Kawasaki disease (mucocutaneous lymph node syndrome) Flashcards
What is some epidemiology of Kawasaki disease?
c. 8/100,000 in the UK
80% of cases happen to children aged 6m-5yrs
Leading cause of acquired heart disease in developing countries
What is the aetiology and pathophysiology of Kawasaki disease?
Is an acute inflammatory vasculitis of medium sized arteries (hence coronary artery involvement and acquired heart disease)
Origin currently unknown - probably some infective agent
What are the criteria for Kawasaki’s?
High fever (38 o +) ≥5 days (necessary condition, + 4+ additional criteria)
i) Acute changes of extremities – erythema of palms, soles, oedema of hands/feet
ii) Subacute changes in extremities – peeling of fingers and toes in weeks 2-3
iii) Polymorphous exanthem – diffused maculopapular rash, appearing within 5 days of fever, usually trunk, extremities and perineal region
iv) Bilateral bulbar conjunctival injection – tender, swollen and inflamed sclera (red eye)
v) Changes in lips and oral cavity – erythema, cracking, strawberry tongue
vi) Cervical lymphadenopathy - >1.5cm, usually unilateral
vii) Coronary artery disease – Dx by echo or angiogram
Diagnosis made on these criteria + exclusion of other possible causes with standard investigations e.g. measles serology
What is the mnemonic to remember the symptoms of Kawasaki’s?
MYHEART
i) Mucosal involvement - lips/tongue
ii) Hands and feed – odema
iii) Eyes – conjunctivitis
iv) Adenopathy - cervical, unilateral
v) Rash - truncal, polymorphic
vi) Temperature - 5 days not remitting high fever
What are some differential diagnoses for Kawasaki’s?
Scarlet fever – fever + distinctive pink rash
Measles – fever + distinctive red-brown spots
Glandular fever – fever + swollen lymph nodes
Stevens-johnson syndrome – drug allergy
Viral meningitis
Lupus
Vasculitis
Strep throat
What is the standard treatment for Kawasaki’s?
IVIg
High dose and improvement seen within first 24hrs – if fever doesn’t respond, then second dose advised (rarely a third is needed)
Most useful within 7 days of fever onset (in terms of aneurysm prevention)
What are some possible risks with IVIg?
i) HTN → coronary or neurology thrombotic events (because you go into a prothombotic state)
ii) Aseptic meningitis – rare but well recognised
iii) Anaphylaxis; rash
What other treatments do you give?
Aspirin - minimise cardiac complications
High doses until fever subsides (used in conjunction with IVIG?) then low dose at home for 2m to reduce clotting risk
What is a risk of high dose aspirin in paeds?
Use is associated with Reye’s syndrome
i) 90% of cases of Reye’s have aspirin as a component (first noted in the USA because of their use of aspirin as 1st line analgesia)
ii) Rapid, progressive hepatic encephalopathy – N+V, confusion, personality change, seizure, LoC
iii) Begins shortly after recovery from viral infection – flu or chicken pox (vaccination of varicella and influenza are thus important in someone with Kawasaki’s + aspirin treatment)
How should you follow someone with Kawasaki’s up?
ECG and Echo – to check for heart abnormalities which can appear in weeks 1-2
Tachycardia; Pericardial effusion; myocarditis; Aneurysm
What’s the prognosis of Kawasaki’s?
Coronary aneurysm in 20-25% if untreated; leading cause of acquired heart disease in children under 5 in developed countries; fatality related to cardiac problems is 2-3%
Death in 20-40%; 1/3 that survive get brain damage
Good with timely intervention but complications (aneurysm – heart attack, rupture)
50% cardiac impairment, mild mitral regurgitation
15-25% untreated - coronary artery aneurysm; 5% in treated
Mortality 0.1-4%
Children under 1 are more at risk of serious complications
Any cardiac problems in acute stages means increased risk of adult problems – specialist f/u