Reye syndrome is sudden (acute) brain damage (encephalopathy) and liver function problems of unknown cause. The syndrome has been associated with the use of aspirin to treat chickenpox or the flu in children.

Reye syndrome is most often seen in children from 4 to 12 years old. Most cases associated with chicken pox have been shown to occur in children age 5 to 9, while those associated with the flu (influenzae type B) have occurred in children aged 10 to 14.

Children with Reye syndrome get sick very suddenly. Typically, Reye syndrome follows an upper respiratory infection (URI) or chickenpox by about 1 week. It frequently begins with vomiting, which is persistent over many hours.

The vomiting is rapidly followed by irritable and combative behavior. As the condition gets worse, the child may have problems with their alert (conscious) level). Untreated, seizures and coma may develop, which can quickly lead to death.

Symptoms of Reye syndrome include:

• Recent upper respiratory infection or chickenpox
• Nausea and vomiting
• Mental status changes
• Lethargy
• Confusion
• Combative behavior
• Loss of consciousness or coma may develop
• Seizures
• Unusual placement of arms and legs (decerebrate posture) -- the arms are extended straight and turned toward the body, the legs are held straight, and the toes are pointed downward)

• Weakness in arms or legs
• Muscle function loss or paralysis of the arms or legs
• Double vision
• Speech difficulties
• Hearing loss

The following tests may be used to diagnose Reye syndrome:

• Blood chemistry tests show low blood sugar (glucose) levels
• Liver function tests show higher than normal levels of liver enzymes
• Serum ammonia test may be higher than normal
• Liver biopsy
• Spinal tap
• Head CT or head MRI scan help rule out other causes of mental status changes

Specific treatment measures have not been determined. Intensive monitoring of the pressure within the brain, blood gases, and blood pH is required. Treatments may include:

• Fluids by IV to provide electrolytes and glucose
• Steroids to reduce swelling in the brain
• Breathing support (a breathing machine may be needed during a deep coma)

When this illness was more common, charcoal hemoperfusion was used to filter out blood toxins. This treatment was done with some success.

How well a person does depends on the severity of any coma, as well as other factors. The average death rate for patients with Reye syndrome is about 40%.

However, the outcome for those who survive an acute episode is good.

• Permanent brain damage
• Coma

Go to the emergency room or call the local emergency number (such as 911) immediately if your child has confusion, lethargy, or other mental changes.

Never give a child aspirin unless specifically told to do so by your doctor.

When a child must take aspirin, care must be taken to reduce the child's risk of catching a viral illness such as the flu and chickenpox. Aspirin should be avoided for several weeks after receiving a varicella (chickenpox) vaccine.

Note: Other over-the-counter medications such as Pepto-Bismol and compounds containing oil of wintergreen also contain aspirin-compounds called salicylates. These should not be given to a child who has a cold or fever.

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Ferri FF. Ferri’s Clinical Advisor: Instant Diagnosis and Treatment. 2005 ed. St. Louis, Mo: Mosby; 2005:738.

Noble J. Textbook of Primary Care Medicine. 3rd ed. St. Louis, Mo: Mosby; 2001:46-47.