What are the key clinical features to consider when diagnosing Kawasaki Disease in a child?

Key clinical features for diagnosing Kawasaki Disease in a child include:

• Persistent fever lasting at least 5 days, which is a hallmark and essential criterion for diagnosis NICE NG143 Bayers et al. 2013.
• Conjunctival injection without exudate, typically bilateral and non-purulent NICE NG143 Bayers et al. 2013.
• Changes in the lips and oral cavity such as erythema, cracked lips, strawberry tongue, and diffuse mucosal injection NICE NG143 Bayers et al. 2013Lee et al. 2022.
• Polymorphous rash, which can vary in appearance but is usually widespread NICE NG143 Bayers et al. 2013.
• Extremity changes including erythema and edema of the hands and feet in the acute phase, followed by periungual desquamation in the subacute phase NICE NG143 Bayers et al. 2013Luo et al. 2020.
• Cervical lymphadenopathy, typically unilateral and >1.5 cm in diameter NICE NG143 Bayers et al. 2013.

Additional clinical manifestations beyond the classic criteria may include irritability, arthritis or arthralgia, and gastrointestinal symptoms such as abdominal pain, vomiting, or diarrhea Lee et al. 2022. Laboratory findings supporting the diagnosis often show elevated inflammatory markers, thrombocytosis in the subacute phase, and sterile pyuria Lee et al. 2022.

In clinical practice, the diagnosis is primarily clinical, based on the presence of fever and at least four of the five principal features, but incomplete or atypical presentations are recognized, especially in infants and older children, requiring a high index of suspicion NICE NG143 Bayers et al. 2013Luo et al. 2020.