The Central vs. Peripheral Nervous System

The nervous system is the body’s headquarters. Your nervous system controls everything you do. It is divided into the central nervous system (CNS) and peripheral nervous system (PNS). The CNS consists of the brain and the spinal cord, while the PNS consists of nerves that exit the spinal cord and go to different parts of the body (Figure 1A). The PNS is made up of sensory and motor nerves. Sensory nerves take information from the body to the brain, and this allows you to feel things. Motor nerves carry instructions from the brain to the muscles, so that you can move. You can think of the spinal cord as a highway that carries information to and from the brain, made of bundles of nerves. Exits on the road are like the nerves that leave and enter the spinal cord and spread across the body to carry information to and from the brain, so that you can move and feel (Figure 1B).

What Causes Guillain-Barré Syndrome?

Guillain-Barré syndrome (GBS) is a disease that affects the PNS—the nerves that are like the exit ramps going all over the body. In the United States alone, around 3,000–6,000 people are affected by this disease every year. To understand GBS, you must first understand neurons and myelin. Nerves are made of cells called neurons that carry information in the form of electrical signals. Therefore, you can think of neurons like wires that are surrounded by a plastic covering that helps the electrical message travel faster.

Antibodies are part of the immune system, and they attach to things they think are foreign invaders, such as the bacteria or viruses that make people sick. In GBS, however, the immune system mistakes the body’s neurons for invaders and the antibodies attack the myelin—specifically, they attack important molecules on the surface of the myelin called gangliosides (Figure 2).

But why does the immune system make this mistake? Many things can lead to GBS, such as a stomach infection with bacteria called campylobacter and viruses such as Zika and COVID-19. When the body is fighting off an infection, it can get confused and mistake the gangliosides for foreign invaders! Antibodies attack and hurt the gangliosides, which disrupts the electrical signal in the nerve. When the nerve’s protective covering is damaged, patients may feel tingling and numbness. When the damage happens to motor (movement-related) nerves, patients can experience weakness and have trouble moving [1].

More About GBS

GBS can appear in both males and females at any age, although it is most common in people 50 or older. Symptoms include trouble breathing, along with tingling or weakness in both legs, trouble walking, and feelings of irritation. The earliest sign is usually losing the ability to move the feet. Then the symptoms slowly move up the body, making it harder to move the arms and face (Figure 3). In children, symptoms may present differently, but most symptoms are the same as those experienced by adults.

Doctors can figure out what is wrong by doing tests, such as a spinal tap, and by using a technique called electromyography (EMG). In a spinal tap, a doctor takes a small sample of the fluid that surrounds the spinal cord. If this fluid has a lot of extra white bloods cells and defense proteins, it can be a sign of GBS. EMG can sense if there is any problem with the electric signals that are sent from the muscles to the spinal cord. It uses small sensors on the muscles to check if the electric signals from the nerves are traveling correctly.

It is very important to receive treatment for GBS as soon as possible. If nothing is done, the muscles in the chest may not be able to move, causing trouble breathing and potentially putting a person’s life in danger.

There are several ways to reduce the risk of getting GBS, such as cooking poultry thoroughly, avoiding food contamination, handwashing, and making sure your vaccinations are up to date.

Treatment and Outlook

Even though there is no cure for GBS, some treatments can make symptoms less severe. As this disease involves the immune system attacking the body’s own cells, some treatments involve immunotherapies that decrease inflammation caused by the immune system. For example, people with GBS can be given a collection of healthy antibodies through their blood. These healthy antibodies can block the bad antibodies from causing harm. Another therapy is plasmapheresis, which can clean the blood of the antibodies that are attacking the myelin, helping to lower symptoms.

There are still studies being done to find new and better ways to improve the lives of those with GBS. One study involves a medicine called Tanruprubart, which is a lab-made protein that works like a natural antibody. It blocks part of the immune system to help prevent it from becoming activated and further damaging the myelin.

Other treatments include physical therapy to help increase strength in the muscles. In one study, a 20-year-old woman went through physical therapy, which led to improved symptoms and a better quality of life. Exercises involved several types of stretches and massages. The patient reported less pain, and she was able to walk a longer distance without needing any help. Other studies have found that Frenkel exercises can help with breathing in patients with GBS. Frenkel exercises help the body remember movements it may have forgotten or struggled to do. These exercises consist of patients repeating simple movements several times while watching their arms and legs move. This helps the brain and body work together better [2]. Most individuals can make significant recoveries with timely treatment. The duration of recovery varies for each person, and in general it can take from a few months to 2–3 years or longer to regain full functionality.

How Does Guillain Barre Vary Across Countries?

Another interesting point about GBS is that there are different types and versions of this disease in different parts of the world. Environment and even temperature changes can account for these variations. For example, in Europe, GBS is more common during the cooler winter and spring seasons, as people are more likely to get sick with viruses that can lead to the development of GBS. Differences in the economy may also play a role, as countries with fewer medical care options and with fewer resources for handwashing, for example, can have more cases of GBS [3]. The symptoms can also vary across countries. For example, in Eastern Asia, GBS seems to affect the eyes more than it does in other parts of the world [4].

Putting it All Together

Guillain-Barré is a brain and nerve condition that impacts the peripheral nervous system by attacking the myelin that covers and protects nerve cells. Even though GBS can seem scary, timely diagnosis and treatments can help patients manage their symptoms. Scientists all over the world are working hard to discover therapies that will improve treatment and care for those with GBS. Remember, GBS can occur with any form of infection, or any time the immune system feels threatened, so it is important to stay up to date on your vaccines—people are more likely to get GBS from infections such as the flu than they are to get it from a vaccine.

Glossary

Central Nervous System: ↑ Part of the nervous system that consists of the spinal cord and brain. Receives sensory information, integrates it, and coordinates a motor response accordingly.

Peripheral Nervous System: ↑ Part of the nervous system consisting of nerves that communicate sensory information from the body to the central nervous system, and motor information from the brain to the body.

Neurons: ↑ Nerve cells that serve as messengers between the body and the brain by utilizing electrical and chemical signals.

Myelin: ↑ A fatty covering that insulates the axon of a neuron, helping electric signals move down the neuron faster.

Antibodies: ↑ These are Y-shaped proteins that are made by the immune system to mark invaders for destruction.

Immune System: ↑ This is the body’s defense mechanism that utilizes organs, proteins, and certain cells to protect the body from invaders.

Immunotherapies: ↑ These are treatments that stimulate the immune system to work against disease.

Plasmapheresis: ↑ This is a type of immunotherapy that helps your immune system to attack bad cells.

Conflict of Interest

The author(s) declared that this work was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

AI Tool Statement

The author(s) declared that Generative AI was not used in the creation of this manuscript.

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