What is Reye’s syndrome

Reye’s syndrome is a very rare but serious condition that can potentially affect all organs of the body; with the brain and liver at the greatest risk of damage resulting in swelling in the liver and brain, which can cause seizures, convulsions or loss of consciousness. If Reye’s syndrome is not treated promptly, it may lead to permanent brain injury or death.

Reye’s syndrome most often affects children and teenagers recovering from a viral infection, most commonly influenza or chickenpox. Reye’s syndrome is rare, occurring almost exclusively in children aged less than 18 years. There are estimated to be 0.03-1 cases per 100,000 people aged less than 18 years.

Most cases of Reye’s syndrome occur between 5 and 14 years of age, with males and females being affected with the same frequency. The incidence of Reye’s syndrome has decreased dramatically in recent years, possibly due in part to the decreased use of aspirin in children.

Signs and symptoms of Reye’s syndrome such as confusion, seizures and loss of consciousness require emergency treatment. Early diagnosis and treatment of Reye’s syndrome can save a child’s life.

The symptoms of Reye’s syndrome usually begin 1-3 days after a viral infection, such as a cold, flu or chickenpox.

Initial symptoms can include:

• vomiting repeatedly
• tiredness and lack of interest or enthusiasm
• rapid breathing
• fits (seizures)

As the condition progresses, the symptoms may get more severe and more wide-ranging, and can include:

• irritability, or irrational or aggressive behavior
• severe anxiety and confusion that’s sometimes associated with hallucinations
• coma (loss of consciousness)

Although the cause of Reye’s syndrome is unknown, it typically follows a viral illness such as an upper respiratory tract infection, chicken pox, influenza or gastroenteritis, and is associated with aspirin use during the illness. Any young child who has recently suffered a previous viral infection, such as a flu or chicken pox, should be monitored closely.

Although aspirin is approved for use in children older than age 2, children and teenagers recovering from chickenpox or flu-like symptoms should never take aspirin. Talk to your doctor if you have concerns.

The mortality rate of Reye’s syndrome has fallen from 50% to less than 20% as a result of earlier diagnoses, recognition of milder cases, and more aggressive therapy. Death usually occurs due to swelling of the brain or increased pressure in the brain, but it may also be due to heart failure, respiratory failure, acute renal failure, gastrointestinal bleeding, seizures, or infection.

Reye’s syndrome prognosis

The prognosis for those who survive the acute illness is good. Long term complications include permanent neurological problems as a result of the brain damage occurring during acute illness. The risk of permanent brain damage is not known, but it is thought to be related to the severity of the acute illness. Permanent liver disease has not been reported in survivors.

Reye’s syndrome complications

Most children and teenagers who have Reye’s syndrome survive and some will make a full recovery. However, Reye’s syndrome can leave some people with a degree of permanent brain damage caused by the swelling of their brain. Without proper diagnosis and treatment, Reye’s syndrome can be fatal within a few days.

Long-term difficulties sometimes associated with Reye’s syndrome include:

• poor attention span and memory
• some loss of vision or hearing
• speech and language difficulties
• problems with movement and posture
• difficulty swallowing
• problems with everyday tasks, such as dressing or using the toilet

If your child develops any long-term problems, an individual care plan will be drawn up to address their needs. The plan will be reassessed as they get older.

Reye’s syndrome causes

What causes Reye’s syndrome

The exact cause of Reye’s syndrome is unknown, but it most commonly affects children and young adults recovering from a viral infection – typically, but not exclusively, a cold, flu or chickenpox.

In most cases, Reye’s syndrome seems to be triggered by using aspirin to treat a viral illness or infection — particularly flu (influenza) and chickenpox — in children and teenagers who have an underlying fatty acid oxidation disorder. Fatty acid oxidation disorders are a group of inherited metabolic disorders in which the body is unable to break down fatty acids because an enzyme is missing or not working properly. A screening test is needed to determine if your child has a fatty acid oxidation disorder.

In Reye’s syndrome, it’s thought that tiny structures within the cells called mitochondria become damaged.

Mitochondria provide cells with energy and they’re particularly important for the healthy functioning of the liver.

If the liver loses its energy supply, it begins to fail. This can cause a dangerous build-up of toxic chemicals in the blood, which can damage the entire body and can cause the brain to swell.

In some cases, Reye’s syndrome may be an underlying metabolic condition that’s unmasked by a viral illness. Exposure to certain toxins — such as insecticides, herbicides and paint thinner — also may contribute to Reye’s syndrome.

Risk factors for Reye’s syndrome

The following factors — usually when they occur together — may increase your child’s risk of developing Reye’s syndrome:

• Using aspirin to treat a viral infection, such as flu, chickenpox or an upper respiratory infection
• Having an underlying fatty acid oxidation disorder

Reye’s syndrome prevention

Use caution when giving aspirin to children or teenagers. Though aspirin is approved for use in children older than age 2, children and teenagers recovering from chickenpox or flu-like symptoms should never take aspirin. This includes plain aspirin and medications that contain aspirin.

• Because of the possible link between aspirin and Reye’s syndrome, aspirin should only be given to children under 16 on the advice of a doctor when it’s felt the potential benefits outweigh the risks.

Some hospitals and medical facilities conduct newborn screenings for fatty acid oxidation disorders to determine which children are at greater risk of developing Reye’s syndrome. Children with known fatty acid oxidation disorders should not take aspirin or aspirin-containing products.

