142: Kawasaki Disease

Question 1

What is Kawasaki disease (KD) and its suspected etiology?

Answer 1

Kawasaki disease (KD) is a multisystem inflammatory process of unknown but suspected infectious etiology.

Question 2

What is the highest incidence of Kawasaki disease in children?

Answer 2

The highest incidence of Kawasaki disease is in Asian children, with 1 in 80 Japanese children developing KD by age 5 years.

Question 3

What are the major symptoms of Kawasaki disease?

Answer 3

Major symptoms of Kawasaki disease include prolonged high fever, conjunctival injection, oral mucosal changes (such as red lips and pharynx and strawberry tongue), redness and swelling of the hands and feet, erythematous polymorphic rash, and cervical lymphadenopathy.

Question 4

What are the potential complications of inflammation in the coronary arteries due to Kawasaki disease?

Answer 4

Inflammation in the coronary arteries can lead to aneurysms, myocardial infarction, aneurysm rupture, and sudden death.

Question 5

How does treatment with intravenous immunoglobulin (IVIG) and aspirin affect coronary artery abnormalities in Kawasaki disease?

Answer 5

Treatment with intravenous immunoglobulin (IVIG) and aspirin, when given in the first 10 days of fever, reduces the prevalence of coronary artery abnormalities from 25% in those treated with aspirin alone to 5% in those who receive IVIG with aspirin.

Question 6

What is the peak age of illness for Kawasaki disease?

Answer 6

The peak age of illness for Kawasaki disease is 9 to 11 months of age.

Question 7

What is the gender ratio of Kawasaki disease incidence?

Answer 7

Kawasaki disease occurs more frequently in boys than girls, with a ratio of 3:2.

Question 8

What are the three forms of cutaneous findings associated with Kawasaki disease?

Answer 8

The three forms of cutaneous findings associated with Kawasaki disease are morbiliform, targetoid, and scarlatiniform (diffuse erythema).

Question 9

What is the risk of Kawasaki disease in siblings compared to the general population?

Answer 9

The risk of Kawasaki disease in siblings is 10-fold higher than in the general population.

Question 10

What is the significance of the infectious agent in the etiology of Kawasaki disease?

Answer 10

Clinical and epidemiologic data support an infectious cause for Kawasaki disease, although the exact etiology is unknown.

Question 11

What is Kawasaki disease (KD) and its primary characteristics?

Answer 11

Kawasaki disease (KD) is a multisystem inflammatory process of unknown but suspected infectious etiology. It primarily affects medium-sized muscular arteries, especially the coronary arteries. Major symptoms include prolonged high fever, conjunctival injection, oral mucosal changes (such as red lips and strawberry tongue), erythematous polymorphic rash, and cervical lymphadenopathy. Treatment with intravenous immunoglobulin (IVIG) and aspirin reduces the prevalence of coronary artery abnormalities significantly.

Question 12

What are the common cutaneous findings associated with Kawasaki disease?

Answer 12

The common cutaneous findings in Kawasaki disease include a generalized exanthem that can take one of three forms: morbiliform, targetoid, and scarlatiniform (diffuse erythema). These findings are pronounced on the trunk and extremities, and may present as erythematous morbilliform exanthem, targetoid or urticarial changes, and diffuse erythema.

Question 13

What is the epidemiology of Kawasaki disease in children?

Answer 13

Kawasaki disease predominantly occurs in children, with 80% of cases in those aged 6 months to 5 years. It can also occur in older children and teenagers, often with a delayed diagnosis. The male-to-female ratio is 3:2, and the incidence is 10-fold higher in Japanese children compared to white children. The peak age of illness is between 9 to 11 months, and the risk in siblings is 10-fold higher than in the general population. Children born to parents who had KD have a risk that is twice as high as the general population, suggesting an infectious agent may be involved.

Question 14

What is the most common cause of acquired heart disease in children in developed nations?

