Overview

Reye's (Ryes) syndrome is a rare but serious condition that causes swelling in the liver and brain. Reye's syndrome most often affects children and teenagers recovering from a viral infection, most commonly the flu or chickenpox.

Signs and symptoms such as confusion, seizures and loss of consciousness require emergency treatment. Early diagnosis and treatment of Reye's syndrome can save a child's life.

Aspirin has been linked with Reye's syndrome, so use caution when giving aspirin to children or teenagers. Though aspirin is approved for use in children older than age 2, children and teenagers recovering from chickenpox or flu-like symptoms should never take aspirin. Talk to your doctor if you have concerns.

Symptoms

In Reye's syndrome, a child's blood sugar level typically drops while the levels of ammonia and acidity in his or her blood rise. At the same time, the liver may swell and develop fatty deposits. Swelling may also occur in the brain, which can cause seizures, convulsions or loss of consciousness.

The signs and symptoms of Reye's syndrome typically appear about three to five days after the onset of a viral infection, such as the flu (influenza) or chickenpox, or an upper respiratory infection, such as a cold.

Initial signs and symptoms

For children younger than age 2, the first signs of Reye's syndrome may include:

  • Diarrhea
  • Rapid breathing

For older children and teenagers, early signs and symptoms may include:

  • Persistent or continuous vomiting
  • Unusual sleepiness or lethargy

Additional signs and symptoms

As the condition progresses, signs and symptoms may become more serious, including:

  • Irritable, aggressive or irrational behavior
  • Confusion, disorientation or hallucinations
  • Weakness or paralysis in the arms and legs
  • Seizures
  • Excessive lethargy
  • Decreased level of consciousness

These signs and symptoms require emergency treatment.

When to see a doctor

Early diagnosis and treatment of Reye's syndrome can save a child's life. If you suspect that your child has Reye's syndrome, it's important to act quickly.

Seek emergency medical help if your child:

  • Has seizures or convulsions
  • Loses consciousness

Contact your child's doctor if your child experiences the following after a bout with the flu or chickenpox:

  • Vomits repeatedly
  • Becomes unusually sleepy or lethargic
  • Has sudden behavior changes

Causes

The exact cause of Reye's syndrome is unknown, although several factors may play a role in its development. Reye's syndrome seems to be triggered by using aspirin to treat a viral illness or infection — particularly flu (influenza) and chickenpox — in children and teenagers who have an underlying fatty acid oxidation disorder.

Fatty acid oxidation disorders are a group of inherited metabolic disorders in which the body is unable to break down fatty acids because an enzyme is missing or not working properly. A screening test is needed to determine if your child has a fatty acid oxidation disorder.

In some cases, Reye's syndrome may be an underlying metabolic condition that's unmasked by a viral illness. Exposure to certain toxins — such as insecticides, herbicides and paint thinner — also may contribute to Reye's syndrome.

Risk factors

The following factors — usually when they occur together — may increase your child's risk of developing Reye's syndrome:

  • Using aspirin to treat a viral infection, such as flu, chickenpox or an upper respiratory infection
  • Having an underlying fatty acid oxidation disorder

Complications

Most children and teenagers who have Reye's syndrome survive, although varying degrees of permanent brain damage are possible. Without proper diagnosis and treatment, Reye's syndrome can be fatal within a few days.

Prevention

Use caution when giving aspirin to children or teenagers. Though aspirin is approved for use in children older than age 2, children and teenagers recovering from chickenpox or flu-like symptoms should never take aspirin. This includes plain aspirin and medications that contain aspirin.

Some hospitals and medical facilities conduct newborn screenings for fatty acid oxidation disorders to determine which children are at greater risk of developing Reye's syndrome. Children with known fatty acid oxidation disorders should not take aspirin or aspirin-containing products.

Always check the label before you give your child medication, including over-the-counter products and alternative or herbal remedies. Aspirin can show up in some unexpected places, such as Alka-Seltzer.

Sometimes aspirin goes by other names, too, such as:

  • Acetylsalicylic acid
  • Acetylsalicylate
  • Salicylic acid
  • Salicylate

If your child has the flu, chickenpox or another viral illness, use other medications — such as acetaminophen (Tylenol, others), ibuprofen (Advil, Children's Motrin, Motrin IB, others) or naproxen (Aleve) — to reduce high fever or relieve pain.

There's one caveat to the aspirin rule, however. Children and teenagers who have certain chronic diseases, such as Kawasaki disease, may need long-term treatment with drugs that contain aspirin.

If your child needs aspirin therapy, make sure his or her vaccines are current — including two doses of the varicella (chickenpox) vaccine and a yearly flu vaccine. Avoiding these two viral illnesses can help prevent Reye's syndrome.

Aug. 12, 2014
References
  1. Ferri FF. Ferri's Clinical Advisor 2014: 5 Books in 1. Philadelphia, Pa.: Mosby Elsevier; 2014. https://www.clinicalkey.com. Accessed May 25, 2014.
  2. Cherry JD, et al. Feigin and Cherry's Textbook of Pediatric Infectious Diseases. 7th ed. Philadelphia, Pa.: Saunders Elsevier; 2014. https://www.clinicalkey.com. Accessed May 25, 2014.
  3. NINDS Reye's syndrome information page. National Institute of Neurological Disorders and Stroke. http://www.ninds.nih.gov/disorders/reyes_syndrome/reyes_syndrome.htm. Accessed May 25, 2014.
  4. What is Reye's syndrome? National Reye's Syndrome Foundation. http://www.reyessyndrome.org/what.html. Accessed May 25, 2014.
  5. Chiriboga CA. Acute toxic-metabolic encephalopathy in children. http://www.uptodate.com/home. Accessed May 25, 2014.
  6. Reye's syndrome. The Merck Manual for Health Care Professionals. http://www.merckmanuals.com/professional/pediatrics/miscellaneous_disorders_in_infants_and_children/reyes_syndrome.html. Accessed May 26, 2014.
  7. Medications containing aspirin (acetylsalicylate) and aspirin-like products. National Reye's Syndrome Foundation. http://www.reyessyndrome.org/. Accessed May 28, 2014.
  8. Renaud DL (expert opinion). Mayo Clinic, Rochester, Minn. June 2, 2014.