Kawasaki disease is an acute inflammatory disease that particularly affects children under the age of 5. Serious cardiac complications are possible: this pathology generally requires hospitalization. Doctissimo takes stock. 


This febrile inflammatory disease is present all over the world, but it has been much more common in Asian populations , and especially in Japan.  Indeed, the prevalence of the disease in children under 5, who are most affected, has been estimated at 8.1 / 100,000 in the UK, 17.1 / 100,000 in the US and to 112/100 000 in Japan.

Kawasaki disease, what is it?

It is a febrile systemic vasculitis linked to immune dysfunction . In the absence of treatment, it is complicated by coronary aneurysms in 25 to 30% of cases. It is the most common cause of acquired heart disease in children in industrialized countries, and may pose a risk for ischemic heart disease in adults.

Early manifestations are acute myocarditis with heart failure , of  arrhythmias , an endocarditis and pericarditis . Of coronary artery aneurysms can then be formed. Extravascular tissue can also become inflamed, including the upper respiratory tract, pancreas, bile ducts, kidneys, mucous membranes, and lymph nodes.

Causes of Kawasaki disease 

The cause of this adeno-cutaneous-mucous syndrome is unknown, although  several avenues have been put forward. The epidemiology and clinical presentation indeed suggest an infection or an abnormal immunological reaction to an infection in a genetically predisposed child. 

There is a predisposing genetic ground , which would explain the frequency of the affection in Asia (Japan).

What are the symptoms ? 

This diagnosis is suggested in a child under 5 years of age with  a high fever which persists for one or two weeks despite antipyretics and antibiotics, with a deterioration of the general condition.

Other symptoms are often associated: 

  • A conjunctivitis bilateral;
  • Pharyngitis with raspberry tongue;
  • Stomatitis;
  • Painful cheilitis (the lips are red and cracked);
  • A rhinitis , a discreet cough;
  • A palmoplantar erythema appears from the 4th day of the disease with edemas of the backs of the hands and feet;
  • Skin rash;
  • Of headaches  ;
  • Desquamation appears around the 2nd or 3rd week of development at the nail-pulp junction of the finger and toe; 
  • Cervical lymph nodes are common; 
  • Joint pain , diarrhea, abdominal pain, nausea, vomiting are possible;
  • Neurological signs are sometimes highlighted: lymphocytic meningitis, encephalitis, intracranial hypertension  ;
  • A slight jaundice reflects liver damage.

The risk is cardiac : myocarditis, pericarditis and damage to the coronary arteries ( myocardial infarction ) dominate the prognosis. The biological assessment shows a non-specific inflammatory syndrome : hyperleukocytosis with polynucleosis, very high sedimentation rate (VS), increased C reactive protein (CRP), increased fibrin, hyper alpha 2 globulinemia, etc. the number of platelets ( thrombocytosis ) and IgE (immunoglobulin E).

Possible complications 

Without complications,  the evolution is favorable in about 3 weeks. It is the cardiac complications which weigh down the prognosis : myocarditis, pericarditis and especially the attack of the coronary arteries which can cause at any time sudden death, cardiac rhythm disturbances , acute heart failure, myocardial infarction etc.

There are aggravating factors which would be:

  • Age less than 1 years;
  • The male sex;
  • Very prolonged fever;
  • Very high sedimentation rate;
  • Elevated thrombocytosis;
  • The significant and prolonged increase in IgE.

1.5% of children die during convalescence from a ruptured coronary aneurysm or myocardial infarction.

Treatment of Kawasaki disease

First of all,  hospitalization is essential. Children should be treated by (or in close collaboration with) an experienced pediatric cardiologist, an infectious disease specialist, or a pediatric rheumatologist. Treatment is based on two pillars of d oses high IV immunoglobulin (IVIG) and aspirin in high doses.