What is Guillain-Barré Syndrome (GBS)?
Guillain-Barré Syndrome (GBS) is a rare autoimmune disorder in which a person’s own immune system mounts an inflammatory response and causes damage to his or her peripheral nerves. This can affect the sensory, motor and autonomic nerves. Symptoms often come on rapidly and can include sensory disturbances in the extremities (hands, arms, feet and legs), muscle weakness and loss of reflexes. In some cases, this muscle weakness can lead to paralysis. In rare circumstances, patients can experience difficulty breathing that leads to respiratory difficulties.
GBS after a flu shot is similar to Chronic Inflammatory Demyelinating Polyneuropathy (CIDP), which also affects the peripheral nerves, but is distinguished by the gradual onset of symptoms and chronic nature of CIDP.
There are several variants of GBS, including acute inflammatory demyelinating polyneuropathy (AIDP), the most common GBS variant in the US. Other variants include Miller Fischer Syndrome (MFS), acute motor axonal neuropathy (AMAN), and acute motor sensory axonal neuropathy (AMSAN).
Although Guillain-Barré syndrome is rare, it does not discriminate amongst the individuals affected, affecting both sexes equally and occuring at any age.
What causes GBS?
While the cause remains unknown, the Genetics Home Reference cites that approximately 50% of cases have been reported to occur shortly after a viral or bacterial infection, and sometimes following infections as common as the flu or food poisoning. GBS has also been reported to occur after receiving the flu vaccination.
After initial clinical manifestations of the disease, symptoms can progress over hours or days, but typically peak within four weeks. Muscle weakness gradually increases during the initial phase, although patients generally see these symptoms peak around the two week mark.
During the secondary phase, signs and symptoms of Guillain-Barré syndrome tend to stabilize. For this reason, the second phase is typically referred to as the “plateau” stage.
In the third and final phase, known as the recovery phase, symptoms can improve. Some people with Guillain-Barré syndrome, however, never fully recover. Typical residual symptoms include excessive fatigue, sensory disturbances, muscle weakness, or muscle pain.
How is GBS related to the flu vaccine?
The CDC cites that between 80 and 160 cases of GBS are diagnosed each week, regardless of vaccination. After several studies suggesting a link between GBS and the influenza vaccine, the Vaccine Injury Table was revised in March of 2017 to include the occurrence of GBS following flu vaccine.
Since making the connection between GBS and the 1976 swine influenza vaccine, several studies have evaluated the relationship between the condition and the seasonal influenza vaccine. Although evidence has not been adequate to accept or reject a causal relationship between the vaccine and the condition, researchers have noted increased chances of contracting GBS both with the 1992-93 and 1993-94 seasonal influenza vaccines.
According to the Vaccine Injury Table, symptoms of GBS should manifest 3-42 days following vaccination to bring an on-Table claim, although it is still possible to file a successful claim if symptoms do not strictly fall within this time period.
How is GBS diagnosed?
Guillain-Barré syndrome is a clinical diagnosis based on presentation of weakness and absent reflexes. However, physicians typically conduct testing to support a diagnosis of Guillain-Barré syndrome, including:
- Lumbar Puncture (used to measure cerebrospinal fluid)
- Electromyography and Nerve Conduction Studies
How is GBS treated?
Because the early stages of GBS are largely unpredictable and symptoms can be severe, most newly diagnosed patients are hospitalized.
Treating GBS can involve the coordinated efforts of a neurologist, physiatrist, internist, family physician, physical therapist, occupational therapist, social worker, nurse, and psychologist or psychiatrist. Some patients may also require speech therapy depending on the extent of the disease’s effects.
Plasma exchange and high dose intravenous immune globulins often assist in shortening the course of GBS if administered in the early stages of the disease. The GBS/CIDP institute finds that over 90% of patients move into the rehabilitative phase within four weeks.
Living with GBS
Patients with Guillain-Barré syndrome not only suffer physical difficulties, but can suffer emotionally painful periods as well. Many patients find it difficult to adjust to sudden paralysis and dependence on others for activities that were previously performed with ease.
The recovery period for GBS may last anywhere from a few weeks to a few years. The National Institute of Neurological Disorders and Stroke cites that 30% of those with Guillain-Barré Syndrome still have residual weakness after 3 years, and 3% may suffer a relapse of muscle weakness and tingling sensations years after the initial attack.