Kawasaki disease (mucocutaneous lymph node syndrome) is a form of vasculitis identified by an acute febrile illness with multiple systems affected. The cause is unknown, but autoimmunity, infection, and genetic predisposition are believed to be involved. It affects mostly children between ages 3 months and 8 years; 80% are younger than age 5. It occurs more commonly in Japanese children or those of Japanese decent. It has seasonal epidemics, usually in late winter and early spring. It was first described in 1967 by Dr. Tomisaku Kawasaki in Japan.
Although Kawasaki disease is a multisystem disease, the cardiovascular system appears to be the primary site with coronary artery vasculitis, aneurysm development, thrombosis, and myocardial thrombosis progressing over days to weeks. Approximately 15% to 25% of patients develop cardiac complications (coronary thrombosis or rupture, myocardial infarction, heart failure, vasculitis of the aorta or peripheral arteries); however mortality is low.
Incidence and Risk Factors:
By far, the highest incidence of Kawasaki disease occurs in Japan (175 per 100,000), though its incidence in the United States is increasing. Kawasaki disease is predominantly a disease of young children, with 80% of patients younger than 5 years of age.
The disease affects boys more than girls. Approximately 2000-4000 cases are identified in the United States each year.
The causative agent of Kawasaki disease is still unknown, but current theories center primarily on immunological causes for the disease. Evidence increasingly points to an infectious etiology, but debate continues on whether the cause is a conventional antigenic substance or a superantigen. Per a Children’s Hospital Boston / Harvard Medical school information page on the disease, “Some studies have found associations between the occurrence of Kawasaki disease and recent exposure to carpet cleaning or residence near a body of stagnant water; however, cause and effect have not been established.”
An association has been identified with an SNP in the ITPKC gene, which codes an enzyme that negatively regulates T-cell activation. An additional factor that suggests genetic susceptibility is the fact that regardless of where they are living, Japanese children are more likely than other children to contract the disease. The HLA-B51 serotype has been found to be associated with endemic instances of the disease.
Signs and symptoms:
Stage I – Acute Febrile Phase (First 10 days)
- The child appears severely ill and irritable.
- Major diagnostic criteria established by the Centers for Disease Control and Prevention (CDC) are as follows:
a. High, spiking fever for 5 days or more.
b. Bilateral conjunctival injection.
c. Oropharyngeal erythema, “Strawberry “ tongue, or red dry lips.
d. Erythema and edema of hands and feet, periungal desquamation.
e. Erythematous generalized rash.
f. Cervical lymphadenopathy greather than 0.6 inch (1.5cm)
- Pericarditis, myocarditis, cardiomegaly, heart failure, and pleural effusion.
- Other associated findings include meningitis, arthritis, sterile pyuria, vomiting, and diarrhea.
Stage II – Subacute Phase (Days 11 to 25)
- Acute symptoms of stage I subside as temperature returns normal. The child remains irritable and anorectic.
- Dry, cracked lips with fissures.
- Desquamation of toes and fingers.
- Coronary thrombus, aneurysm, myocardial infarction, and heart failure.
- Thrombocytosis peaks at 2 weeks.
Stage III – Convalescent Phase (Until sedimentation rate and platelet count normalize)
- The child appears well.
- Transverse grooves of fingers and toenails (Beau’s lines).
- Coronary thrombosis, aneurysms may occur.
- The diagnostic of Kawasaki disease is based on clinical manifestations. The CDC requires that fever and four of the six other criteria listed above in stage I be demonstrated.
- Electrocardiogram, echocardiogram, cardiac catheterization, and angiocarddiography may be required to diagnose cardiac abnormalities.
- Although there are no specific laboratory tests, the following may help support diagnosis or rule out other disease.
1. CBC – leukocytosis during acute stage.
2. Erythrocytes and hemoglobin – slight decrease.
3. Platelet count – increased during second to fourth week of illness.
4. IgM, IgA, IgG, and IgF – transiently elevated.
5. Urine – protein and leukocytes present.
6. Acute phase reactants (ESR, C-reactive protein, alpha I antitrypsin) are elevated during the acute phase.
7. Myocardial enzyme levels (serum CK-MB) suggest MI if elevated.
8. Liver enzymes (AST, ALT) – moderately elevated.
9. Lipid profile – low high density lipoprotein and high triglyceride level.
- Immune globulin (gamma globulin) I.V. therapy – IVGG (2g/kg/day) is initiated during stage I in one 8 to 10 hour infusion to reduce the incidence of coronary artery abnormalities.
- Aspirin therapy
- Thrombolytic therapy may be required during stages I, II, or III.
- Monitor pain level and child’s response to analgesics.
- Institute continual cardiac monitoring and assessment for complications; report arrhythmias.
- Take vital signs as directed by condition; report abnormalities.
- Assess for signs of myocarditis (tachycardia, gallop rhythm, chest pain).
- Monitor for heart failure (dyspnea, nasal flaring, grunting, retractions, cyanosis, orthopnea, crackles, moist respirations, distended jugular veins, edema).
- Closely monitor intake and output, and administer oral and I.V fluids as ordered.
- Monitor hydration staus by checking skin turgor, weight, urinary output, specific gravity, and presence of tears.
- Observe mouth and skin frequently for signs of infection.
- Allow the child periods of uninterrupted rest. Offer pain medication routinely rather than as needed during stage I. Avoid NSAIDS if the child is in aspirin therapy.
- Perform comfort measures related to the eyes.
- Conjunctivities can cause photosensitivity, so darken the room, offer sunglasses.
- Apply cool compress.
- Discourage rubbing the eyes.
- Instill artificial tears to soothe conjunctiva.
- Monitor temperature every 4 hours. Provide sponge bath if temperature above normal.
- Perform passive range of motion exercises every 4 hours while the child is awake because movement may be restricted.
- Provide quiet and peaceful environment with diversional activities.
- Provide care measures for oral mucous membrane.
- Offer cool liquids like ice chips and ice pops.
- Use soft toothbrush only.
- Apply petroleum jelly to dried, cracked lips.
- Provide skin measures to improve skin integrity.
- Avoid use of soap because it tends to dry skin and make it more likely to breakdown.
- Elevate edematous extremities.
- Use smooth sheets.
- Apply emollients to skin as ordered.
- Protect peeling of skin, observe for signs of infection.
- Offer clear liquids every hour when the child is awake.
- Encourage the child to eat meals and snack with adequate protein.
- Infuse I.V fluids through a volume control device if dehydration is present, and check the site and amount hourly.
- Explain all procedures to the child and family.
- Encourage the parents and child to verbalize their concerns, fears, and questions.
- Practice relaxation techniques with child, such as relaxation breathing, guided imagery, and distraction.
- Prepare the child for cardiac surgery or thrombolytic therapy if complications develop.
- Keep the family informed about progress and reinforce stages and prognosis.
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