Infectious Disease: Kawasakis Disease

Question 1

Definition

Answer 1

Acute, systemic vasculitis of unknown cause that predominantly affects children under the age of 5
Also known as mucocutaneous lymph node syndrome

Question 2

Epidemiology

Answer 2

< 5 years old
Ethnicity: North-East Asia descent e.g. Japan and Korea
Sex: more prevalent in males by a factor or 1.5
Family history: siblings are 10-20 times more likely to develop Kawasaki disease than the general population

Question 3

Pathophysiology

Answer 3

It is thought to be triggered by an unknown respiratory agent (possibly infection) , which triggers a cytokine reaction and the activation of oligoclonal IgA plasma cells , which are found in coronary artery biopsies as well as the respiratory tract. This activation, mainly affects medium-sized arteries , particularly the coronary arteries. This places a significant and severe risk of developing coronary artery aneurysms over weeks to months

Question 4

Signs (CREAM)

Answer 4

ACUTE FEBRILE STAGE (1-2 WEEKS): Persistently high fever > 39 degrees: refractory to anitpyretic and lasting > 5 days
C- Conjunctival infection: red-eye without exudate or pain
R- Rash (Polymorphous) : morbilliform, maculopapular or scarlatiniform
E- Edema/Erythema:
A- Adenopathy : Cervical lymphadenopathy
M- Mucosa/Myocarditis (Or pericarditis)
- Strawberry tongue: red, swollen and covered in small bumps,
- Dry cracked lips,
- Pharyngeal/Lip redness
SUBACUTE STAGE (2-4 WEEKS)
- Fever, Rash and lymphadenopathy resolved
- Desquamation (Often periungal)
- Cardiac abnormalities: Coronary artery involvement -> myocardial infarction sudden cardiac death
CONVALESCENT STAGE (4-8 WEEKS)
- Cardiac aneurysms may enlarge

Question 5

Symptoms

Answer 5

Irritability
Pain in more than 1 joint
Swelling in hands and feet
Redness of the palms and soles: these may peel later

Question 6

Diagnostic criteria

Answer 6

NICE states that a child may have Kawasaki disease if they have a fever for 5 days plus any 1 other key symptom :

• Bilateral conjunctival infection
• Changes to the mouth or throat: such as dry, red, cracked lips, red, swollen tongue
• Changes to the hands and feet: swollen or painful hands or feet, or red or peeling skin on the palms/soles
• Polymorphous rash
• Cervical lymphadenopathy

Question 7

Investigations

Answer 7

ESR/CRP: high
FBC: leukocytosis, anaemia + thrombocytosis
Echo: identify coronary artery aneurysms (serious complication of the disease
ECG: Prolonged PR interval, deep Q waves, low voltage, ST-T changes, and arrhythmias may suggest myocardial damage.

Question 8

Treatment

Answer 8

FIRST LINE = IV immunoglobulin (IVIG) given within first 10 days of illness, symptoms improve in 36 hours
- Aspirin: high doses first then lower as child is afebrile
- Follow up echo

SECOND LINE = Corticosteroids if IVIG ineffective

Question 9

Complications

Answer 9

Coronary artery aneurysms or dilation: Children will be on low-dose aspirin to mitigate for any thromboses that may form in the coronary arteries during this time. Small aneurysms may resolve in 60% of cases.
Myocarditis : leading to heart failure
Pericarditis
Reye’s syndrome : aspirin use in under 16 year olds is usually avoided due to the risk of developing a rare syndrome, characterised by liver and brain damage. Symptoms include lethargy and persistent vomiting.