Answer 14

Kawasaki disease (KD).

Question 15

What treatment reduces the prevalence of coronary artery abnormalities in Kawasaki disease?

Answer 15

Intravenous immunoglobulin (IVIG) and aspirin, when given in the first 10 days of fever.

Question 16

What are the long-term complications associated with Kawasaki disease?

Answer 16

Thrombosis and stenosis of the major coronary arteries with myocardial ischemia.

Question 17

What age group is most affected by Kawasaki disease?

Answer 17

Children ages 6 months to 5 years.

Question 18

What is the male to female ratio for Kawasaki disease incidence?

Answer 18

Boys to girls ratio is 3:2.

Question 19

What suggests an infectious agent as the cause of Kawasaki disease?

Answer 19

Higher incidence in children born to parents who had KD, which is twice as high as in the general population.

Question 20

What additional symptoms would confirm a diagnosis of Kawasaki Disease (KD) in a 9-month-old child with a high fever?

Answer 20

To confirm KD, the child must exhibit at least 4 of the 5 clinical features: oral mucosal changes (e.g., red lips, strawberry tongue), changes in the hands and feet (e.g., erythema, swelling), cervical lymphadenopathy, and prolonged fever without other explanation.

Question 21

What is the likelihood of developing coronary artery abnormalities in a 3-year-old child with KD treated with aspirin alone compared to treatment with IVIG and aspirin?

Answer 21

The prevalence of coronary artery abnormalities is 25% in children treated with aspirin alone, compared to 5% in those treated with IVIG and aspirin.

Question 22

What is the significance of a prolonged high spiking fever lasting 10 days in a child with KD?

Answer 22

A prolonged high spiking fever is a hallmark symptom of KD and is required for diagnosis.

Question 23

What are the other forms of rash that may be observed in KD?

Answer 23

Other forms of rash in KD include targetoid and scarlatiniform (diffuse erythema).

Question 24

How does a family history of Kawasaki disease affect a child’s risk?

Answer 24

The risk of KD is 10-fold higher in siblings and twice as high in children born to parents who had KD.

Question 25

What other symptoms are required for a clinical diagnosis of KD in a child with prolonged fever and cervical lymphadenopathy?

Answer 25

For a clinical diagnosis of KD, the child must have at least 4 of the 5 clinical features: conjunctival injection, oral mucosal changes, changes in the hands and feet, rash, and prolonged fever.

Question 26

What are the three forms the polymorphic rash in KD can take?

Answer 26

The polymorphic rash in KD can take the form of morbiliform, targetoid, or scarlatiniform (diffuse erythema).

Question 27

What additional findings would support a diagnosis of KD in a child with prolonged fever and oral mucosal changes?

Answer 27

Additional findings supporting a diagnosis of KD include conjunctival injection, changes in the hands and feet, rash, and cervical lymphadenopathy.

Question 28

What is the long-term risk associated with coronary artery dilation in a child with KD?

Answer 28

The long-term risk associated with coronary artery dilation includes thrombosis, stenosis, and myocardial ischemia.

Question 29

What are the major symptoms of Kawasaki Disease (KD) that can lead to serious complications such as myocardial infarction?

Answer 29

The major symptoms of Kawasaki Disease include: 1. Prolonged high fever 2. Conjunctival injection 3. Oral mucosal changes (red lips, strawberry tongue) 4. Redness and swelling of the hands and feet 5. Erythematous polymorphic rash 6. Cervical lymphadenopathy. These symptoms can lead to inflammation in the coronary arteries, resulting in aneurysms, myocardial infarction, aneurysm rupture, and sudden death.

Question 30

How does the incidence of Kawasaki Disease (KD) differ between genders and ethnicities?

Answer 30

Kawasaki Disease shows a higher incidence in: - Boys compared to Girls at a ratio of 3:2. - Japanese children have a 10-fold higher incidence than white children. This suggests that clinicians should be particularly vigilant in diagnosing KD in young boys and children of Asian descent, especially those aged 6 months to 5 years, as they represent the majority of cases.

