Clinical features of Kawasaki disease

Children may present with a ‘complete’ set of clinical features for Kawasaki disease, or the clinician may have a strong clinical suspicion of Kawasaki disease, despite an ‘incomplete’ set of clinical features (ie fewer features than required for the diagnosis). A high index of suspicion is required for diagnosing incomplete Kawasaki disease; this is important because children with this type may be at higher risk of developing coronary artery aneurysms than those with complete Kawasaki disease.

Note: Maintain a high index of suspicion for incomplete Kawasaki disease because children with this type may be at higher risk of developing coronary artery aneurysms than those with complete Kawasaki disease.
Complete or ‘classic’ Kawasaki disease is diagnosed on criteria outlined in Criteria for the diagnosis of Kawasaki disease.
Incomplete Kawasaki disease is diagnosed when there is a strong clinical suspicion of Kawasaki disease but the patient does not fulfil the criteria for diagnosis of Kawasaki disease. Treat children as for Kawasaki disease if they meet the criteria for incomplete Kawasaki disease in Criteria for the diagnosis of incomplete Kawasaki disease.
Figure 1. Criteria for the diagnosis of Kawasaki disease.

McCrindle, 2017

Kawasaki disease is diagnosed in children with fever for 5 or more days plus either:

  • 4 or more principal clinical criteria during the course of the illness
  • fewer than 4 principal clinical criteria plus coronary artery lesions on echocardiogram [NB1].

Principal clinical criteria:

  • bilateral nonexudative conjunctivitis
  • cervical lymphadenopathy (greater than 1.5 cm diameter), usually unilateral
  • polymorphous rash
  • changes to the lips and oral cavity including erythema, cracked lips and strawberry tongue
  • changes in the extremities—in the acute phase, erythema of palms and soles and oedema of hands and feet; in the subacute phase, desquamation of hands and feet.

Other clinical features may include:

  • preceding diarrhoeal illness
  • aseptic meningitis
  • sterile pyuria, uveitis
  • hydropic distension of the gallbladder.
Note:

NB1: If Kawasaki disease is suspected, echocardiography should be performed as early as possible but should not delay initiation of treatment. Children with echocardiographic coronary artery lesions are considered ‘high risk’.

Figure 2. Criteria for the diagnosis of incomplete Kawasaki disease.

McCrindle, 2017

Suspect incomplete Kawasaki disease in:

  • children with fever for 5 or more days, but only 2 or 3 of the principal clinical criteria
  • infants with fever for 7 or more days without explanation.

The diagnosis of incomplete Kawasaki disease is made when these infants or children have both:

  • elevated inflammatory markers
    • ESR 40 mm/hour or more
    • serum CRP concentration 30 mg/L or more
  • at least 3 of the following laboratory findings
    • anaemia (for age)
    • platelets 450 × 109/L or higher after day 7 of fever
    • serum albumin less than 30 g/L
    • elevated serum ALT concentration
    • WCC 15 × 109/L or higher
    • urinalysis 10 or more white cells/high power field

Infants or children who do not have these features should undergo serial clinical and laboratory re-evaluation if fever persists.

Note:

ALT = alanine aminotransferase; CRP = C-reactive protein; ESR = erythrocyte sedimentation rate; WCC = white cell count