Reye Syndrome

• Reye syndrome is a rare and severe illness that affects children.
• Reye syndrome is associated with viral infection and aspirin use.
• Reye syndrome causes vomiting and mental-status changes.
• Diagnosing Reye syndrome primarily depends on the clinical history of symptoms.
• The most common abnormal laboratory tests with Reye syndrome include elevated liver enzymes, elevated ammonia levels, and low serum glucose levels.
• Treatment is supportive, and even with treatment, severe Reye syndrome results in permanent brain damage and death.
• Since educating parents about the dangers of aspirin use, the incidence of Reye syndrome has decreased markedly.

Reye syndrome is a rare but often severe and even fatal illness that primarily occurs in children and adolescents. Children diagnosed with Reye syndrome generally present with vomiting and mental-status changes. The illness can resolve spontaneously or progress to coma and death. Although the cause is still unclear, studies have identified that there is a relationship between some viral infections and the use of aspirin medications. The CDC recommended educating parents about the dangers of treating children with aspirin in the 1980s, and now the disease occurs very rarely. In 1963, Dr. Ralph Douglas Reye initially described the syndrome.

Although there has been extensive research into the cause of Reye syndrome, medical professionals still do not completely understand it. As mentioned above, the use of aspirin or aspirin-containing medications to treat children with some viral infections, including chickenpox, influenza, and gastroenteritis, is associated with the development of the disease. Ultimately, the causes of symptoms associated with Reye syndrome relate to dysfunction of the liver and a resultant increase in serum ammonia levels and other toxins. These toxins cause increased pressure in the brain and swelling, leading to brain dysfunction and can progress to death.

Most children diagnosed with Reye syndrome have a history of a recent viral infection. Health care providers identify chickenpox and influenza most often, though they have also described rotavirus (a cause of bowel inflammation or gastroenteritis). In addition to the recent viral infection, most have a history of taking aspirin to control fever. Some researchers have suggested that children with undiagnosed metabolic disorders may also be at risk, though this is not completely clear.

The primary symptoms of Reye syndrome include uncontrolled vomiting and mental-status changes. These symptoms are generally the result of increased intracranial pressure and brain swelling. If untreated and progressive, the disease is fatal. Even if physicians identify and treat it early, some patients will still have progressive disease resulting in death or permanent brain damage.

Doctors consider a diagnosis of Reye syndrome in any child who has unexplained brain dysfunction (encephalopathy), vomiting, and liver dysfunction. A history of a recent viral infection and aspirin use certainly supports the diagnosis. In general, laboratory studies that reveal a prominent blood acidosis and an increase in liver enzymes and ammonia levels and marked decreases in serum glucose (hypoglycemia) are supportive of the diagnosis. However, it should be noted that other metabolic disorders can have with similar symptoms. There are reports of undiagnosed metabolic diseases that may be associated with a patient having Reye syndrome-type physical findings and metabolic derangements. Medical professionals describe these patients as having "Reye-like syndrome."

Unfortunately, there is no effective treatment for Reye syndrome. Primarily, the treatment aims to decrease the effects of the metabolic dysfunction. Health care providers admit patients with Reye syndrome to an intensive care unit where doctors who specialize in the care of critically ill children can manage them. In this setting, they can be monitored for a worsening neurologic and metabolic condition. The primary goal is to manage electrolyte imbalances and brain swelling. It is difficult to predict which patients will have a progressive illness, however some recommend using medications aimed at lowering the serum ammonia level (ammonia is one cause of increased brain swelling). In addition, in some cases of progressive and resistant Reye syndrome, physicians have used hemodialysis to remove toxins believed to be partly responsible for the brain swelling.

There is significant variation in outlook amongst children diagnosed with Reye syndrome. It is dependent upon the severity and progression of the disease. Some children may have mild disease and completely recover, and others may develop permanent dysfunction of the brain or die from the disease. In general, children diagnosed and treated early in the course of the illness have better outcomes. Studies also suggest that those presenting with high ammonia levels have a worse prognosis.

Although we do not know how to prevent Reye syndrome, we do know that reducing aspirin use in children has resulted in a decrease in the incidence of the illness. In 1980, there were over 500 cases of Reye syndrome in the United States, and now there are only one to two cases per year. The United Kingdom has seen similar statistics, as well. Health officials attribute this remarkable reduction to the cessation of aspirin use in patients less than 18 years of age. It is important to note that several over-the-counter products contain aspirin or aspirin-like compounds. Pepto-Bismol is such an example. There is a separate product without aspirin-like compounds available.

Most research focuses on understanding what the triggers are for Reye syndrome and how aspirin is involved in the disease. In addition, some are trying to determine why some patients progress rapidly and some cases simply resolve.

National Reye Syndrome Foundation
http://www.reyessyndrome.org