Question 31

What is the significance of early treatment with intravenous immunoglobulin (IVIG) and aspirin in Kawasaki Disease?

Answer 31

Early treatment with intravenous immunoglobulin (IVIG) and aspirin within the first 10 days of fever is significant because it: - Reduces the prevalence of coronary artery abnormalities from 25% (with aspirin alone) to 5% (with IVIG and aspirin). - Helps prevent long-term complications such as thrombosis and stenosis of the major coronary arteries, which can lead to myocardial ischemia.

Question 32

What are the three forms of generalized exanthem associated with Kawasaki Disease?

Answer 32

The three forms of generalized exanthem associated with Kawasaki Disease are: 1. Morbiliform 2. Targetoid 3. Scarlatiniform (diffuse erythema). These cutaneous findings are pronounced on the trunk and extremities and are important for clinical diagnosis.

Question 33

What is the age range most affected by Kawasaki Disease, and what are the implications for early diagnosis?

Answer 33

Kawasaki Disease predominantly affects children aged 6 months to 5 years, with: - 80% of cases occurring in this age group. - A peak age of illness between 9 to 11 months. This age range highlights the importance of early diagnosis in young children, as older children and teenagers may experience delayed diagnosis and potentially more severe disease.

Question 34

What are the classic cutaneous findings associated with Kawasaki Disease (KD)?

Answer 34

• Classic periungual desquamation of the fingers and toes - Transverse lines across the fingernails (Beau lines) - Erythema and swelling at the site of bacille Calmette-Guérin vaccine administration - Rash may be pruritic - Groin erythema and desquamation

Question 35

What are the non-cutaneous findings in Kawasaki Disease (KD)?

Answer 35

• Prolonged fever without other explanation - Conjunctival injection - Oral mucosal changes - Changes of the hands and feet - Cervical adenopathy - Extreme irritability is common - Fever is daily, high spiking, intermittent, lasting for 1 to 2 weeks

Question 36

What are the three stages of Kawasaki Disease (KD)?

Answer 36

1. Acute febrile phase 2. Subacute phase – fever resolves 3. Convalescent phase – clinical features normalize, 6-8 weeks after the onset of fever

Question 37

What oral findings are characteristic of Kawasaki Disease (KD)?

Answer 37

• Red, swollen, dry, cracked lips that may bleed - ‘Strawberry’ tongue - Erythema of the mouth and throat

Question 38

What are the common symptoms of Kawasaki Disease (KD) related to the eyes?

Answer 38

• Conjunctival injection with limbal sparing - Conjunctival injection and red dry lips - Photophobia

Question 39

What musculoskeletal symptoms can occur during Kawasaki Disease (KD)?

Answer 39

• Arthritis during the acute febrile phase and subacute phase - Hands and feet can be edematous and painful

Question 40

What are the key clinical features of Kawasaki Disease (KD) that may be observed?

Answer 40

Key clinical features of Kawasaki Disease include: - Conjunctival injection - Oral mucosal changes - Changes of the hands and feet - Rash - Cervical adenopathy - Extreme irritability - Erythema and edema of the hands - Photophobia - Palmar and plantar erythema - Oral findings such as: Red, swollen, dry, cracked lips that may bleed, ‘Strawberry’ tongue, Erythema of the mouth and throat.

Question 41

What are the key clinical features that may indicate Kawasaki Disease (KD) in a patient presenting with prolonged fever and irritability?

Answer 41

Key clinical features of Kawasaki Disease include:

1. Conjunctival injection
2. Oral mucosal changes (e.g., red, swollen, dry, cracked lips; ‘strawberry’ tongue)
3. Changes of the hands and feet (e.g., erythema, edema)
4. Rash (may be pruritic)
5. Cervical adenopathy

These features may not all be present simultaneously, and extreme irritability is common in KD.

