Kawasaki Disease

Kawasaki disease is a condition that causes inflammation (swelling and redness) in blood vessels throughout the body. It mainly affects young children, usually under the age of 5. Although it is uncommon, it is important to recognise because, without treatment, the inflammation can affect the arteries that supply the heart.

The illness tends to follow a pattern of symptoms that appear over several days. It is not passed from child to child, and it is not caused by anything a parent did. With prompt treatment, most children make a full recovery.

The main sign of Kawasaki disease is a high temperature that lasts for 5 days or longer and does not come down well with the usual fever medicines. Alongside the fever, children often develop several other features: a blotchy rash, red and bloodshot eyes without discharge, red, dry or cracked lips, a swollen red tongue sometimes described as a 'strawberry' tongue, swollen glands in the neck, and red, swollen or sore hands and feet. In the weeks afterwards, the skin on the fingers and toes may peel.

Not every child has all of these signs, and they may not all appear at once, which can make the illness hard to recognise. Children are often very irritable and clearly unwell. If your child has a fever lasting several days together with some of these features, it is important to have them assessed.

The exact cause of Kawasaki disease is not known. It is thought that an infection or another trigger may set off an unusual response in the immune system in children who are prone to it, but no single cause has been identified.

It is not contagious, so it cannot be caught from another child, and it is not inherited in a simple way. It is more common in young children and in certain population groups, but it can affect any child.

There is no single test that confirms Kawasaki disease. Doctors make the diagnosis based on the pattern of symptoms, particularly the length of the fever and the combination of features such as the rash, red eyes, lip and tongue changes and swollen hands and feet, after ruling out other illnesses that can look similar.

Blood tests, urine tests and other investigations are often done to support the diagnosis and check how the body is affected. An ultrasound scan of the heart, called an echocardiogram, is used to look at the coronary arteries, and this may be repeated over time to monitor the heart.

Kawasaki disease is treated in hospital. The main treatment is an infusion of antibodies into a vein, known as intravenous immunoglobulin (IVIG), which reduces the inflammation. High-dose aspirin is initially given to reduce inflammation, followed by a lower maintenance dose once the fever subsides to prevent blood clots from forming in the coronary arteries. Some children at higher risk may be offered additional medicines such as steroids.

Starting treatment early, ideally within the first 10 days of illness, greatly lowers the chance of damage to the coronary arteries. This is why a fever that lasts 5 days or more with the features of Kawasaki disease should be assessed without delay, rather than waiting to see if it settles on its own.

After treatment, children are usually reviewed by a specialist and may have repeat heart scans to make sure the coronary arteries are healthy. Most children who are treated early have no lasting heart problems.

Children who developed changes in the coronary arteries need closer, longer-term follow-up with a heart specialist, and sometimes ongoing medication. Aspirin in children is only given on medical advice for this condition; parents should never start it on their own.

Because the cause is unknown, there is no known way to prevent Kawasaki disease and no vaccine for it. It cannot be avoided by hygiene measures in the way that contagious infections can.

What makes the biggest difference is recognising it early. Knowing the warning pattern, a high fever lasting 5 days or more with rash, red eyes, lip and tongue changes and swollen hands and feet, helps parents seek care in time for effective treatment.

With prompt treatment, the outlook for most children is good, and the majority recover fully without lasting heart problems. The fever and other symptoms usually settle quickly once treatment is given.

The main long-term concern is the small group of children who develop changes in the coronary arteries, who need ongoing heart monitoring and care. Early diagnosis and treatment are the most important factors in a good outcome.