Guillain-Barré syndrome (GBS) is a neurological disorder in which the body’s immune system attacks the peripheral nervous system causing various symptoms such as numbness, tingling and muscle weakness that can progress to paralysis. GBS is currently the most common cause of acute flaccid paralysis and is a major health problem worldwide.
During the acute phase of GBS, symptoms progress until reaching clinical stability (4 weeks). From that moment begins a recovery period that can last more than a year. In the most severe cases, GBS can be fatal.
GBS is considered a rare disease with an incidence that varies from 0.9 to 1.9 cases per 100,000 inhabitants per year, mainly in adult men. The most common subtypes are acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor axonal neuropathy (AMAN).
Currently, there is no curative treatment for GBS, only two therapies that try to reduce the severity of the disease and speed up the patient’s recovery based on the removal of antibodies from the blood (plasmapheresis) or the administration of antibodies intravenously to block the antibodies that cause the disease.
The prognosis is variable, with 5% of patients dying despite treatment and 20% remaining with significant aftermath, compromising their autonomy. On the other hand, a very high proportion of patients with an apparent good prognosis remain with persistent symptoms or aftermath that include weakness, pain, or fatigue, the severity of which correlates directly with the degree of neural loss that occurs in the acute phase. Therefore, there is a great path for developing treatments for GBS that can significantly improve the prognosis of the patient.
Several mechanisms are involved in the pathogenesis of the disease, such as humoral and cellular immune responses, autoantibodies and complement, and activated macrophages and lymphocytes. However, the exact role and temporal sequence in which these immunopathogenic mechanisms appear remain to be elucidated.
In most patients, the disease is preceded by an infectious event that triggers the immune response and triggers the acute onset of neurological symptoms manifesting as limb weakness and areflexia.
This direct link to a previous infection suggests that the driver of the autoimmunity developed in the disease is due to molecular mimicry between the antigens of the infectious agent and the peripheral nerve leading to post-infectious inflammation that enhances nerve damage or blocks nerve conduction.