Guillain-Barré Syndrome

Guillain-Barré (GHEE-yan BAH-ray) syndrome (GBS) is a disorder of the immune system that affects a part of the peripheral nervous system, that is, the nerves outside the brain and the spinal cord. It is also called acute inflammatory demyelinating polyneuropathy (AIDP) or Landry's ascending paralysis.

There are four different types of GBS: acute inflammatory demyelinating polyneuropathy * (ADIP), which accounts for about 80 percent of all cases; acute motor axonal neuropathy (AMAN), which is similar to ADIP but the patient does not have the sensory symptoms; acute motor sensory axonal neuropathy (AMSAN), which is a severe type of GBS more common in Asia and Central and South America; and Miller Fisher syndrome, which is characterized by double vision and loss of balance and deep tendon reflexes.

GBS is rare, affecting fewer than 2 in 100,000 people in the United States each year.

The exact cause of GBS is unknown. It is theorized that GBS is an autoimmune disease, which means that the body's immune system attacks the body damaging the myelin sheath that covers and protects the nerves, resulting in numbness of the nerves and muscle weakness. Between onehalf and two-thirds of the cases have occurred shortly after a bacterial or viral infection, specifically a gastrointestinal or respiratory illness. In 1976, there was an outbreak of GBS in people who had received the vaccine against the swine flu * , suggesting that the vaccination triggered the onset of GBS. In 2016, studies found that an increase in incidence of Guillain-Barré syndrome in South America was related to the spread of the Zika virus in that area.

Anyone can develop GBS, but it is more common in older adults, with the greatest risk being in people over age 50. One of the most common risk factors for GBS is infection with the bacterium Campylobacter jejuni. Other people who developed GBS reported developing symptoms after having the flu or other infection such as Cytomegalovirus * and EpsteinBarr virus * .

Symptoms of GBS usually begin about five days to three weeks after a mild infection, surgery, or a vaccination * . Signs and symptoms of GBS include the rapid onset of weakness, often accompanied by numbness and tingling sensations. This may lead to paralysis * of the legs, arms, breathing muscles, and face. Paralysis tends to start in the lower limbs, at the toes, feet, and legs, and then move up to the fingers, hands, and arms toward the central part of the body. This is referred to as ascending paralysis. Normal nerve reflexes are decreased or absent. The weakness may progress to where the patient has difficulty breathing, swallowing, eating, drinking, or making facial expressions. The weakness associated with GBS usually worsens over three to four weeks and then stabilizes or gradually returns to normal. It may take a year or more for symptoms to completely disappear.

Usually diagnosis is made based on the history of rapid onset of weakness with the pattern of progression from the lower limbs to the upper limbs to the central torso. To confirm the diagnosis of GBS, the doctor will do a procedure called a lumbar puncture, also called a spinal tap * . A small needle is inserted into the spinal column and a spinal fluid specimen is withdrawn. The spinal fluid is examined for protein. A high level of protein in the spinal fluid is indicative of GBS. An electrical test of nerve and muscle function (electromyogram * * may also be done.

Most patients diagnosed with GBS are treated in the hospital where respiratory (lungs) and cardiac (heart) functions can be monitored and supported. If the progression of the disease affects the person's ability to breathe, a ventilator * may be used to support normal respiration. Because GBS is a disease of the immune system, immune globulin or plasma exchange may be done to bolster the patient's immune system.

Much of the treatment for GBS is supportive: maintaining hydration and nutrition, preventing pressure sores and injuries caused by the inability to move oneself (e.g., urinary tract infection, constipation * , muscle atrophy * ), and psychological and social support for both the patient and their family. Physical therapy may be ordered to assist in maintaining muscle tone and preserving joint mobility.

The damage caused by GBS usually stops progressing and starts to reverse within eight weeks. Approximately 30 percent of adults with GBS have continued weakness for as long as three years after the onset of the disease.

See also Bacterial Infections • Paralysis • Viral Infections • Zika Virus Infection

* polyneuropathy is degeneration (pathy) of many (poly) peripheral nerves (neuro) throughout the body at the same time.

* swine flu is a strain of flu virus that started in pigs that causes respiratory infection in humans.

* Cytomegalovirus is a genus of viruses in the order Herpesvirales, found in monkeys and humans.

* Epstein-Barr virus (EP-stine-BAHR VI-rus) is a common virus that causes infectious mononucleosis.

* vaccination (vak-sih-NAY-shun) is giving, usually by an injection, a preparation of killed or weakened germs, or a part of a germ or product it produces, to prevent or lessen the severity of the disease caused by that germ. Also called immunization.

* paralysis (pah-RAHL-uh-sis) is the loss or impairment of the ability to move some part of the body.

* spinal tap is a medical procedure in which a needle is used to withdraw a sample of the fluid surrounding the spinal cord and brain. The fluid is then tested, usually to detect signs of infection, such as meningitis, or other diseases. Also called a lumbar puncture.

* electromyogram (ee-lek-troMY-eh-gram) (EMG) is a visual record made by an electromyograph, which measures the electrical activity associated with functioning muscle.

* MRI (short for magnetic resonance imaging) produces computerized images of internal body tissues based on the magnetic properties of atoms within the body.

* ventilator (VEN-tuh-lay-ter) is a machine used to support or control a person's breathing.

* constipation is the sluggish movement of the bowels, usually resulting in infrequent, hard stools.

* muscle atrophy is a decrease in muscle mass usually related to not using the muscle group or groups; also called muscle wasting.