Kawasaki Disease Diagnostic Criteria

Why Use

The most common and dangerous long-term sequelae of KD are CA abnormalities (aneurysms or ectasia) that develop in up to 25% of untreated children and may lead to sudden death or ischemic heart disease ( Newburger 2004 ).

When to Use

Children with several days of unexplained fever associated with any of the principal clinical features of Kawasaki Disease (KD).

Formula

Pearls / Pitfalls

The Kawasaki Disease Criteria are widely used for the diagnosis of Kawasaki Disease, also known as mucocutaneous lymph node syndrome, adopted by the American Heart Association (AHA) and endorsed by the American Academy of Pediatrics (APA) ( Newburger 2004 ). There is no diagnostic laboratory test. The diagnosis is clinical. Clinical findings do not commonly manifest simultaneously and there is no typical order of appearance. Repeated examinations and close history-taking are important. Can be confused with other infectious exanthema of childhood, and concurrent viral infections are common. Non-specific symptoms commonly occur in children, including arthritis, vomiting, diarrhea, abdominal pain, irritability, cough, rhinorrhea and decreased oral intake ( Baker 2009 ). Although there is no diagnostic laboratory test, elevated WBC and platelet counts, transaminases, and acute phase reactants, as well as anemia and pyuria, can be suggestive of KD. Points to keep in mind: It is suspected that at least 10% of patients who develop coronary artery (CA) abnormalities fail to meet the criteria for KD ( Sundel 2002 ). The criteria may fail to diagnose a substantial number of patients. Patients suspected of having KD who do not fulfill the diagnostic criteria may have incomplete (atypical) KD. Children with incomplete KD, whose diagnosis is delayed, are more likely to develop CA abnormalities. The AHA and AAP have developed criteria to help diagnose and guide treatment in incomplete KD ( Newburger 2004 ).

Management

Prompt treatment in the acute phase with intravenous immune globulin (IVIG) and aspirin reduces the prevalence of the development of CA abnormalities and subsequent mortality and morbidity. The two appear to have an additive effect ( Newburger 2004 ). Treatment should be instituted within the first 10 days of the illness and if possible within 7 days of illness. IVIG The mechanism is unknown, but believed to be linked to the anti-inflammatory effect. Different dosing regimens exist. A single, higher dose is most effective ( Newburger 1991 ). Based on timing of development of the CA abnormalities, therapy should be instituted within the first 10 days of illness and, if possible, within 7 days of illness. IVIG should be considered in children presenting after the 10th day of illness if they have persistent fever without other explanation or aneurysms and ongoing systemic inflammation, as manifested by elevated ESR or CRP ( Newburger 2004 ). High dose aspirin Administered with IVIG. Has anti-inflammatory effects, but does not appear to lower the frequency of development of CA abnormalities ( Newburger 2004 ). Dosing regimens vary. The risk of Reye Syndrome must be considered and weighed against the benefits of therapy. Annual influenza vaccination is recommended in patients taking aspirin long term. The risks and benefits of varicella vaccination in children receiving long term aspirin therapy must be considered. Ibuprofen should be avoided because it antagonizes the irreversible platelet inhibition that is induced by aspirin. Steroids may be considered as adjuvant treatment to help decrease the rate of CA abnormalities, although they are not routinely used. Management algorithms exist for the treatment of incomplete and refractory KD.

Critical Actions

Suspect KD in any patient (particularly children <5 years old) presenting with several days of otherwise unexplained fever. Early diagnosis and treatment during the acute phase is essential in preventing CA abnormalities.

Advice

If the diagnosis of KD is made in the acute phase, treatment should be initiated to prevent CA abnormalities. If the patient does not meet the criteria for KD, consider incomplete KD.