension, orthostatic hypotension, tachyarrhythmias
INVESTIGATIONS:
- dissociation of elevated protein with lack of cellular
response is highly suggestive of Guillain-Barre syndrome
- elevated protein
- may be undetectable in 1st week of illness
- often peaks at 3-4 weeks
- proteins similar to those in plasma as well as Ig's and
oligoclonal bands
- slight pleocytosis (<10 cells/ul)
2. Electrodiagnostic
- may be reduced to 60% of normal
- detected in 50% during first 2 weeks
- " 85% during 3rd week
- due to segmental demyelination -> conduction block
- may involve motor and sensory nerves
- distal > proximal initially (in 1st week)
2. Somatosensory Evoked Responses
- altered reflecting proximal root involvement
3. EMG
- no changes except decreased recruitment pattern
MANAGEMENT:
- may be beneficial in children with rapid deterioration or
in those needing intubation
2. Supportive
- in an ICU setting
- Peaditrician, Intensivist, Neurologist, OT, PT, Psychology
- moniter neuromuscular, respiratory, cardiovascular status
2. Intubation
- indications for
- respiratory distress/failure
- cardiovascular instability
- decrease in vital capacity to 50% of normal
- progression to dysphagia, shoulder or facial paresis may
indicate need for intubation
- usual duration: 2-8 weeks with consideration of
tracheostomy with lack of improvement after 2 weeks
3. Prognosis
- usually a benign clinical course with recovery with 2-3
weeks with recovery of muscle function inversely related to
onset of symptoms (i.e., bulbar -> arms -> legs)
- complete recovery:
- 50% within 6 months
- 60-70% within 12 months
2. Complications
- 10% with permanent deficits
- 7% will relapse
- 3-4% mortality
- chronic forms of Guillain-Barre:
- Chronic Relapsing Polyradiculoneuropathy
- Chronic Unremitting Polyradiculoneuropathy
3. Poor Prognostic Indicators
- extensive denervation on EMG
- increased duration of time from maximal deficit to onset
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Pediatric Database - GUILLAIN-BARRE SYNDROME
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