Fever persisting at least five days*: the fever is generally high and spiking (often to 40°C [104°F] or higher) and persists in untreated patients for one to two weeks or longer.
Presence of at least four of the following five principal features†:
	Changes in extremities: these changes are distinctive and acutely include redness, swelling and, sometimes, induration of the hands and feet. One to three weeks after the onset of fever, desquamation of the fingers and toes occurs. Approximately one to two months after the onset of fever, Beau's lines (white lines across the fingernails) may appear.
	Polymorphic exanthem: the skin eruption involves the trunk and extremities and may have several forms, including urticarial exanthem, a morbilliform maculopapular eruption (occasionally with target lesions) or a diffuse scarlatiniform rash. Bullae and vesicles are not seen. The rash usually appears within five days after the onset of fever.
	Bilateral conjunctival injection: the bulbar conjunctivae, rather than the palpebral or tarsal conjunctivae, are involved. Typically, the limbic region is spared. The conjunctival injection is not associated with an exudate and is usually painless.
	Changes in the lips and oral cavity: these changes include strawberry tongue, redness and cracking of the lips, and erythema of the oropharyngeal mucosa. Ulcerative lesions are not seen.
	Cervical lymphadenopathy (at least one lymph node with a diameter of 1.5 cm or greater): the lymphadenopathy is usually unilateral, with firm and slightly tender nodes.
Exclusion of other diseases with similar findings.