Kawasaki Disease

Question 1

Define Kawasaki disease

Answer 1

Acute, febrile, self-limiting, systemic vasculitis of unknown origin that almost exclusively affects young children

Question 2

What are the risk factors for Kawasaki disease

Answer 2

Asian ancestry, particularly Japanese
6 months - 4 years (80% <5)
Male sex
Winter/Spring months

Question 3

What are the symptoms of Kawasaki disease

Answer 3

Fever >5 days (unresponsive to analgesia)

Conjunctivitis (non-purulent, non-exudative, bilateral)
Rash
Adenopathy (lymphadenopathy)
Strawberry tongue, dry lips that bleed easily (mucositis)
Hands and feet swell (palms/sole), refusal to walk

+ irritability, poor intake, abdominal pain, nausea, diarrhoea

Question 4

What are the signs of Kawasaki disease on examination

Answer 4

General
Polymorphous erythematous rash
Swelling, redness, tenderness of palms and soles
Periungal desquamation of fingers and toes and Beau lines - transverse grooves across the nail (1-2 months after onset)

Eyes
Conjunctival infection (non-purulent/exudative)

ENT
Mucositis - dry, erythematous, fissured lips and tongue that bleeds easily
Erythema of the oral and pharyngeal mucosa
Strawberry tongue with prominent papillae and erythema
Cervical lymphadenopathy, usually unilateral

Question 5

What are the differentials for Kawasaki disease

Answer 5

Scarlet fever
Staphylococcus or streptococcus infection
Adenoviral infection
Systemic juvenile idiopathic arthritis
Rheumatic fever
Toxic shock syndrome
Staphylococcal scalded skin syndrome

Question 6

What features are required for diagnosis of Kawasaki disease

Answer 6

In addition to fever, patients must have 4 or more of the following 5 signs and symptoms for diagnosis:

polymorphous erythematous rash
non-purulent bilateral conjunctival injection
oropharyngeal changes (including diffuse hyperaemia, strawberry tongue, and lip changes
peripheral extremity changes (including erythema, oedema, induration, and desquamation)
non-purulent cervical lymphadenopathy

Question 7

What investigations should be done for Kawasaki disease

Answer 7

ECG: evaluate for conduction abnormalities

FBC: normochromic anaemia, leukocytosis, thombocytosis
CRP/ESR: raised (acute, early)

Echo: evaluate for coronary artery aneurysm, myocarditis, pericardial effusion, valvulitis
CXR: assess baseline in case of heart failure
LP: high fever + neck stiffness

Question 8

When does an echo need to be done for Kawasaki disease

Answer 8

At diagnosis
Repeat every 1-2 weeks
4-6 weeks after treatment

Question 9

What is the management for acute Kawasaki disease <10 days from onset

Answer 9

ADMIT for any suspected cases

First line: IVIg single infusion (controls inflammation, prevents coronary artery disease) + high dose oral aspirin

Second line: corticosteroids (IV methylpred OR oral pred)

third line: immunomodulatory drugs e.g. ciclosporin

Question 10

What is the management for Kawasaki disease >10 days from onset

Answer 10

Low-dose oral aspirin for 6-8 weeks

Question 11

What are the complications of Kawasaki disease

Answer 11

Coronary artery aneurysm

Cardiac: myocarditis, pericarditis, pericardial effusion, valvulitis, acute coronary events, coronary thrombosis, gangrene
Resp: pneumonitis
Musc: arthritis
GI: hepatic dysfunction, gallbladder disease, bowel ischaemia and necrosis
Aseptic meningitis

Question 12

What is the prognosis of Kawasaki disease

Answer 12

Usually a self-limiting illness
Mortality rate <0.5%
Outcome improved due to IVIG therapy

Untreated: significant morbidity and mortality due to aneurysm risk