disease was described in 1967 by a Japanese paediatrician called
Tomisaku Kawasaki. He recognized a group of children with fever,
skin rash, conjunctivitis, enanthem (redness of the throat and
oral mucosa), swelling of the hands and feet and enlarged lymph
nodes (filters that kill bacteria and viruses) in the neck,
initially called mucocutaneous lymph node syndrome. A few years
later, heart complications, like aneurysms of the coronary arteries
(large dilatation of blood vessels) were reported.
Kawasaki disease is an acute systemic vasculitis, meaning there
is inflammation of the walls of blood vessels, that can lead
to aneurysms, mainly of the coronary arteries (the vessels that
supply blood to the heart). Not all children with this disease
will develop aneurysms and the majority will have acute symptoms
common is it?
Kawasaki disease is a rare disease, but one of the most common
vasculitis in childhood, along with Henoch-Schonlein purpura.
It is almost exclusively an illness of young children. About
80 of 100 patients are under the age of five. It is slightly
more common in boys than girls. Although cases of Kawasaki disease
can be diagnosed any time during the year, some seasonal variations
can occur with an increased number in late winter and spring.
It is much more common among Japanese children, but cases are
described all over the world.
are the causes of the disease?
The cause of Kawasaki disease remains unclear, however, an infectious
origin is suspected. Hypersensitivity or a disordered immune
response, probably triggered by an infectious agent (certain
viruses or bacteria), might turn on an inflammatory process
leading to damage of the blood vessels in certain genetically
it inherited? Why has my child got this disease? Can it be prevented?
Is it contagious?
Kawasaki disease is not a hereditary disease, however, a genetic
predisposition is suspected. It is very rare to have more than
one member of a family with this disease. It is not contagious
and cannot be prevented. It’s possible, but very rare,
to have a second episode of this disease.
are the main symptoms?
The illness begins with unexplained high fever of at least five
days. The child is usually very irritable. The fever can be
accompanied, or followed, by conjunctival infection (redness
of the eye), without pus, or secretions.
The child can present different types of skin rash, like measles,
scarlet fever, urticaria (hives), or papules. The skin rash
mainly involves the trunk the extremities and the diaper area.
Mouth changes might include bright red, cracked lips, red tongue,
commonly called strawberry tongue and pharyngeal redness.
Hands and feet can also be involved, with swelling and redness
of palms and soles. These features are followed (around the
second or third week) by a characteristic peeling around the
tip of fingers and toes.
More than half the patients will present enlargement of lymph
nodes in the neck, it is often just one lymph node of 1.5 cm.
Sometimes, other symptoms, such as joint pain, swollen joints,
abdominal pain, diarrhea, irritability and headaches can be
The heart involvement is the most serious manifestation of Kawasaki
disease, due to the possibility of long-term complications.
Heart murmurs, arrhythmias and ultrasound abnormalities can
be detected. The different layers of the heart can show some
grade of inflammation, meaning that pericarditis (inflammation
of the sheet surrounding the heart), myocarditis (inflammation
of the cardiac muscle) and valve involvement can occur. However,
the main coronary feature of this disease is the development
of coronary aneurysms.
the disease the same in every child?
The severity of the disease varies from child to child. Not
every patient has every clinical manifestation and most of the
patients will not develop heart involvement. Aneurysms are seen
in only two of 100 children treated for Kawasaki disease.
Some very young children (under one year of age) often show
incomplete forms of the disease, meaning that they do not present
all the characteristic clinical manifestations, making the diagnosis
more difficult. Some of these young children may develop aneurysms.
the disease in children different from the disease in adults?
This is a disease of childhood, similar forms of this vasculitis
can be present in adults but with a different clinical picture.
is it diagnosed?
A definite diagnosis can be made if unexplained high fever lasts
for five or more days plus four of the five following features
are present: bilateral conjunctivitis, enlarged lymph nodes,
skin rash, mouth and tongue involvement and extremities changes.
If a definite diagnosis is not possible, an incomplete form
of this disease should be considered.
is the importance of tests?
