Reye Syndrome

(Reye's Syndrome)

ByM. Cristina Victorio, MD, Akron Children's Hospital
Reviewed/Revised Apr 2025
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Reye syndrome is a very rare but life-threatening disorder that causes inflammation and swelling of the brain and impairment and loss of function of the liver.

  • The cause of Reye syndrome is unknown, but it may be triggered by a viral infection and the use of aspirin.

  • Children typically have symptoms of a viral infection and then severe nausea, vomiting, confusion, and sluggishness, sometimes followed by coma.

  • The diagnosis is based on sudden changes in the child's mental condition and on the results of blood tests and a liver biopsy.

  • Treatment involves measures to lower pressure on the brain.

  • The prognosis depends on how long and how severely the brain is affected.

The cause of Reye syndrome is unknown, although it typically occurs after infection with certain viruses, such as influenza (flu) or chickenpox, particularly in children who take aspirin during these infections. Because of this increased risk of triggering Reye syndrome, aspirin is not recommended for children, except for the treatment of Kawasaki disease.

Now that aspirin use has declined and chickenpox is less common because of vaccination, only about 1 child a year in the United States develops Reye syndrome.

The syndrome occurs mainly in children younger than 18.

In the United States, most cases occur in late fall and winter.

Symptoms of Reye Syndrome

Reye syndrome varies greatly in severity.

The syndrome begins with the symptoms of a viral infection, such as an upper respiratory tract infection, influenza, or sometimes chickenpox. After 5 to 7 days, the child suddenly develops very severe nausea and vomiting. Within a day, the child becomes sluggish (lethargic), confused, disoriented, and agitated. These changes in the child's mental condition are caused by increased pressure within the skull (intracranial pressure) and are sometimes followed by seizures, coma, and death.

In some children, the liver does not function correctly, which may lead to blood-clotting problems and bleeding and a buildup of ammonia in the blood.

Diagnosis of Reye Syndrome

  • Laboratory and imaging tests

  • Biopsy of the liver

Doctors suspect Reye syndrome in children who suddenly develop changes in mental condition and vomiting.

Lab Test
Lab Test

To confirm the diagnosis of Reye syndrome and rule out other diseases, such as certain hereditary metabolic disorders, doctors do blood tests and often remove a piece of liver tissue using a small needle (liver biopsy).

Doctors do computed tomography (CT) or magnetic resonance imaging (MRI) of the head and may also do a spinal tap to obtain cerebrospinal fluid for further testing.

Once the diagnosis is confirmed, the level of severity is staged from 1 (lowest) to 5 (highest) based on the symptoms.

Treatment of Reye Syndrome

  • Measures to lower pressure on the brain

There is no specific treatment for Reye syndrome.

Children are hospitalized and placed in an intensive care unit. To reduce swelling and pressure on the brain, doctors may place a tube into the windpipe (endotracheal intubation), restrict fluids, elevate the head of the bed, and give medications (such as mannitol) that force the body to get rid of water. . To reduce swelling and pressure on the brain, doctors may place a tube into the windpipe (endotracheal intubation), restrict fluids, elevate the head of the bed, and give medications (such as mannitol) that force the body to get rid of water.

Doctors also give dextrose to maintain a normal level of sugar (glucose) in the blood. Doctors also give dextrose to maintain a normal level of sugar (glucose) in the blood.

Occasionally, doctors place a pressure-measuring device inside the head to monitor the increased pressure on the brain.

Children with bleeding problems may be given vitamin K or fresh frozen plasma to improve their blood clotting function.

Prognosis for Reye Syndrome

The child’s prognosis depends on how long and how severely the brain was affected, whether the illness progressed to coma, the severity of increased pressure on the brain, and the level of ammonia in the blood.

Many children who survive the acute phase of the illness recover fully, and Reye syndrome rarely affects a child twice. However, children who had more severe symptoms may later have signs of brain damage, such as intellectual disability, a seizure disorder, or muscle weakness. Abnormal muscle movement or damage to specific nerves may also occur.

Reye syndrome is fatal in about 21% of affected children, but this varies depending on whether the syndrome is mild (stage 1) or severe (stage 4 or 5).

Drugs Mentioned In This Article

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