Most U.S. mainland pediatric practitioners will see only one or two cases of Kawasaki disease (KD) in their careers, but no one wants to miss even one case.
Making the diagnosis as early as possible is important to reduce the chance of sequelae, particularly the coronary artery aneurysms that will eventually lead to 5% of overall acute coronary syndromes in adults. And because there is no “KD test,” or sometimes incomplete KD. And there are some new data that complicate this. Despite the recently updated 2017 guideline,1 most cases end up being confirmed and managed by regional “experts.” But nearly all of the approximately 6,000 KD cases/year in U.S. children younger than 5 years old start out with one or more primary care, urgent care, or ED visits.
This means that every clinician in the trenches not only needs a high index of suspicion but also needs to be at least a partial expert, too. What raises our index of suspicion? Classic data tell us we need 5 consecutive days of fever plus four or five other principal clinical findings for a KD diagnosis. The principal findings are:
1. Eyes: Bilateral bulbar nonexudative conjunctival injection.
2. Mouth: Erythema of oral/pharyngeal mucosa or cracked lips or strawberry tongue or oral mucositis.
3. Rash.
4. Hands or feet findings: Swelling/erythema or later periungual desquamation.
5. Cervical adenopathy greater than 1.4 cm, usually unilateral.