Kawasaki Disease Diagnosis and Management

Clinical Presentation and Diagnostic Criteria

The American Heart Association recommends that a diagnosis of Kawasaki disease requires fever for ≥5 days plus ≥4 of the following 5 principal features: bilateral bulbar conjunctival injection, oral mucosal changes, polymorphous rash, extremity changes, and cervical lymphadenopathy 1, 3
The American Academy of Pediatrics notes that fever for ≥5 days is the cornerstone diagnostic feature of Kawasaki disease 1, 3
The American College of Cardiology states that rash on palms and soles represents the extremity changes that is one of the five principal clinical features of Kawasaki disease 1, 4
Elevated WBC count (leukocytosis with neutrophil predominance) is typical in Kawasaki disease, with approximately 50% of patients having counts >15,000/mm³ 5
Elevated ESR is nearly universal in Kawasaki disease, often >40 mm/hour and commonly ≥100 mm/hour 6, 5
Thrombocytosis (high platelets) typically appears in the second week after fever onset, which fits the presentation of Kawasaki disease 1

The American Heart Association recommends that laboratory tests for Kawasaki disease include leukocytosis with immature and mature granulocyte predominance, elevated acute phase reactants (ESR and CRP), and thrombocytosis appearing after day 7 of illness 5, 6
Additional supportive findings may include anemia, hypoalbuminemia, elevated ALT, and sterile pyuria 3, 7

The American Academy of Pediatrics notes that without treatment, 15-25% of children develop coronary artery aneurysms or ectasia, which can lead to myocardial infarction, sudden death, or ischemic heart disease 2
Treatment with IVIG within 10 days of fever onset reduces the risk of coronary artery aneurysms from 25% to approximately 5% 4

The American College of Cardiology recommends that echocardiography be obtained immediately in patients with suspected Kawasaki disease 1, 3
The American Heart Association states that treatment with IVIG 2 g/kg and high-dose aspirin 80-100 mg/kg/day should be initiated without delay in patients with Kawasaki disease 2, 1
The American Academy of Pediatrics notes that treatment should begin as soon as the diagnosis is suspected, ideally within 10 days of fever onset 2, 4

The American Heart Association recommends that patients with Kawasaki disease be risk-stratified based on factors such as age <1 year, male sex, and specific laboratory thresholds (WBC >12,000/mm³, platelets after day 7 >450,000/mm³, hemoglobin <10 g/dL, albumin <3.5 g/dL) 7, 5, 6
All patients diagnosed with Kawasaki disease should receive IVIG regardless of risk stratification, as scoring systems have imperfect predictive value 7