Reye’s Syndrome

Reye’s syndrome is a rare childhood condition that makes your brain swell. It happens when your liver can’t filter ammonia out of your blood. It’s most common among children who take aspirin for a viral infection or illness. The condition usually develops within a week after the onset of a viral illness but can happen anywhere between 12 hours and three weeks after one.

Today, in the U.S., there are only a handful of Reye’s syndrome cases each year. But it’s still a serious condition. Experts estimate that it’s fatal in up to 2 out of 5 cases.

Reye’s syndrome symptoms

Reye’s syndrome symptoms happen in five stages.

Stage 1 symptoms:

• Severe, repeated vomiting
• Lethargy or being sleepier than usual
• Confusion
• Nightmares

Stage 2 symptoms:

• Disorientation, delirium or combativeness
• Stronger-than-usual reflexes (hyperreflexia) and showing the Babinski reflex
• Dilated pupils
• Hyperventilation
• Fast heartbeat (tachycardia)

Stage 3 symptoms:

• Coma
• Decorticate posture (a pose your body takes on due to brain injury)

Stage 4 symptoms:

• Deeper coma with decerebrate posturing
• Wide pupils with minimal or no response to light

Stage 5 symptoms:

• Seizures
• Paralysis and no deep tendon reflexes
• No pupil reaction
• Respiratory arrest
• Death

Reye’s syndrome causes

Experts don’t fully understand how or why Reye’s syndrome happens. Research previously linked it to children taking aspirin because of viral infections, like the flu or chickenpox. But newer research suggests that aspirin and viral illnesses might not be the only factors.

Another key factor could be undiagnosed inborn errors of metabolism (IEM) that affect mitochondria in your liver cells. Mitochondria are the powerhouses of your cells, like engines that burn fuel to work. But having an IEM can make it harder for liver cells to process a drug like aspirin. That, plus the added strain of a viral illness, might cause your liver to stop working properly.

One of your liver’s key jobs is to filter ammonia out of your blood. If it builds up in your blood, that’s called hyperammonemia. Disruptions in your liver can make it harder for your blood to clot, too.

Ammonia is extremely toxic to your brain, causing hepatic encephalopathy. That makes your brain swell (cerebral edema). But there isn’t a lot of extra room inside your skull, so the pressure from the swelling damages your brain.

How doctors diagnose Reye’s syndrome

Healthcare providers can diagnose Reye’s syndrome using a combination of methods. They’ll start by asking you about your child’s recent illnesses or symptoms. They’ll also do physical and neurological exams.

Lab tests are also an essential part of diagnosing Reye’s syndrome. The likely tests include:

• Blood tests to check ammonia levels or prothrombin time (clotting time)
• Brain imaging CT scan or MRI
• Spinal tap (lumbar puncture) to rule out other conditions
• Liver biopsy (to check for liver damage)

How is Reye’s syndrome treated?

There’s no direct treatment for Reye’s syndrome. Healthcare providers will try to manage the effects and symptoms so they don’t cause serious or permanent damage. Some treatments they’ll use include:

• Intubation and mechanical ventilation: These ensure you keep getting oxygen even when you can’t breathe on your own.
• Medications: There are many medications that might help Reye’s syndrome. Some lower ammonia levels in your blood. Others treat or prevent symptoms like seizures, or reverse decreases in your blood’s clotting ability.
• Intravenous (IV) fluids: These keep you hydrated. They can also include glucose to keep your blood sugar steady.
• Dialysis: If ammonia levels in your blood are dangerously high, dialysis can help lower them quickly.
• Managing pressure inside your head: Providers may keep your head elevated. They can also use medications or other means to minimize or prevent brain swelling.

Recovery time

The recovery time for Reye’s syndrome can take days or weeks. It varies depending on many factors. Your child’s healthcare provider is the best one to ask for more information. They can tailor the information to the specifics of your child’s case.

What can I expect if my child has Reye’s syndrome?

The outlook for Reye’s syndrome is best with early diagnosis and treatment. If your child is given or takes aspirin, call their pediatrician right away. And if your child has taken aspirin and starts showing the early symptoms of Reye’s syndrome, they need immediate care. Call 911 (or your local emergency services number) or take them to the nearest hospital right away.

Reye’s syndrome can cause complications, especially when it’s severe. Some of these can be long-term or permanent effects. The possible complications include:

• Aspiration pneumonia
• Brain damage
• Diabetes insipidus
• Digestive tract bleeding
• Epilepsy
• Intellectual disability
• Kidney failure
• Muscle weakness
• Nerve damage
• Sepsis

Can Reye’s syndrome be prevented?

Yes, Reye’s syndrome is preventable. The most effective way to prevent it is to not give children aspirin unless their pediatrician or healthcare provider recommends it.

One key thing to know is that many over-the-counter medications include aspirin as an ingredient. That means it’s critical that you read medication labels.

If you have questions about what to give your child, ask their pediatrician. They can recommend products that are effective and safe for your child to take.

Some conditions, like Kawasaki disease, still have aspirin as a key part of their treatment. If your child has Kawasaki disease, their pediatrician will take extra steps to catch and treat Reye’s syndrome early.