Laboratory findings are not specific for this disease, but reflect
the degree of inflammation. Tests include, elevated ESR (usually
higher than in other similar illnesses), leukocytosis (increased
number of white blood cells), anemia (low count of red blood
cells). The numbers of platelets (cells involved in blood clotting)
is generally normal in the first weeks of the disease, but begin
to rise in the second week, reaching very high counts.
Patients should undergo periodic examinations and assessment
of blood tests until they return to normal.
The electrocardiogram (EKG) and echocardiogram should be obtained
initially. The echocardiogram can detect aneurysms by evaluating
the shape and size of the coronary arteries. In the case of
a child with coronary abnormalities, additional studies and
evaluations will be needed.
it be treated or cured?
The majority of children with Kawasaki disease can be cured,
however, some patients develop heart complications despite the
use of proper treatment. The disease cannot be prevented, but
the best way to decrease coronary complications is to make an
early diagnosis and to start treatment promptly.
are the treatments?
A child with definite or suspected Kawasaki disease should be
admitted to the hospital for observation and monitoring for
possible heart involvement.
To diminish heart complications, treatment should be started
as soon as the diagnosis is made.
Treatment consists of aspirin and intravenous gammaglobulin,
both at high doses. Both treatments will diminish the systemic
inflammation, reducing acute symptoms. High dose gammaglobulin
are an essential part of treatment as they prevent the occurrence
of coronary abnormalities in a high proportion of patients.
Corticosteroids may also be prescribed, but less frequently.
are the side effects of drug therapy?
Gammaglobulin therapy is usually well tolerated. Aspirin treatment
can cause gastric intolerance, as well as temporary elevation
of liver enzymes.
long should treatment last for?
The high dose gammaglobulin is given once in the great majority
of the patients, but sometimes a second dose may be needed.
A high dose aspirin should be given initially, as long as the
fever persists, and then tapered down. The low dose of aspirin
is maintained due to its anticoagulant effect on the platelets,
this means that the platelets will not stick together and helps
to prevent the formation of thrombi (blood clots) inside the
aneurysms. Thrombi formation inside the aneurism may lead to
cardiac infarction, the most dangerous complication of Kawasaki
A child without coronary abnormalities will receive aspirin
for a few weeks, but children with aneurysms should be given
it for longer periods.
about unconventional or complementary therapies?
There is no place for unconventional treatments for this disease.
kind of periodic check-ups are necessary?
Kawasaki disease patients should have periodic assessments of
blood counts and ESR until they return to normal.
Sequential echocardiograms are needed to assess the presence
of coronary aneurisms and to follow their course. The frequency
by which they should be performed depends on the presence and
size of the aneurysm. Most of the aneurysms should resolve.
A pediatric rheumatologist should follow the recovery of these
children. In places where a pediatric rheumatologist is not
available, the pediatrician, along with the cardiologist, will
have to monitor these patients, especially the ones who have
had heart involvement.
long will the disease last for?
Kawasaki disease is an illness with three phases. 1) Acute,
which includes the first two weeks when the fever and the other
symptoms are present. 2) Subacute, from the second to the fourth
week, a period in which the platelet count begins to rise and
aneurysms can appear. 3) The recovery phase, from the first
to the third month, when all laboratory tests return to normal
and some of the blood vessel abnormalities (coronary artery
aneurysms) are resolved or diminished in size.
is the long-term prognosis (predicted course and outcome) of
For the majority of the patients, the prognosis is excellent,
as they will develop a normal life, with normal growth and development.
The prognosis for patients with persistent coronary artery abnormalities
depends mainly on the development of stenosis and occlusions
(the reduction of the size of the blood vessel due to the formation
of blood clots).
recommendations for every day life. What about sports? Can the
child be vaccinated?
It is recommended not to vaccinate these patients for at least
three to six months, as the disease and gammaglobulin treatment
affect the immune system and this can last for six months.
Children who did not develop heart involvement will not have
any restriction in practising sports or any other daily activity.
However, children with coronary aneurysms should consult a paediatric
cardiologist regarding participation in competitive activities