- Reye syndrome is a rare cause of encephalopathy (brain disease) and death in children
- There is a correlation between the incidence of Reye syndrome and children suffering from a viral illness, especially influenza or chicken pox, who are given aspirin to reduce their fever.
- For this reason, aspirin is not recommended for routine use in children.
- Most cases occur between the ages of 4 and 12 years
- About the sixth day of the viral illness, the child suddenly develops intractable vomiting rapidly associated with an altered state of consciousness, ranging from lethargy to coma and death.
- There is concomitant liver involvement and dysfunction that ranges from mild to severe.
- The cause is unknown.
- There is no specific treatment.
- The outcome depends on how soon supportive management is started as well as the severity of the disease.
- Most cases are mild and the child recovers completely.
What is Reye syndrome?
Reye syndrome is a disease complex consisting of an acute encephalopathy and fatty degeneration of the liver with associated hypoglycaemia. Dr R. Reye, an Australian pathologist, first described the syndrome in 1963.
What causes Reye syndrome?
The cause is unknown, but a correlation between the incidence of Reye syndrome and children suffering from a viral upper respiratory tract infection, especially influenza (or chicken pox) who were given aspirin to reduce their fever has been reported.
The syndrome reached a peak in the 1970’s but is now rarely diagnosed. The reason for this is unknown.
In recent years, better laboratory techniques and facilities have resulted in the identification and diagnosis of a number of Reye-like syndromes. These are usually caused by rare inherited metabolic defects and occur in young children.
Who gets Reye syndrome and who is at risk?
Children between the ages of 4 and 12 years who are suffering from a viral illness, especially influenza or chicken pox, are at greatest risk.
The situation may be compounded by the use of aspirin in these children.
What are the symptoms and signs of Reye syndrome?
The typical presentation is a previously well child who appears to be recovering from an upper respiratory tract infection and then suddenly on about the 4th to 6th day of the illness develops severe and protracted vomiting along with an altered level of consciousness.
In most cases the child will just be lethargic and irritable, but in some there may be a rapid deterioration with seizures and finally coma. This is due to inflammation and swelling of the brain (cerebral oedema) which is the main cause of death.
The liver becomes enlarged and there will be variable manifestations of liver dysfunction from (most cases) mild to (a few cases) complete liver failure. Hypoglycaemia (low blood glucose) is a severe complication as is a tendency to bleed easily.
How is Reye syndrome diagnosed?
Reye syndrome is a medical emergency and should be suspected in any child showing acute onset of severe vomiting and altered mental status.
Diagnosis is based on the clinical picture and laboratory tests showing abnormal liver function, and confirmed by liver biopsy showing fatty degeneration.
How is Reye syndrome treated?
There is no specific treatment.
Successful supportive management depends on making the correct diagnosis and excluding the Reye-like syndromes; the severity of the illness; reducing the brain swelling and countering the effects of the liver failure.
All children are admitted and given intravenous glucose and fluids. Further management will depend on the severity of the disease. This could be from simple observation and monitoring to giving drugs to reduce the brain swelling; the prevention of seizures or even assisted ventilation. Blood and blood products may be necessary to treat a bleeding tendency.
What is the outcome of Reye syndrome?
The outcome depends on how quickly the diagnosis is made and management started and the severity and duration of the encephalopathy. Mild cases will recover quickly with no neurological deficit, whereas the more severe cases take longer to recover and may have significant neurological deficit.
Death is rare and is due to brain death from the cerebral oedema.
When to see your doctor
A child with a viral upper respiratory tract infection particularly influenza (or chicken pox) who suddenly develops severe vomiting associated with changes in behaviour or decreasing consciousness, and who has been given aspirin, should be seen by a doctor.
Reviewed by Dr John D. Burgess, FCPaed (CMSA), Senior Specialist, Red Cross Children's Hospital.