Diagnosis of Kawasaki Disease

Kawasaki disease can only be diagnosed clinically (by medical signs and symptoms), as there exists no specific laboratory test that can tell if someone has it. It is normally difficult to establish the diagnosis, especially early in the course of illness, and frequently children are not diagnosed until they have seen their doctor several times, or visited a number of different health care providers. Many other serious illnesses can cause similar symptoms, and must be considered in the differential diagnosis, including scarlet fever, toxic shock syndrome, and juvenile idiopathic arthritis.

Classically, five days of fever plus four of five diagnostic criteria must be met in order to establish the diagnosis. The criteria are: (1) erythema of the lips or oral cavity or cracking of the lips; (2) rash on the trunk; (3) swelling or erythema of the hands or feet; (4) red eyes (conjunctival infection) (5) swollen lymph node in the neck of at least 15 millimeters.

Many children, especially infants, eventually diagnosed with Kawasaki disease do not exhibit all of the above criteria. In fact, many experts now recommend treating for Kawasaki disease even if only three days of fever have passed and at least three diagnostic criteria are present, especially if other tests reveal abnormalities consistent with Kawasaki disease. In addition, the diagnosis can be made purely by the detection of coronary artery aneurysms in the proper clinical setting.