Kawasaki disease was first described by Dr. Kawasaki in Japan in 1967. It is an inflammatory disease of the small and medium size blood vessels “vasculitis” throughout the body.
- most commonly affects children from 1 to 4 years of age
- can affect younger and older children
- is most common in children of Asian ancestry but has been seen in children of all ethnicities
- affects boys more than girls at a 1.5:1 ratio
What Causes Kawasaki Disease?
The cause remains a medical mystery. There have been many theories over the past 50 years ranging from carpet shampoo to heavy metal toxicity to various infectious agents. The most recent hypotheses revolve around a viral infection triggering an autoimmune process.
Signs & Symptoms of Kawasaki Disease
High fever is the most common sign of Kawasaki Disease. The fever will persist for 7-14 days in most patients. This helps to differentiate Kawasaki disease from common viral illnesses where fever usually is self-limited to 3-5 days.
The vast majority of patients will develop bilateral conjunctivitis “pink eye” and a rash over the chest, abdomen, and back. Cracking and redness can be seen around the lips and inside the mouth. Many patients will also have enlargement of the lymph nodes in the neck and swelling of the hands and feet.
Less common findings are vomiting, diarrhea, and jaundice. Some patients may also experience severe joint pain and swelling.
Common laboratory findings include:
- Elevated serum C-reactive protein
- Elevated serum white blood cell and platelet counts
- White blood cells & protein in the urine
- Elevated liver function tests
Diagnosing Kawasaki Disease
There is no diagnostic test for Kawasaki disease and the diagnosis must be made clinically. The signs and symptoms of Kawasaki disease can be confused with other diseases, and it is important to distinguish it from measles, scarlet fever, allergic reactions, and toxic shock syndrome.
Patients younger than 1 year of age may not exhibit all of the common signs and symptoms, making the diagnosis particularly difficult.
Since prolonged fever is the most consistent finding in these children, parents and physicians should consider Kawasaki disease in any child who has high, persistent fevers beyond 5 days.
Consequences & Treatment of Kawasaki Disease
Coronary artery aneurysms and stenosis are the most important consequences of Kawasaki disease and occur in ~ 25% of untreated patients.
This can lead to ischemic injury to the heart. However, early treatment (within 10 days of onset of fevers) with intravenous immunoglobulin (IVIG) + corticosteroids can lower the aneurysm rate to 1-2%.
Aneurysms typically develop 2-4 weeks after the onset of fever; so close follow-up with echocardiographic examinations of the coronaries is necessary and is typically performed two weeks after the onset of fever and again at 6-8 weeks.
Low dose aspirin is used to prevent blood clots during this time while patients are at risk for developing aneurysms. If there is no evidence of aneurysms at 2 months, then patients can discontinue aspirin and often are discharged from further follow-up.
Patients with aneurysms require close follow-up and aspirin continues. In addition, further imaging with cardiac catheterization or CT scan can be performed to evaluate for coronary stenosis, and stress testing is often used for assessing whether children are at risk for participating in exercise activities.
Further research is needed to determine the cause of Kawasaki disease and to evaluate further anti-inflammatory treatments.
About Blair Robinson, MD
Dr. Blair Robinson is a pediatric cardiologist with WakeMed Physician Practices – Pediatric Cardiology. He has clinical interests in interventional cardiac catheterization, fetal echocardiography, cardiac transplantation, and general pediatric cardiology.
Learn more about Dr. Robinson, and schedule an appointment today.