Question 42

What are the stages of fever in Kawasaki Disease (KD)?

Answer 42

The stages of fever in Kawasaki Disease are:

1. Acute febrile phase
2. Subacute phase – fever resolves
3. Convalescent phase – clinical features normalize, typically 6-8 weeks after the onset of fever.

Question 43

Why is a skin biopsy not useful for diagnosing Kawasaki Disease (KD)?

Answer 43

A skin biopsy is not useful for diagnosing Kawasaki Disease because the pathologic findings are nonspecific and do not provide definitive evidence for the disease.

Question 44

What are some noncutaneous findings associated with Kawasaki Disease (KD)?

Answer 44

Noncutaneous findings associated with Kawasaki Disease include:

• Prolonged fever without other explanation
• Conjunctival injection
• Oral mucosal changes
• Changes of the hands and feet
• Cervical adenopathy
• Extreme irritability
• Arthritis during acute febrile and subacute phases
• Aseptic meningitis in patients who undergo lumbar puncture.

Question 45

What skin findings are not observed in Kawasaki Disease (KD)?

Answer 45

Bullae, vesicles, and ulcerative lesions are not observed.

Question 46

What is a common oral finding in Kawasaki Disease?

Answer 46

Red, swollen, dry, cracked lips that may bleed.

Question 47

What is a characteristic of the rash in Kawasaki Disease?

Answer 47

The rash may be pruritic.

Question 48

What is a notable eye finding in Kawasaki Disease?

Answer 48

Conjunctival injection with limbal sparing.

Question 49

What changes can occur in the hands and feet in Kawasaki Disease?

Answer 49

Erythema and edema of the hands and feet can occur.

Question 50

What is a significant finding related to the tongue in Kawasaki Disease?

Answer 50

‘Strawberry’ tongue is a significant finding.

Question 51

What is the duration of fever in Kawasaki Disease?

Answer 51

Fever lasts for 1 to 2 weeks, is daily, high spiking, and intermittent.

Question 52

What clinical features are expected during the convalescent phase of Kawasaki Disease?

Answer 52

During the convalescent phase, clinical features normalize, typically 6-8 weeks after fever onset.

Question 53

What is the phase of the disease associated with strawberry tongue and cracked lips?

Answer 53

Strawberry tongue and cracked lips are oral mucosal changes commonly observed during the acute febrile phase of KD.

Question 54

During which phases of Kawasaki Disease is arthritis most likely to occur?

Answer 54

Arthritis is most likely to occur during the acute febrile phase and the subacute phase of KD.

Question 55

What distinguishes KD-related conjunctival injection?

Answer 55

KD-related conjunctival injection is characterized by limbal sparing.

Question 56

What are Beau lines, and what do they indicate in Kawasaki Disease?

Answer 56

The transverse lines are called Beau lines, and they are a cutaneous finding associated with KD.

Question 57

What is the phase of the disease associated with erythema and edema of the hands and feet?

Answer 57

Erythema and edema of the hands and feet are most associated with the acute febrile phase of KD.

Question 58

What are the implications of the rash presentation in Kawasaki Disease for diagnosis?

Answer 58

In Kawasaki Disease, the rash is characterized by:

• Absence of bullae, vesicles, and ulcerative lesions.
• Rash may be pruritic.
• Groin erythema and desquamation may be observed.
• Classic periungual desquamation of fingers and toes, along with transverse lines (Beau lines) across fingernails.

These specific characteristics help differentiate KD from other conditions, but a skin biopsy is not useful for diagnosis as pathologic findings are nonspecific.

Question 59

How does the presentation of fever in Kawasaki Disease differ from other febrile illnesses?

Answer 59

In Kawasaki Disease, fever is characterized by:

• Daily high spiking episodes
• Intermittent nature
• Lasting for 1 to 2 weeks.