From the Guidelines
Guillain-Barré Syndrome (GBS) and Myasthenia Gravis (MG) are distinct autoimmune neurological disorders with different pathophysiologies, clinical presentations, and treatment approaches. GBS is an acute, rapidly progressing condition where the immune system attacks the peripheral nerves, causing ascending paralysis that typically begins in the legs and moves upward, often following a respiratory or gastrointestinal infection and usually resolving within weeks to months 1. In contrast, MG is a chronic condition characterized by fluctuating muscle weakness that worsens with activity and improves with rest, typically affecting ocular muscles first, resulting from antibodies targeting acetylcholine receptors at neuromuscular junctions 2.
Key Differences
- Pathophysiology: GBS involves demyelination of peripheral nerves, while MG affects neuromuscular junction transmission 3.
- Clinical Presentation: GBS presents with ascending paralysis, while MG presents with fluctuating muscle weakness, typically affecting ocular muscles first.
- Treatment: GBS treatment includes intravenous immunoglobulin (IVIG) at 0.4 g/kg for 5 days or plasma exchange, along with supportive care 1, while MG treatment includes acetylcholinesterase inhibitors, immunosuppressants, and in crisis situations, IVIG or plasma exchange.
Diagnosis and Management
Diagnosis of GBS is mainly based on clinical features, supported by cerebrospinal fluid examination and nerve conduction studies, using criteria such as the National Institute of Neurological Disorders and Stroke (NINDS) criteria and the Brighton Collaboration criteria 3. Management of GBS requires a multidisciplinary approach, including supportive medical care and immunotherapy, with IVIG and plasma exchange being proven and equally effective treatments 1.
Considerations in Low-Income and Middle-Income Countries (LMIC)
In LMIC, diagnosis and management of GBS can be challenging due to limited facilities for cerebrospinal fluid examination and nerve conduction studies, leading to diagnostic delays and under-reporting of GBS 3. Small volume plasma exchange (SVPE) is a novel, relatively low-cost technique for selective removal of plasma, which has been shown to be a safe and feasible treatment for GBS in resource-limited settings such as India and Bangladesh 1.
From the Research
Difference between GBS and MG
The main differences between Guillain-Barré syndrome (GBS) and Myasthenia Gravis (MG) are:
- Clinical Presentation: GBS is characterized by acute or subacute onset of muscular weakness involving the limbs and bulbar muscles, while MG is marked by fluctuating weakness of the voluntary muscles, particularly those controlling eye and eyelid movement, facial expression, chewing, talking, and swallowing 4.
- Electrophysiological Features: GBS is associated with electromyographic (EMG) abnormalities, such as conduction block or temporal dispersion, whereas MG is characterized by a decremental response to repetitive nerve stimulation 4.
- Cerebrospinal Fluid (CSF) Analysis: GBS is typically associated with albumino-cytologic dissociation in CSF, whereas MG does not have specific CSF findings 4.
- Treatment Response: Both GBS and MG respond to immunomodulatory therapies, such as intravenous immunoglobulin (IVIG) and plasma exchange (PE), but the response may vary depending on the disease severity and individual patient characteristics 5, 6.
- Prognosis: The prognosis for GBS is generally good, with most patients recovering fully or partially, whereas MG has a more variable prognosis, with some patients experiencing persistent weakness or requiring ongoing treatment 7, 8.
Key Features of GBS and MG
Some key features of GBS and MG are:
- GBS: + Acute or subacute onset of muscular weakness + Electromyographic (EMG) abnormalities + Albumino-cytologic dissociation in CSF + Positive anti-ganglioside antibodies in serum
- MG: + Fluctuating weakness of voluntary muscles + Decremental response to repetitive nerve stimulation + Positive acetylcholine receptor antibody + Variable prognosis depending on disease severity and treatment response
Coexistence of GBS and MG
The coexistence of GBS and MG in the same patient is rare, but it has been reported in several cases 4, 8. The clinical characteristics of these cases may be variable, and the diagnosis can be challenging due to the overlap of symptoms between the two diseases. Early diagnosis and proper treatment are essential to improve the prognosis of patients with coexisting GBS and MG.