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Kawasaki disease
Pathophysiology
Kawasaki disease is a systemic inflammation of the small and medium size blood vessels. The coronary
arteries are most affected, which is why this condition can lead to coronary aneurisms
due to occlusion of the coronary arteries by thrombi
The cause is unknown but may be attributed to infectious process and it is mediated by the immune
system.
Epidemiology
Kawasaki disease is the leading cause for acquired heart disease in children
Patients hospitalized in US with Kawasaki disease are 19 out of 100000 in patients younger than 5 years
Asian children are 2.5 times more likely to develop the condition
African American children are 1.5 times more likely to develop
Approximately 75 to 80 percent of cases in the US are seen in children 5 years or younger
Peak times are from January to March
Risk Factors
Asian or pacific islander specially the Japanese population, children 5 years or younger but can be see in
older children too, and boys are more likely to have Kawasaki disease.
Diagnosis
Classic Kawasaki Disease diagnosis can be made with
Five days of high fever (the first day of fever is considered the first day of illness)
Conjunctival redness (may resolve before presentation) and this will play a big role in incomplete KD
Rash (that is maculopapular, diffuse, and erythematous)
Edema and redness of hands and feet
Cervical lymphadenopathy
Cracked erythematous lips, strawberry tong, erythema of pharynx and mucosa
To make the diagnosis the patient must have five days of high fevers with at least four of the previously
mentioned symptoms. If hands and feet inflammation are present the diagnosis can be made with 4 days
of fever.
Careful history must be obtained since some of the symptoms might have resolved at the time of
,2
examination. This means that the questions must be geared to not only present symptoms but also the
ones that are no longer present. The patient or parent may think that symptoms that have subsided are not
important.
Incomplete Kawasaki Disease can be seen in some patients
, 3
They present with less than four symptoms, but diagnosis can be confirmed with presence of coronary
artery abnormalities. As we saw before the redness in the ayes is a symptom that can disappear before the
patient is seen and it is a good example.
To recap lets discuss Three helpful hints to diagnose KD and to do that I will
provide you with the mnemonic
Warm = Fever for > 5 days
• C = Conjunctivitis without exudate
• R = Rash
• E = Edema or erythema of hands or feet, followed by desquamation
and nail changes
• A = Adenopathy, often unilateral, cervical node > 1.5 cm
• M = Mucosal erythema, fissures or crusting of lips or strawberry tongue
The fever on this condition is discernable because it is not responsive to
antipyretics.
Younger than 5 years old is a hint even when older children can also have
it
Differential diagnosis
Measles which presents with similar symptoms as KD. Examples of similar symptoms include
conjunctivitis, fever, and rash. Children who have not been vaccinated against measles should be
considered for this diagnosis.
Scarlet fever has similar symptoms as well with fever, rash, strawberry tongue, and lymphadenopathy.
The good thing is that there are symptoms that can help differentiate like the transverse groove in the nails
white coating on tongue.
Staphylococcal scalded skin syndrome has similar symptoms to KD like rash and fever but for this
condition the rash is very tender, and it blisters.
Diagnostic testing
echocardiogram to rule out KD in infant younger than 6 months has a prolonged fever of over 7 days or
do not have the complete symptomology. KD will show coronary aneurisms in the acute phase. Coronary
aneurisms develop in 15 to 25 percent of untreated cases and can lead to death
MRI can show smaller lesions in the coronary arteries, but radiation is a concern
Blood test can be done to confirm or rule out diagnosis.
CBC for high white blood cell count, anemia, and inflammation which are supportive of Kawasaki
disease
On Electrocardiogram (prolonged PR interval, decreased QRS voltage, arrythmias, and ST changes can
be seen)
Kawasaki disease
Pathophysiology
Kawasaki disease is a systemic inflammation of the small and medium size blood vessels. The coronary
arteries are most affected, which is why this condition can lead to coronary aneurisms
due to occlusion of the coronary arteries by thrombi
The cause is unknown but may be attributed to infectious process and it is mediated by the immune
system.
Epidemiology
Kawasaki disease is the leading cause for acquired heart disease in children
Patients hospitalized in US with Kawasaki disease are 19 out of 100000 in patients younger than 5 years
Asian children are 2.5 times more likely to develop the condition
African American children are 1.5 times more likely to develop
Approximately 75 to 80 percent of cases in the US are seen in children 5 years or younger
Peak times are from January to March
Risk Factors
Asian or pacific islander specially the Japanese population, children 5 years or younger but can be see in
older children too, and boys are more likely to have Kawasaki disease.
Diagnosis
Classic Kawasaki Disease diagnosis can be made with
Five days of high fever (the first day of fever is considered the first day of illness)
Conjunctival redness (may resolve before presentation) and this will play a big role in incomplete KD
Rash (that is maculopapular, diffuse, and erythematous)
Edema and redness of hands and feet
Cervical lymphadenopathy
Cracked erythematous lips, strawberry tong, erythema of pharynx and mucosa
To make the diagnosis the patient must have five days of high fevers with at least four of the previously
mentioned symptoms. If hands and feet inflammation are present the diagnosis can be made with 4 days
of fever.
Careful history must be obtained since some of the symptoms might have resolved at the time of
,2
examination. This means that the questions must be geared to not only present symptoms but also the
ones that are no longer present. The patient or parent may think that symptoms that have subsided are not
important.
Incomplete Kawasaki Disease can be seen in some patients
, 3
They present with less than four symptoms, but diagnosis can be confirmed with presence of coronary
artery abnormalities. As we saw before the redness in the ayes is a symptom that can disappear before the
patient is seen and it is a good example.
To recap lets discuss Three helpful hints to diagnose KD and to do that I will
provide you with the mnemonic
Warm = Fever for > 5 days
• C = Conjunctivitis without exudate
• R = Rash
• E = Edema or erythema of hands or feet, followed by desquamation
and nail changes
• A = Adenopathy, often unilateral, cervical node > 1.5 cm
• M = Mucosal erythema, fissures or crusting of lips or strawberry tongue
The fever on this condition is discernable because it is not responsive to
antipyretics.
Younger than 5 years old is a hint even when older children can also have
it
Differential diagnosis
Measles which presents with similar symptoms as KD. Examples of similar symptoms include
conjunctivitis, fever, and rash. Children who have not been vaccinated against measles should be
considered for this diagnosis.
Scarlet fever has similar symptoms as well with fever, rash, strawberry tongue, and lymphadenopathy.
The good thing is that there are symptoms that can help differentiate like the transverse groove in the nails
white coating on tongue.
Staphylococcal scalded skin syndrome has similar symptoms to KD like rash and fever but for this
condition the rash is very tender, and it blisters.
Diagnostic testing
echocardiogram to rule out KD in infant younger than 6 months has a prolonged fever of over 7 days or
do not have the complete symptomology. KD will show coronary aneurisms in the acute phase. Coronary
aneurisms develop in 15 to 25 percent of untreated cases and can lead to death
MRI can show smaller lesions in the coronary arteries, but radiation is a concern
Blood test can be done to confirm or rule out diagnosis.
CBC for high white blood cell count, anemia, and inflammation which are supportive of Kawasaki
disease
On Electrocardiogram (prolonged PR interval, decreased QRS voltage, arrythmias, and ST changes can
be seen)
