In 1963, North Carolina doctor George Johnson reported an epidemic of 16 fatal cases of an encephalitis-like illness during an influenza B outbreak. It became known as syndrome, named after Australian pathologist R. Douglas Reye, who first reported it as a distinct syndrome in 1963. The syndrome had been reported as early as 1929 but now was identified and characterized as a distinct entity. In the late 1960s, the Centers for Disease Control and Prevention (CDC) developed case criteria that included mental status changes (delirium or coma) and a liver biopsy that showed fat accumulation in the liver (or high levels of liver enzymes and ammonia in the blood).
Reye syndrome is still not well understood. It predominantly affects children between 4 and 16 years of age, and occurs more frequently when viral diseases are epidemic, such as during the winter months or following an outbreak of chickenpox or influenza B.
The use of salicylates like aspirin during viral disease appears to be statistically linked to the incidence of Reye syndrome, even though there is no conclusive proof.
No single diagnostic test to detect Reye syndrome currently is available.
Signs and Symptoms
The signs and symptoms of Reye syndrome are almost always preceded by a viral illness. This could be an upper respiratory tract infection, diarrhea of infectious origin, or chickenpox (Reye syndrome symptoms usually appear 3 to 5 days after the onset of the chickenpox rash). Many cases are mild and may even go undetected; others may be severe, requiring aggressive care.
Symptoms include nausea, vomiting, lethargy, and indifference. The child may exhibit irrational behavior or delirium, and rapid breathing. In the later stages, breathing becomes sluggish and the child becomes comatose, with dilated pupils. The liver may be enlarged, but there is usually no jaundice or fever.
Reye syndrome is rare: approximately 0.1 cases per 100,000 population. It is, however, often thought of when a child has continual vomiting or change of mental status - particularly after a recent viral illness.
Although severity varies, Reye syndrome should be considered an acute disorder that is potentially life threatening.
Prevention
Aspirin and other salicylate drugs should never be used in the treatment of chickenpox, influenza, and other viral diseases. In general, aspirin should not be used for children or teenagers except on the advice of a doctor for certain conditions.
Incubation
Reye syndrome can occur several days (range: 1-14 days) after a viral infection.
Duration
The duration varies with the severity of the disease. Reye syndrome can be mild and self-limiting or, rarely, can progress to death within hours. But the progression may stop at any stage, with complete recovery in 5 to 10 days.
Contagiousness
The viral illnesses that lead to Reye syndrome are contagious; the syndrome itself is noncontagious.
Home Treatment
Children with Reye syndrome are usually treated in a hospital; if seriously ill, in a hospital intensive care unit.
Professional Treatment
Treatment is supportive rather than to "cure" the illness. The clinical care team focuses on making sure a child with Reye syndrome maintains proper fluid and electrolyte balance, nutritional, and cardiorespiratory status. The child stands the best chance of recovery when these systems are as balanced as possible.
Seriously ill children will require intensive monitoring during this syndrome. A variety of catheters (nasogastric tubes, urinary catheters, etc.) may be needed to monitor and control fluids, electrolytes, blood gas status, and nutrition. Patients are not given any food by mouth, only intravenous (IV) nutritional fluids. The fluids are also selected to ensure a proper balance of electrolytes, which enhance cell nutrition and help control water balance outside and inside cell walls.
Mechanical ventilation (a breathing machine or respirator) may be necessary if breathing becomes too sluggish. Intracranial pressure (pressure of the fluid within the central nervous system within the skull) and blood pressure may be monitored. The body may be cooled and drugs like barbiturates given in order to slow metabolism and decrease intracranial pressure. Small quantities of insulin may be given to increase glucose metabolism, corticosteroids to reduce brain swelling, and diuretics to increase fluid loss.
The prognosis for children with Reye syndrome has improved. Earlier diagnosis and better treatment have reduced the mortality rate to about 20% in recent years. The earlier the syndrome is detected, the better the chances for survival. Children who progress to the late stages of the syndrome may have continuing neurological defects.
When to Call Your Child's Doctor
Incidence of Reye syndrome has fallen dramatically since its discovery. If, however, your child shows symptoms of nausea, vomiting, or behavioral changes following a viral illness such as the flu or a cold, contact your child's doctor immediately. Of course, many children with viruses will have some of these symptoms. Most will not have Reye syndrome. Nevertheless, early detection is the key to successful treatment of Reye syndrome.
