Kawasaki disease is a relatively uncommon illness that mostly affects children under five years of age. It can also occur in older children, and very rarely in teenagers and adults. It is more common in boys, and in children of North Asian ethnicity, but is seen in all ethnic groups.
There are around 200 to 300 cases diagnosed per year in Australia.
When vessels throughout the body become inflamed, including those of the heart (the coronary arteries), it is known as vasculitis. Kawasaki disease is a collection of symptoms caused by vasculitis. What causes the inflammation in Kawasaki disease remains unknown. It is most likely an abnormal
response by the immune system of some children to a common germ. Kawasaki disease is not contagious to other children.
Signs and symptoms of Kawasaki disease
The disease begins with a high fever (over 39ºC), which continues for at least five days. The fever usually doesn’t respond to paracetamol or ibuprofen.
Most children also develop some or all of the following symptoms, which often appear over a number of days:
- a rash on the trunk, limbs and around the nappy area
- red, shiny or dry, cracked lips
- red lumpy (strawberry-looking) tongue
- red bloodshot eyes, without discharge
- swollen and red hands or feet
- large, swollen glands in the neck
- peeling skin in the nappy area (similar peeling around the fingernails and toenails typically occurs later, after 10–14 days)
- joint pains
- extreme irritability (especially in young children).
Other illnesses can be confused with Kawasaki disease. They may require different treatment.
The most important aspect of Kawasaki disease is that it may cause inflammation of the arteries that supply blood to the heart, which can result in an aneurysm (an abnormal swelling in the wall of an artery) that can cause heart problems in the future. This occurs in about a quarter of
patients if they do not receive treatment.
When to see a doctor
Take your child to the GP if your child has a fever for more than two days, or if they are showing other symptoms of Kawasaki disease.
There is no single test for Kawasaki disease, and diagnosis can be difficult. The diagnosis is made by recognising the symptoms and signs of the disease in a child who has an ongoing fever with no other likely explanation. Blood tests may be helpful, but no single blood test is able to
provide a diagnosis.
Other investigations may be performed to try to determine the likelihood of Kawasaki disease. Your doctor will discuss these with you and might refer your child to be seen by a paediatrician or local emergency department.
Treatment for Kawasaki disease
If your child has Kawasaki disease, they will need to be treated in hospital.
The treatment is intravenous (through a drip into a vein) immunoglobulin, taken from donated blood transfusions. Immunoglobulins (or antibodies) are used by the immune system to fight germs (viruses or bacteria) in the body.
Large doses of intravenous immunoglobulin are effective in stopping the fever and other symptoms of Kawasaki disease in about 80 per cent of cases, and will prevent damage to the coronary arteries (the small blood vessels that supply the heart muscle) in most children.
Up to 10 per cent of children who have Kawasaki disease develop problems with their coronary arteries, and more rarely with their heart valves or heart muscle. An ultrasound of your child's heart (called an echo test) will be performed during their stay in hospital.
Most children with Kawasaki disease are prescribed aspirin, with low doses to be continued for several weeks. Your child will have to stay in hospital for a few days until the illness begins to improve.
Care at home
Once you go home, it may take three or four weeks for your child to fully recover. Don't be alarmed if your child gets some peeling of the skin on their hands or feet – this is very common in the second week of the illness.
If your child is due a routine MMR (measles, mumps, rubella) or varicella (chickenpox) immunisation, this should be delayed until 11 months after the immunoglobulin treatment.
Follow-up
If your child has Kawasaki disease they will need to have long-term follow-up care with their GP and a paediatrician.
They will have another echo test after six to eight weeks. If this second echo is normal, it is unlikely that further changes to the coronary arteries will occur. Aspirin is usually stopped if the six-week echo is normal. If any damage has occurred, your child will be seen by a paediatric
cardiologist (children's heart specialist).
Recurrence of Kawasaki disease is very rare (less than one per cent of cases). It is more common for a child who had previous Kawasaki disease to have peeling of the hands and feet when they become unwell with other infections. This is not usually a recurrence of Kawasaki disease, but it can
worry families. If you are concerned, consult your paediatrician.
The vast majority of children with Kawasaki disease recover fully and live normal lives.
Key points to remember
- Kawasaki disease starts with a high fever that lasts five days or more.
- The features may appear over a number of days and diagnosis can be difficult.
- The disease is treated with intravenous immunoglobulin and aspirin.
- Follow-up is required by your GP and paediatrician.
- Most children with Kawasaki disease recover completely.
For more information
Common questions our doctors are asked
Will my child be more likely to develop heart disease when
they are older after having Kawasaki disease?
No. If no damage was caused with the initial illness, your child is unlikely to
have heart disease as they grow older as a result of Kawasaki disease. They
will not need ongoing testing of their heart.
I thought it was dangerous to give aspirin to children. Is
it safe for my child to take it for several weeks?
Children under 12 should not take aspirin for pain relief,
because it can cause a rare but serious illness called Reyes Syndrome. The
aspirin given to children with Kawasaki disease is in a low dose –
significantly lower than when aspirin is used for pain relief – and is safe to
take when under medical supervision.
Is it risky to be given immunoglobulins from blood
transfusions?
Some families worry about their child being
given blood products. It is important to understand that the risks of
transfusion are very low, yet the risks from untreated Kawasaki disease are
quite high.
Developed by The Royal Children's Hospital General Medicine department. We acknowledge the input of RCH consumers and carers.
Reviewed April 2018.
This information is awaiting routine review. Please always seek the most recent advice from a registered and practising clinician.
Kids Health Info is supported by The Royal Children’s Hospital Foundation. To donate, visit
www.rchfoundation.org.au.