Kawasaki disease (KD) is a rare childhood illness that can sometimes lead to serious heart issues.
It was recently thrust into the spotlight after a paediatrician was handed a three-month suspension for failing to properly diagnose and treat a one-year-old boy for KD.
In 2013, the boy was admitted to Gleneagles Hospital with high fever and red eyes, among other symptoms. Dr Chia Foong Lin, who saw him several times, diagnosed him as having a viral fever.
The Singapore Medical Council ruled last month that the failure in diagnosis could have prevented treatment and resulted in the boy developing serious heart problems.
Last week, Dr William Yip, a paediatrician who learnt from Dr Tomisaku Kawasaki, the first person to observe the disease, said in a letter to The Straits Times Forum page that it is difficult to confidently diagnose KD in the first week of illness.
"Even echocardiography to check for coronary artery involvement is not a definitive test because 80 per cent of the patients do not have coronary artery issues," wrote Dr Yip, who has been managing patients with KD for the past 40 years.
Professor Quek Swee Chye lists some signs:
•Fever, usually high and which lasts for more than five days. The fever does not go away with the usual fever medicine and may last for two weeks or longer.
•A rash over the trunk and limbs. Many people mistake the "peeling of fingers and toes" to be a symptom. But it typically occurs three to four weeks after the onset of the disease. By then, the child is usually no longer feverish.
•Red eyes (bilateral conjunctivitis). It is not painful and does not cause any discharge.
•Red lips and tongue, and enlarged lymph nodes in the neck.
•Sometimes, there is swelling and redness of the hands and feet.
• The child is usually very irritable and fretful, and may not eat well.
Professor Quek Swee Chye, who heads the National University Hospital's division of paediatric cardiology, told The Straits Times that the spectrum of presentation can be very varied.
The signs and symptoms of the disease may not all be present - known as incomplete KD - but appear as different combinations in different patients, said Prof Quek. And the sequence of when the signs evolve does not follow a pattern.
Prolonged fever is the hallmark of KD, said Prof Quek, but "as fever with rash is very common in children and is much more common than KD, sometimes, the diagnosis of KD is missed."
KD is self-limiting, so it gets better on its own with time, even without treatment. There is no known cause of the illness.
"What is of concern are the complications, especially of the heart," said Prof Quek.
Appropriate treatment using intravenous immunoglobulins and high-dose aspirin helps to reduce the risk of complications.
Treatment should be initiated within 10 days of the illness and can be started as soon as KD is confidently diagnosed, said Prof Quek.
Some doctors would still consider giving medication beyond 10 days if there is evidence of active inflammation, he said.
As not all the "classical" signs are present in a child with KD, an index of suspicion should be kept in mind if the fever runs a protracted course, said Prof Quek. "When in doubt or if there are unusual signs - for example, a rash - it is best to seek professional advice."