What is Kawasaki Disease (KD)?
Kawasaki Disease is a relatively rare childhood disease which is also known as mucocutaneous lymph node syndrome. It was first identified by Dr Tomisaku Kawasaki in 1967. In Japan, KD is so common that one of Zoe’s doctors told me that she had seen entire wards filled with KD children in hospitals there. In Singapore, KKH sees 1 case of KD a month. At NUH, they see 1 case every 1-2 months.
KD is a form of vasculitis, meaning that it results in inflammation of the body’s blood vessels.
What causes KD?
Its exact cause is still unknown. However, recent research suggests a genetic predisposition which would explain why it is so common in Japan and so rare in western countries.
What are the symptoms of KD?
These are the five classic symptoms:
1. Persistent fever lasting five or more days
2. Redness and swelling on palms and soles
3. Rash on the torso, particularly in the diaper region
4. Red, cracked lips, strawberry tongue, irritated throat
5. Swollen lymph glands
As you can see, some of these symptoms are the same as what you’d get with a normal viral fever. However, there are few other diseases that present with all five. If a child has less than five but more than three symptoms, he is considered to have atypical KD – which is what Zoe had.
KD may also result in redness and induration (hardening) of the area around the child’s BCG scar. This has been documented as a sign of KD but is not considered a classic symptom as far as I’ve read. Zoe’s BCG scar was slightly red and indurated, and it was one of the things that the doctors checked for after going through the first five symptoms.
Is KD contagious?
The current consensus is that it is not.
Why is KD dangerous?
Because KD is a form of vasculitis, it attacks the heart’s major blood vessels, resulting in dilatation of the arteries and in severe cases, the formation of aneurysms which increase the risks of heart attack. This is the reason early diagnosis is vital, so that treatment can be administered to reduce the risks to the heart.
How is KD treated?
The international standard for treatment of KD is to administer intravenous immunoglobulin (IVIG) before Day 10 of the fever. This treatment is extremely expensive, but reduces the risk of heart damage from 25% to 5%. After Day 10, administering IVIG has little benefit to the patient. After discharge, patients are placed on aspirin therapy – again, to protect the heart. After her discharge, Zoe was placed on aspirin therapy for a month only because follow-up echos showed that her arteries were normal.
Can you get KD more than once?
The recurrence rate for KD is low at around 3 per cent.
What impact does KD have on a child’s lifestyle?
If there is minimal impact on the coronary arteries, then there isn’t much to cramp your child’s style.