• Children under 16 should also not take any products containing aspirin.
• There’s one caveat to the aspirin rule, however. Children and teenagers who have certain chronic diseases, such as Kawasaki disease, may need long-term treatment with drugs that contain aspirin.
• If your child needs aspirin therapy, make sure his or her vaccines are current — including two doses of the varicella (chickenpox) vaccine and a yearly flu vaccine. Avoiding these two viral illnesses can help prevent Reye’s syndrome.

Always check the label before you give your child medication, including over-the-counter products and alternative or herbal remedies. Aspirin can show up in some unexpected places, such as Alka-Seltzer.

Sometimes aspirin goes by other names, too, such as:

• Acetylsalicylic acid
• Acetylsalicylate
• Salicylic acid
• Salicylate
• Salicylate salts

Some mouth ulcer gels and dental gels contain salicylate salts. These shouldn’t be given to children under 16 years of age. There are alternative products that are suitable for under 16s – ask your pharmacist for advice.

If your child has the flu, chickenpox or another viral illness, use other medications — such as acetaminophen (Tylenol, others), ibuprofen (Advil, Children’s Motrin, Motrin IB, others) or naproxen (Aleve) — to reduce high fever or relieve pain.

Reye’s syndrome symptoms

In Reye’s syndrome, a child’s blood sugar level typically drops while the levels of ammonia and acidity in his or her blood rise. At the same time, the liver may swell and develop fatty deposits. Swelling may also occur in the brain, which can cause seizures, convulsions or loss of consciousness.

The signs and symptoms of Reye’s syndrome typically appear about three to five days after the onset of a viral infection, such as the flu (influenza) or chickenpox, or an upper respiratory infection, such as a cold.

Initial signs and symptoms

For children younger than age 2, the first signs of Reye’s syndrome may include:

• Diarrhea
• Rapid breathing

For older children and teenagers, early signs and symptoms may include:

• Persistent or continuous vomiting
• Unusual sleepiness or lethargy

Additional signs and symptoms

As the condition progresses, signs and symptoms may become more serious, including:

• Irritable, aggressive or irrational behavior
• Confusion, disorientation or hallucinations
• Weakness or paralysis in the arms and legs
• Seizures
• Excessive lethargy
• Decreased level of consciousness

These signs and symptoms require emergency treatment.

Reye’s syndrome diagnosis

There’s no specific test for Reye’s syndrome. Instead, screening for Reye’s syndrome usually begins with blood and urine tests as well as testing for fatty acid oxidation disorders and other metabolic disorders.

As Reye’s syndrome is so rare, other conditions that can cause similar symptoms need to be ruled out. These include:

• meningitis – inflammation of the protective membranes surrounding the brain and spinal cord
• encephalitis – inflammation of the brain
• inherited metabolic disorders – conditions, such as medium-chain acyl-CoA dehydrogenase deficiency, that affect the chemical reactions that occur in your body

Blood tests and urine tests can help detect if there’s a build-up of toxins or bacteria in the blood, and they can also be used to check if the liver is functioning normally.

Tests may also be carried out to check for the presence or absence of certain chemicals that could indicate an inherited metabolic disorder.

Sometimes more-invasive diagnostic tests are needed to evaluate other possible causes of liver problems and investigate any neurological abnormalities. For example:

• Spinal tap (lumbar puncture). A spinal tap can help the doctor identify or rule out other diseases with similar signs and symptoms, such as infection of the lining that surrounds the brain and spinal cord (meningitis) or inflammation or infection of the brain (encephalitis). During a spinal tap, a needle is inserted through the lower back into a space below the end of the spinal cord. A small sample of cerebrospinal fluid is removed and sent to a lab for analysis.
• Liver biopsy. A liver biopsy can help the doctor identify or rule out other conditions that may be affecting the liver. During a liver biopsy, a needle is inserted through the skin on the upper right side of the abdomen and into the liver. A small sample of liver tissue is removed and sent to a lab for analysis.
• Computerized tomography (CT) scan or magnetic resonance imaging (MRI). A head CT or MRI scan can help the doctor identify or rule out other causes of behavior changes or decreased alertness. A CT scan uses a sophisticated imaging machine linked to a computer to produce detailed, 2-D images of the brain. An MRI scan uses a strong magnetic field and radio waves rather than X-rays to generate images of the brain.
• Skin biopsy. Testing for fatty acid oxidation disorders or metabolic disorders may require a skin biopsy. During a skin biopsy, a doctor takes a small skin sample (biopsy) for analysis in a lab. A biopsy can usually be done in a doctor’s office using a local anesthetic.

Reye’s syndrome treatment

If Reye’s syndrome is diagnosed, your child will need to be immediately admitted to an intensive care unit (ICU).

Treatment aims to minimize the symptoms and support the body’s vital functions, such as breathing and blood circulation.

It’s also essential to protect the brain against permanent damage that can be caused by the brain swelling.

Medicines may be given directly into a vein (intravenously), such as:

• electrolytes and fluids – to correct the level of salts, minerals and nutrients, such as glucose (sugar), in the blood
• diuretics – medications to help rid the body of excess fluid and reduce swelling in the brain
• ammonia detoxicants – medications to reduce the level of ammonia
• anticonvulsants – medications to control seizures

A ventilator (breathing machine) may be used if your child needs help with breathing.

Vital body functions will also be monitored, including the heart rate and pulse, the air flow to their lungs, blood pressure and body temperature.

Once the swelling in the brain has reduced, the other functions of the body should return to normal within a few days, although it may be several weeks before your child is well enough to leave hospital.