A rare childhood illness, Kawasaki disease is a multisystem disorder involving vasculitis—inflammation of the inner lining of the blood vessels—that can harm the coronary arteries. According to the American Heart Association, Kawasaki disease is a major cause of heart disease in children, with about 4,000 children diagnosed in the United States each year. In fact, Kawasaki disease is the leading cause of acquired heart disease in children in the United States and Japan.
The disease is most common in children ages 1 to 2 and is less common in children older than age 8. It generally affects boys twice as often as girls. Kawasaki disease is seen more often in Japan than in any other country. And in the United States, it's diagnosed more frequently in children of Asian or Asian American heritage, although Kawasaki disease can occur in any racial or ethnic group.
In the pediatric population, Kawasaki disease remains significantly prevalent. That's why it's important for nurses to review all aspects of the disease. In this article, you'll find a review of the disease course, as well as a discussion of the symptoms, diagnosis, possible complications, and treatment of Kawasaki disease.
Infection leads to inflammation
The etiology of Kawasaki disease is unknown; however, scientists believe that it's caused by an unidentified infectious agent. Kawasaki disease doesn't appear to be contagious, nor does it appear to be hereditary.
The disease can weaken the wall of one or more of the coronary arteries, causing them to bulge or balloon out (aneurysm). Blood clots may form in the ballooned area, potentially blocking blood flow through the coronary artery. When this happens, the heart muscle won't receive an adequate supply of oxygen-rich blood, which can cause permanent damage. The disease may also cause inflammation of the myocardium and/or pericardium, irregular heart rhythms, and heart valve problems. A child who has damaged coronary arteries may be more likely to experience a myocardial infarction (MI) as a young adult.
Phases times three
Kawasaki disease occurs in three phases: acute, subacute, and convalescent.
The acute phase lasts from 1 to 2 weeks and is characterized by:
* high fever that persists for more than 5 days
* swollen hands and feet
* red throat or tongue (strawberry tongue)
* spotty, bright red rash on the back, chest, abdomen, and/or groin
* swollen lymph glands in the neck
* hepatic dysfunction.
The subacute phase, lasting 2 to 4 weeks, is characterized by:
* cracked lips
* desquamation of the skin on the tips of the fingers and toes
* joint pain
* cardiac disease.
The convalescent phase lasts 6 to 8 weeks after the onset of the disease. The child appears normal, but there are lingering signs of inflammation.
Diagnosis and treatment
Kawasaki disease can be difficult to diagnose because there isn't a specific diagnostic test for it. It's diagnosed when a child has a high, spiking fever over 102.2° F (39° C) for 5 days or longer, along with four of the other acute phase symptoms (see Picturing Kawasaki disease symptoms). When fewer than four symptoms are present, but angiography or echocardiography reveals coronary artery abnormalities, Kawasaki disease is also diagnosed.
Treatment for Kawasaki disease starts in the hospital. It may include high doses of I.V. immunoglobulin (IVIG) before the 10th day of fever to reduce the incidence of aneurysm. If the child doesn't respond well to IVIG, corticosteroids or the monoclonal antibody infliximab may be used. High doses of aspirin may also be given to help relieve pain and fever, and lower the risk of blood clots. Early treatment is important because it shortens the illness and lowers the chances of heart damage.
Those patients who develop an aneurysm will require regular monitoring by echocardiography (and sometimes by coronary angiography) and should continue taking aspirin. If the aneurysm is large, an anticoagulant, such as clopidogrel or warfarin, is usually added.
If coronary stenosis develops, bypass surgery or catheter intervention (usually a rotation ablation) may become necessary. In cases of serious coronary lesions, there's a risk of MI, so it's important to monitor these patients regularly for the development of adverse symptoms.
Children are usually hospitalized for 3 or more days, depending on the presence of cardiac lesions and how long the fever persists. Most children recover fully and have no long-term problems. Careful monitoring for cardiac disease continues for several weeks or months. If the disease causes heart damage, the child may need more treatment and follow-up tests.
When caring for a child with Kawasaki disease, take his or her temperature every 4 hours and before each dose of aspirin. Carefully assess the child's extremities for edema, redness, and desquamation every 8 hours. Examine the child's eyes for conjunctivitis and the mucous membranes for inflammation. Monitor his or her dietary and fluid intake, and weigh the child daily. Assess the child's heart sounds and rhythm, and also monitor for complications, such as an aneurysm; adverse reactions of aspirin therapy, such as gastrointestinal upset and bleeding; and adverse reactions of IVIG therapy, such as elevated BP, chest tightness, and facial flushing.
Ensure that the child's parents have accurate information about the usual course of the disease, including the importance of follow-up monitoring and the circumstances under which they should contact the child's healthcare provider. The administration of the measles-mumps-rubella and varicella vaccines should be delayed for 11 months after the administration of IVIG because the child's body might not produce the appropriate number of antibodies.
This way to positive outcomes
Early treatment of Kawasaki disease is important because it shortens the illness and lowers the risk of heart disease. However, the diagnosis of Kawasaki disease remains difficult. The clinician must have a high degree of suspicion for the disease so that he or she may ask the appropriate medical history questions for diagnosis. Nurses must be aware of the presentation, symptoms, and treatment of Kawasaki disease to deliver the best care for these pediatric patients.
Learn more about it
Ball J, Bindler R, Cowen K. Principles of Pediatric Nursing. Caring for Children. 5th ed. Upper Saddle River, NJ: Pearson/Prentice Hall; 2012:632–634.
Hockenberry MJ, Wilson D. Wong's Nursing Care of Infants and Children. 9th ed. St. Louis, MO: Elsevier; 2011:1386–1390.
Scheinfeld NS. Kawasaki disease. http://emedicine.medscape.com/article/965367-overview.