How should I recognize and manage Guillain‑Barré syndrome in a patient with rapidly progressive symmetric limb weakness, loss of deep‑tendon reflexes, possible sensory changes, and a recent viral or bacterial infection?

Guillain-Barré Syndrome: Recognition and Management

Immediate Recognition and Risk Stratification

Guillain-Barré syndrome should be suspected in any patient presenting with rapidly progressive bilateral ascending weakness, diminished or absent deep tendon reflexes, and a recent infection within the preceding 6 weeks. 1, 2

Key Diagnostic Features

• Bilateral ascending weakness typically begins in the legs and progresses to the arms and cranial muscles over days to weeks, representing the hallmark clinical pattern. 1, 2
• Areflexia or hyporeflexia is present in most patients at presentation and nearly all patients at disease nadir; this finding is critical for diagnosis. 2, 3
• Distal paresthesias or sensory loss frequently precede or accompany the motor weakness. 2
• Recent infection history within 6 weeks (particularly Campylobacter jejuni gastroenteritis, upper respiratory infections, or viral illnesses) is reported in approximately two-thirds of patients. 2
• Pain (muscular, radicular, or neuropathic) affects about two-thirds of patients and may be an early presenting symptom. 1

Critical Life-Threatening Assessment

Immediately assess respiratory function and autonomic stability, as these determine mortality risk and need for ICU-level care. 4

• Respiratory failure develops in approximately 20% of patients and can occur rapidly without preceding dyspnea. 1, 2
• Measure vital capacity, negative inspiratory force (NIF), and maximum inspiratory/expiratory pressures at presentation and serially. 4
• Apply the "20/30/40 rule": patient is at risk of respiratory failure if vital capacity <20 ml/kg, maximum inspiratory pressure <30 cmH₂O, or maximum expiratory pressure <40 cmH₂O. 4
• Single breath count ≤19 predicts need for mechanical ventilation. 4
• Monitor continuously for dysautonomia including blood pressure/heart rate instability, arrhythmias, pupillary dysfunction, and bowel/bladder dysfunction. 1, 4, 2

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Diagnostic Workup

Obtain an immediate neurology consultation for every suspected case of GBS to guide diagnosis and management. 4, 5

Essential Laboratory Studies

• Complete blood count, glucose, electrolytes, kidney function, liver enzymes to exclude metabolic or electrolyte dysfunction as causes of weakness. 4
• Serum creatine kinase (CK) is sensitive though nonspecific; elevation suggests muscle involvement and may indicate the acute motor axonal neuropathy (AMAN) variant. 4

Cerebrospinal Fluid Analysis

• Perform lumbar puncture to assess for albumino-cytological dissociation (elevated protein with normal cell count). 4, 5
• Do not dismiss GBS based on normal CSF protein in the first week, as protein elevation typically develops by the end of the first week and may persist until the third week. 4, 6
• Marked CSF pleocytosis (significant white cell elevation) should prompt reconsideration of the diagnosis and evaluation for alternative conditions. 4

Electrodiagnostic Studies

• Conduct nerve conduction studies and EMG to support the diagnosis and classify the neuropathy pattern (demyelinating vs. axonal). 4, 5
• Look for sensorimotor polyradiculoneuropathy with reduced conduction velocities, reduced amplitudes, temporal dispersion, or conduction blocks. 4
• The "sural sparing pattern" (normal sural sensory nerve action potential with abnormal median/ulnar responses) is typical for GBS and represents one of its most specific electrodiagnostic features. 4
• Electrodiagnostic measurements may be normal when performed early (within 1 week); repeat testing in 2-3 weeks if clinical suspicion remains high. 4

Additional Diagnostic Studies

• MRI of spine with and without contrast to rule out compressive lesions and evaluate for nerve root enhancement/thickening. 4
• Serum antiganglioside antibody testing (e.g., anti-GQ1b) should be considered when Miller Fisher syndrome is suspected (ophthalmoplegia, ataxia, areflexia), but do not wait for antibody results before starting treatment. 4, 5
• Anti-GQ1b antibodies are present in up to 90% of Miller Fisher syndrome cases. 4

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Admission Criteria and Monitoring

Admission Decisions

• Grade 2 (moderate) disease – patients with some limitation of daily activities require neurology consultation and close monitoring. 4
• Grade 3-4 (severe) disease – admit to an inpatient unit capable of rapid transfer to ICU-level monitoring for patients with severe weakness limiting self-care, dysphagia, facial weakness, respiratory muscle weakness, or rapidly progressive symptoms. 1, 4

