From the Research
Introduction to Guillain-Barré Syndrome (GBS)
Guillain-Barré Syndrome (GBS) is a rare, autoimmune, acute inflammatory polyradiculoneuropathy that affects all age groups, typically resulting in rapid-onset weakness symmetrically affecting proximal and distal muscles [ 1 ]. Cranial muscles can also be affected, and respiratory muscle weakness requiring mechanical ventilation may occur [ 1 ].
Causes and Risk Factors
The exact causes of GBS are not fully understood, but it is often post-infectious, with various clinical, electrophysiological, and immunological subtypes described [ 1 ]. Recent studies have also suggested a possible association between GBS and mRNA-based vaccination, such as the Pfizer-BioNTech COVID-19 vaccine [ 2 ]. Other risk factors may include preceding infections, vaccinations, and autoimmune mechanisms [ 3 ].
Preventive Measures
There are no established preventive measures for GBS, but avoiding infections and ensuring proper vaccination may help reduce the risk [ 3 ]. However, the potential association between GBS and mRNA-based vaccination highlights the need for continued monitoring and research [ 2 ].
Signs and Symptoms
The clinical presentation of GBS encompasses prodromal symptoms, motor deficits, sensory abnormalities, autonomic dysfunction, and variants such as Miller-Fisher Syndrome and Bickerstaff brainstem encephalitis [ 3 ]. Neurological examination findings include weakness, paralysis, sensory deficits, and reflex changes, while autonomic dysfunction manifests as cardiovascular, respiratory, and gastrointestinal symptoms [ 3 ].
Common Symptoms
- Rapid-onset weakness symmetrically affecting proximal and distal muscles
- Cranial muscle weakness
- Respiratory muscle weakness requiring mechanical ventilation
- Autonomic dysfunction, including presyncopal episodes and constipation
- Sensory abnormalities, such as paresthesias and numbness
Variants of GBS
- Paraparetic GBS, characterized by weakness limited to the lower limbs only [ 4 ]
- Miller-Fisher Syndrome
- Bickerstaff brainstem encephalitis
Treatment Options
The main treatment options for GBS are plasma exchanges (PE) and intravenous immunoglobulins (IVIg) [ 1 ]. PE have been shown to be effective in randomized trials, while IVIg are frequently the preferred option for practical reasons [ 1 ].
Treatment Regimens
- Plasma exchanges: 4 exchanges, except in mildly affected patients where 2 may suffice
- Intravenous immunoglobulins: 2 g/kg, administered over 3-5 days
- Corticosteroids: no evidence for use in GBS [ 1 ]
Dosing and Duration
The dosage of IVIg may be sub-optimal in some patients, and studies are underway to evaluate the usefulness of a second IVIg course in severely affected GBS patients [ 1 ]. The treatment duration varies depending on the severity of the disease and the patient's response to treatment.
Differential Diagnosis and Caveats
GBS can be misdiagnosed or underdiagnosed, especially in its early stages [ 3 ]. A thorough diagnostic evaluation, including clinical criteria, laboratory tests, and nerve conduction studies, is essential to confirm the diagnosis [ 3 ]. Additionally, GBS patients may develop psychiatric symptoms, such as stress reactions and anxiety, which require long-term management strategies [ 5 ].