Reye syndrome

Overview

Reye syndrome is a rare but serious condition that causes swelling in the liver and brain. It most commonly affects children and teenagers recovering from a viral infection such as the flu (influenza) or chickenpox (varicella). The syndrome can develop rapidly and is considered a medical emergency, requiring immediate hospitalization and intensive care.

Reye syndrome is strongly associated with the use of aspirin or aspirin-containing medications during viral illnesses in children. Since public health warnings against aspirin use in children, the incidence of Reye syndrome has significantly decreased. Despite its rarity today, it remains a critical diagnosis to consider in children with sudden-onset vomiting, confusion, or altered mental status following a viral illness.

Causes

The exact cause of Reye syndrome is not completely understood, but it appears to be related to mitochondrial dysfunction triggered by viral infection and exposure to certain medications, particularly aspirin.

Key Contributing Factors:

• Use of aspirin: Reye syndrome is most often linked to the use of aspirin or salicylate-containing products during viral infections like influenza or chickenpox in children and teens.

• Viral infections: Especially influenza A and B, varicella (chickenpox), and upper respiratory tract infections.

• Mitochondrial abnormalities: Some children may have underlying genetic or metabolic predispositions affecting mitochondrial function, making them more susceptible.

Risk Factors:

• Age (most common in children ages 4–12)

• Recent viral illness

• Aspirin use during or after a viral infection

• Genetic metabolic disorders (in rare cases)

Symptoms

Symptoms of Reye syndrome typically develop within a few days after a viral illness, particularly if aspirin was administered. The condition progresses in stages and can worsen quickly, so early recognition is crucial.

Early Symptoms:

• Persistent or recurrent vomiting

• Lethargy or unusual sleepiness

• Irritability or behavioral changes

Progressive Neurological Symptoms:

• Confusion or disorientation

• Delirium or hallucinations

• Seizures

• Stupor or coma

• Loss of consciousness

Other Signs:

• Rapid breathing or respiratory distress

• Weakness or paralysis

• Hepatomegaly (enlarged liver) without jaundice

• Elevated liver enzymes and ammonia levels

Diagnosis

Reye syndrome is diagnosed based on clinical presentation, lab tests, and imaging studies. It is essential to differentiate it from other causes of encephalopathy and liver dysfunction, such as infections, poisoning, or metabolic disorders.

Diagnostic Tests:

• Blood tests: Show elevated liver enzymes (AST, ALT), elevated ammonia levels, low blood glucose (hypoglycemia), and prolonged clotting times

• Liver biopsy: May reveal microvesicular fatty changes without inflammation — a hallmark of Reye syndrome

• Lumbar puncture (spinal tap): To exclude meningitis or encephalitis

• CT or MRI scan: To detect cerebral edema (brain swelling)

• Urine and blood screening: To rule out inborn errors of metabolism (especially if there's no history of aspirin use)

Treatment

There is no specific cure for Reye syndrome, but early, aggressive treatment can significantly improve outcomes. Treatment is primarily supportive and aimed at reducing intracranial pressure, stabilizing metabolic balance, and preventing complications.

Hospitalization and Monitoring:

• Admission to an intensive care unit (ICU)

• Continuous monitoring of neurological status, liver function, and blood glucose

Supportive Treatments:

• Intravenous fluids and electrolytes: To correct dehydration and imbalances

• Glucose administration: To treat or prevent hypoglycemia

• Diuretics (e.g., mannitol): To reduce brain swelling and intracranial pressure

• Medications: Such as anticonvulsants for seizures, and medications to reduce ammonia levels (e.g., lactulose)

• Mechanical ventilation: If respiratory failure or coma occurs

Additional Care:

• Management of complications like bleeding, infection, or organ dysfunction

• Family support and psychological counseling for coping with a critical illness

Prognosis

The prognosis of Reye syndrome depends on the severity of brain swelling and how quickly treatment is initiated. Early diagnosis and aggressive management can lead to full recovery, especially in mild to moderate cases.

However, severe cases with prolonged cerebral edema may result in permanent brain damage, learning disabilities, or death. The mortality rate has decreased significantly with improved awareness and early intervention, now estimated at around 20–30% in severe cases.

Prevention remains key, parents and caregivers should avoid giving aspirin or aspirin-containing products to children and adolescents unless specifically instructed by a physician, especially during or after viral illnesses.