Reye's Syndrome

Reye's syndrome is a very rare but serious disease that most often occurs in children 6 to 12 years old. The exact cause is not known; however, it is associated with children who have recently had chickenpox (varicella) or flu (influenza) and taken aspirin.

Reye's syndrome is an acute, noninflammatory encephalopathy that usually occurs in children and is associated with fatty degeneration of the liver. Case fatality rates range from 26% to 42%, and any delay in recognition, aggressive management, or disposition is strongly associated with a poor outcome.

Causes

Reye's syndrome is most often seen in children from 4 to 12 years old, with a peak incidence at age 6. It is often associated with children who are given aspirin-containing medicines while they have either chickenpox (varicella) or the flu (influenza). It can also develop after an ordinary upper respiratory infection such as a cold. The precise reason is unknown.

Symptoms

• History of a prodromal illness in 75% to 95%, either influenza B or varicella infection ++++ ; followed by severe, repetitive vomiting 3 to 6 days later during apparent convalescence ++++ ; then altered behavior, usually irritability and lethargy
• History of therapeutic dosages of salicylate during the antecedent infection ++++; 75% to 95% sensitivity, limited specificity
• Approximately 75% of cases occur in winter months.
• Between 75% to 80% of cases occur in children 5 to 15 years old, the rest in children under 5. These cases may be more difficult to detect because the differential diagnosis for vomiting and lethargy is large; adult cases are rare but can occur, following the same history, clinical course, and laboratory values as pediatric cases.
• Afebrile by the time of presentation

Signs

• Disease progresses in stages; 70% to 80% present in precomatose stages (I-II).
• Stage I - lethargy only
• Stage II - combative or stuporous; inappropriate verbalizing; sluggish pupillary reaction; conjugate deviation on doll's eyes maneuver; may have nonpurposeful response to pain; seizures
• Stage III - same as stage II except comatose with decorticate posture and response to pain
• Stage IV - same as stage III except decerebrate posture and response to pain, inconsistent or absent oculocephalic reflex
• Stage V - same as stage IV except flaccid with no response to pain, no pupillary response, no oculocephalic reflex
• Tachypnea ++++
• Lack of jaundice or nuchal rigidity ++++
• Hepatomegaly +++
• Dehydration ++
• Arrhythmias and myocarditis can occur rarely in advanced stages.

Treatment

Reye's syndrome is a life-threatening emergency that requires intensive management.

There is no cure for RS but early diagnosis, is primarily aimed at protecting the brain against irreversible damage by reducing brain swelling, reversing the metabolic injury, preventing complications in the lungs, and anticipating cardiac arrest.

Treatment in the early stages includes intravenous sugar to return levels to normal and plasma transfusion to restore normal clotting time. Intracranial pressure is monitored, and if elevated, is treated with intravenous mannitol and hyperventilation to constrict the blood vessels in the brain. If the pressure remains high, barbiturates may be used.

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.