Definition

     Reye's 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.

Causes

     Reye's syndrome tends to occur in previously healthy children about a week after common viral infections such as influenza or chickenpox. It can also develop after an ordinary upper respiratory infection such as a cold. The precise reason is unknown, but using aspirin to treat a viral illness or infection may trigger the condition in children.

     Reye's syndrome may be a metabolic condition — one without symptoms (asymptomatic) — that's unmasked by viral illnesses. Reye's syndrome occurs most commonly in children between the ages of 4 and 12.

Symptoms

• 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)

     Other symptoms that may be associated with this disorder include:

• Weakness in arms or legs

• Muscle function loss or paralysis of the arms or legs

• Double vision

• Speech difficulties

• Hearing loss

     Reye's syndrome progresses through five stages, explained below:

• Stage I

  • Persistent, heavy vomiting that is not relieved by eating

  • Generalized lethargy

  • General mental symptoms, e.g. confusion

  • Nightmares

• Stage II

  • Stupor caused by minor brain inflammation

  • Hyperventilation

  • Fatty liver (found by biopsy)

  • Hyperactive reflexes

• Stage III

  • Possible coma

  • Possible cerebral edema

  • Rarely, respiratory arrest

  • Also, symptoms above continue

• Stage IV

  • The ever-deepening coma

  • Large pupils with minimal response to light

  • Minimal but still present hepatic dysfunction

• Stage V

  • Very rapid onset after happening of stage IV

  • Death is imminent

  • Deep coma

  • Strong seizures

  • Respiratory failure

  • Flaccidity

  • Extremely high blood ammonia (above 300mg per 100mL of blood)

Screening and Diagnosis

Complications

     While most children who survive Reye's syndrome don't suffer any long-term damage, this disorder can occasionally result in permanent liver damage, irreversible nervous system damage, coma and death.

     Reye's syndrome may include a combination of the following problems:

• High levels of ammonia and acidity and a low level of sugar in the blood (hypoglycemia)

• Fatty deposits in the liver and abnormal liver function tests

• Poor blood clotting and bleeding caused by liver failure

• Swelling of the brain, sometimes with coma and brain death

     Earlier diagnosis and treatment can greatly reduce the chance of death.

Treatment

     Fortunately, most children whom doctors evaluate for possible signs and symptoms of Reye's syndrome don't have the disease. Instead, they may not have fully recovered from a flu-like illness, or they may be dealing with complications of dehydration. Children who receive a diagnosis of Reye's syndrome, however, may require admission to a pediatric intensive care unit. Drug treatments may include:

• Intravenous fluids. These may include glucose to increase low blood sugar; electrolyte solutions containing sodium, potassium and chloride to correct blood chemistry values; and basic solutions to treat acidity.

• Insulin. Small amounts of insulin can increase sugar metabolism.

• Corticosteroids. A corticosteroid medication can reduce brain swelling and inflammation.

• Diuretics. A diuretic, such as mannitol, can increase fluid loss through urination and help reduce brain swelling.

     Your doctor may want to continuously monitor your child's blood pressure using a thin, flexible tube (arterial catheter). An arterial catheter is threaded into an artery and is commonly used to monitor blood gases and acidity, as well as blood pressure.

     If Reye's syndrome reaches an advanced stage, treatment may include the use of a ventilator to help assist a child with breathing.

Prevention

     To reduce the risk of Reye's syndrome, avoid giving aspirin or medications that contain aspirin to your child to treat viral illnesses. Other names for aspirin include:

• Acetylsalicylic acid

• Acetylsalicylate

• Salicylic acid

• Salicylate