Guillain-Barré Syndrome: When to Suspect, What to Rule Out

Medscape

14-05-2025

The Task Force of the European Academy of Neurology and the Peripheral Nerve Society published updated guidelines in 2024 on the diagnosis and treatment of Guillain-Barré syndrome (GBS), which accounts for approximately 100,000 cases annually. This topic was discussed at the French Language Neurology Days Congress, held in Clermont-Ferrand, France, from 15 to 18 April 2025.
The report highlighted that certain infections, particularly those caused by Campylobacter jejuni, could trigger GBS. Furthermore, 'several studies suggest an increased risk following treatments that is associated with immunity, including certain biotherapies such as checkpoint inhibitors or tacrolimus and certain vaccines, such as those for influenza, shingles, or adenoviral vector vaccines against SARS-CoV-2,' summarised Armelle Magot, MD, neurologist at Nantes University Hospital, Nantes, France.
The Task Force concluded that the benefits of these vaccines outweigh the rare risk of developing GBS.
Diagnostic Criteria
The Task Force reviewed various diagnostic criteria proposed in the literature and recommended using the criteria defined in a review published in 2019 as a diagnostic foundation. Key indicators include progressive limb weakness, areflexia or hyporeflexia in the affected areas, and worsening symptoms over more than 4 weeks. Clinical criteria, such as a recent history of infection, cranial nerve involvement, signs of autonomic dysfunction, respiratory failure, or radicular or muscular pain, can further strengthen the diagnostic suspicion. Conversely, certain factors may suggest a differential diagnosis: Persistent asymmetrical weakness, absence of early progression in the initial hours of GBS, predominant sensory signs, fever, and initial disturbances of consciousness.
Biologically, serum levels of anti-ganglioside antibodies are generally not necessary, as their diagnostic sensitivity is limited, except in certain conditions, such as Miller Fisher syndrome. Analysis of the cerebrospinal fluid is recommended to rule out uncertain or differential diagnoses. Protein levels without marked hypercellularity are common in GBS, but they are not reliable, and a normal concentration does not exclude the diagnosis, particularly in the first week.
However, the presence of a significant white blood cell count (< 50/µL) in the cerebrospinal fluid suggested an alternative diagnosis. Finally, electromyography is a valuable tool for diagnosis, while MRI and ultrasound are more commonly employed in atypical cases to rule out certain differential diagnoses.
Management Protocol
The Task Force reaffirmed the role of intravenous immunoglobulins (0.4 g/kg/d for 5 days) or plasmapheresis (4-5 sessions over 1-2 weeks) as first-line treatments.
The Task Force did not favour one treatment over the other, except for intravenous immunoglobulins in children, recognising that the combination of both has no added benefit.
The therapeutic decision is based on the severity of the condition: Treatment should be administered within the first 4 weeks if the patient is unable to walk 10 metres without assistance (GBS disability score ≥ 3). If the patient can walk but cannot run, these treatments may be considered between 2 weeks and 4 weeks if associated severity criteria are present with rapid adverse progression, swallowing difficulties, and so on.
Treatment is not recommended for patients with less severe symptoms or those who are asymptomatic without signs of severity.
Fluctuations related to treatment may occur in 5%-15% of patients, corresponding to relapses during the plateau phase or after initiating the recovery phase. In such cases, retreatment may be proposed following the same modalities.
'Unfortunately, if no improvement is observed after a week, no second-line treatment can be proposed,' said Aude-Marie Grapperon, MD, neurologist at Marseille University Hospital, Marseille, France. In a clinical trial, the second course of intravenous immunoglobulins showed poor benefit, and, conversely, thromboembolic adverse effects were observed. Corticosteroids are also ineffective, as numerous clinical trials have confirmed their lack of efficacy when used alone or in combination.
Innovative Treatments
Innovative treatments are currently being evaluated and could provide alternatives for severe forms of the disease. The scientific rationale for these treatments primarily revolves around the early activation of the complement pathway, which is significant in GBS:
Eculizumab, a monoclonal anticomplement antibody, has been studied in this context with two encouraging phase 2 studies; however, phase 3 published data indicated no benefits.
C1q inhibitors: A phase 1 study demonstrated a favourable safety profile, and the results of a phase 3 study conducted in Asian countries have not yet been published but are reported to be positive.
Efgartigimod vs intravenous immunoglobulins is currently in a Phase 2 trial in the United States, which began in September 2024.
Imlifidase, an enzyme derived from Streptococcus pyogenes that cleaves immunoglobulin G, functions as a form of chemical plasmapheresis.
Open-label studies have suggested a favourable safety profile; however, these findings require validation and publication.
Finally, it is essential not to overlook all supportive treatments, such as the treatment of pulmonary infections, psychological support, pain management, and other interventions, which are crucial for the overall improvement of patients.
This story was translated from Univadis France using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.