Kawasaki Disease: Symptoms and Treatment
Kawasaki disease is characterized by fever lasting at least 5 days plus four of five principal clinical features: bilateral non-exudative conjunctival injection, oral mucosal changes, polymorphous rash, extremity changes, and cervical lymphadenopathy. 1, 2
Principal Clinical Features
Fever
- High-spiking fever (typically >102.2°F/39°C, often >104°F/40°C) that persists for an average of 11 days if untreated 2
- Fever for at least 5 days is required for diagnosis, although experienced clinicians may diagnose with fewer days of fever if other criteria are present 1
Mucosal Changes
- Erythema and cracking of lips 1
- Strawberry tongue (erythematous tongue with prominent papillae) 1
- Diffuse erythema of oral and pharyngeal mucosa 1, 2
Ocular Findings
- Bilateral bulbar conjunctival injection without exudate 1, 2
- Sparing of the limbus (area immediately adjacent to the iris) 1
- Absence of photophobia and eye pain 2
Skin Manifestations
- Polymorphous rash: maculopapular, diffuse erythroderma, or erythema multiforme-like 1
- Rash typically appears within 5 days of fever onset 2, 3
Extremity Changes
- Acute phase: erythema and edema of hands and feet 1, 2
- Subacute phase: periungual desquamation (peeling around nails) beginning 2-3 weeks after fever onset 1, 2
Lymphadenopathy
- Cervical lymphadenopathy (≥1.5 cm diameter) 1
- Usually unilateral and confined to the anterior cervical triangle 1
- Least common of the principal clinical features 1
Other Clinical Manifestations
Cardiovascular
Gastrointestinal
- Diarrhea, vomiting, abdominal pain 1, 5
- Hepatitis, jaundice 1
- Gallbladder hydrops 1, 2
- Pancreatitis 1, 2
Musculoskeletal
- Arthritis, arthralgia 1
Diagnosis
Classic Kawasaki Disease
- Fever for ≥5 days plus ≥4 of the 5 principal clinical features 1, 5
- In the presence of ≥4 principal features, particularly when hand/foot changes are present, diagnosis can be made with 4 days of fever 1
Incomplete Kawasaki Disease
- Consider in children with fever ≥5 days and only 2-3 principal clinical features 5
- More common in infants <6 months who have higher risk of coronary abnormalities 4
- Diagnosis supported by laboratory findings: elevated ESR, CRP, leukocytosis 5
Treatment Protocol
Initial Treatment
- Intravenous immunoglobulin (IVIG) 2 g/kg as a single infusion 4
- High-dose aspirin (80-100 mg/kg/day divided into four doses) until patient is afebrile for at least 48 hours 4
- Treatment should be initiated within 10 days of fever onset to reduce risk of coronary artery abnormalities 4
Follow-up Treatment
- After fever resolution, transition to low-dose aspirin (3-5 mg/kg/day) as a single daily dose 4
- Duration of low-dose aspirin depends on coronary artery status 4
Management of IVIG-Resistant Disease
- For persistent or recrudescent fever 36 hours after IVIG completion (10-20% of patients) 4
- Options include second dose of IVIG (2 g/kg), infliximab, or corticosteroids 4
Monitoring and Long-term Management
Cardiac Monitoring
- Echocardiography to assess for coronary artery abnormalities 4, 5
- Frequency of monitoring depends on coronary involvement 4
- Highest risk for coronary thrombosis occurs within first 3 months, peaking at 15-45 days 4
Antiplatelet/Anticoagulation Management
- For patients with small coronary aneurysms: long-term low-dose aspirin 4
- For moderate aneurysms (4-6 mm): aspirin plus second antiplatelet agent 4
- For giant aneurysms (≥8 mm): aspirin plus warfarin or low-molecular-weight heparin 4
Common Pitfalls and Caveats
- Principal clinical features may not all be present simultaneously; careful history-taking is essential 2, 5
- Infants and older children/adolescents often have delayed diagnosis and higher risk of coronary abnormalities 5
- Measles and varicella immunizations should be deferred for 11 months after IVIG administration 4
- Annual influenza vaccination recommended for children on long-term aspirin therapy 4