Monitoring Protocol

• Perform frequent pulmonary function testing with serial vital capacity and NIF measurements. 1, 4
• Daily neurologic examinations to track disease progression and response to therapy. 4
• Continuous electrocardiographic and hemodynamic monitoring to detect autonomic dysfunction. 4
• Assess swallowing and coughing ability to identify aspiration risk. 4
• Check corneal reflex in patients with facial palsy to prevent corneal ulceration. 4

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First-Line Immunotherapy

Intravenous immunoglobulin (IVIg) 0.4 g/kg daily for 5 days (total dose 2 g/kg) is recommended for patients unable to walk unaided within 2-4 weeks of symptom onset. 1, 4, 5

Treatment Options

• IVIg 0.4 g/kg/day for 5 consecutive days (total 2 g/kg) is the preferred first-line treatment. 1, 5
• Plasma exchange (200-250 ml/kg over 4-5 sessions) is an equally effective alternative. 1, 5
• Corticosteroids alone are NOT recommended for idiopathic GBS. 4, 5
• Sequential use of plasma exchange followed by IVIg (or vice versa) has not shown benefit. 4

Treatment Response Expectations

• Approximately 40% of patients do not improve in the first 4 weeks following treatment; this does not necessarily indicate treatment failure, as progression might have been worse without therapy. 1, 4
• Early treatment is recommended, and the fact that weakness is spreading to upper extremities does not indicate treatment failure if this occurs within the expected 2-4 week progressive phase. 1
• Treatment-related fluctuations (TRFs) occur in 6-10% of patients, defined as disease progression within 2 months following initial treatment-induced improvement. 1, 5
• Repeating a full course of IVIg or plasma exchange is common practice for TRFs, although high-quality evidence supporting this approach is lacking. 4

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Supportive Care and Symptom Management

Pain Management

• Use gabapentinoids (gabapentin or pregabalin) or duloxetine for neuropathic pain; these are weakly recommended by guidelines. 1, 5
• Gabapentin can be started concurrently with IVIg without drug interaction. 4
• Encourage mobilization for muscle pain and arthralgia. 1

Medications to Avoid

• Avoid medications that can worsen neuromuscular transmission: β-blockers, IV magnesium, fluoroquinolones, aminoglycosides, and macrolides. 4

Standard Preventive Measures

• Treatment of constipation/ileus. 4
• Standard preventive measures for pressure ulcers, hospital-acquired infections, and deep vein thrombosis. 4

Psychological Support

• Recognize that patients with GBS, even those with complete paralysis, usually have intact consciousness, vision, and hearing. 4
• Screen for anxiety, depression, and hallucinations, which are frequent complications. 4
• Be mindful of what is said at bedside and explain procedures to reduce anxiety. 4

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Distinguishing GBS from Acute-Onset CIDP

Consider changing the diagnosis to acute-onset chronic inflammatory demyelinating polyneuropathy (CIDP) if progression continues after 8 weeks from onset or if the patient experiences three or more treatment-related fluctuations. 4, 5

• This scenario occurs in approximately 5% of patients initially diagnosed with GBS. 4, 5
• Acute-onset CIDP may require different long-term treatment strategies. 5

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Prognosis and Long-Term Management

Expected Outcomes

• 80% of patients regain independent walking ability at 6 months. 1, 4
• Recovery can continue for more than 3 years, with improvement possible even more than 5 years after onset. 1, 2
• Mortality is 3-10%, primarily from cardiovascular and respiratory complications. 1, 2, 3
• Advanced age and severe disease at onset are risk factors for poor outcome. 1, 4

Long-Term Sequelae

• Fatigue is reported in 60-80% of survivors and is a major disabling symptom. 4
• Severe pain affects at least one-third of patients at 1 year and may persist for more than a decade. 4
• Recurrence is rare, occurring in only 2-5% of cases. 1, 4

Rehabilitation

• Arrange a rehabilitation program with a rehabilitation specialist, physiotherapist, and occupational therapist. 1, 4
• Exercise programs (range-of-motion, stationary cycling, walking, strength training) improve physical fitness, walking ability, and independence in activities of daily living. 1, 4
• Monitor intensity to avoid fatigue. 4

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Common Pitfalls and Caveats

• Do not delay treatment while awaiting antiganglioside antibody test results; treatment should be initiated based on clinical suspicion. 4
• Do not dismiss GBS based on normal CSF protein in the first week of illness. 4
• Bilateral simultaneous facial weakness is extremely rare in Bell's palsy and should immediately raise suspicion for GBS. 4
• Marked persistent asymmetry, bladder dysfunction at onset, or marked CSF pleocytosis should prompt reconsideration of the diagnosis. 4
• In children younger than six years, GBS may present with atypical features including irritability, refusal to bear weight, and poorly localized pain before obvious weakness emerges. 4