Kawasaki disease is an acute febrile vasculitis that predominantly affects young children under 5 years old. It is characterized by inflammation of blood vessels and can lead to coronary artery abnormalities if left untreated. The cause is unknown but believed to be infectious. Treatment involves intravenous immunoglobulin in the acute phase along with aspirin to prevent coronary complications. Most patients recover completely but long-term aspirin therapy may be needed for those with coronary abnormalities.

1. Prof. Dr. Saad S Al Ani Senior Pediatric Consultant Head of Pediatric Department Khorfakkan Hospital, Sharjah, UAE [email_address] Kawasaki disease

2. Introduction Kawasaki disease, formerly known as mucocutaneous lymph node syndrome or infantile polyarteritis nodosa , is an acute febrile vasculitis of childhood first described by Dr . Tomisaku Kawasaki in Japan in 1967 .

3. Idiopathic multisystem disease characterized by vasculitis of small & medium blood vessels, including coronary arteries Definition

4. Cont. Worldwide, with Asians at highest risk . Approximately 20% of untreated patients develop coronary artery abnormalities Leading cause of acquired heart disease in children in the United States and Japan .

5. Etiology The cause of the illness remains unknown , but clinical and epidemiologic features strongly support an infectious origin. ? genetically predisposed hosts

6. Epidemiology 3,000 cases are diagnosed annually in the United States. The incidence in Asian children is substantially higher than in other racial groups , . In Japan , more than 170,000 cases have been reported since the 1960s.

7. Cont. The illness occurs predominantly in young children ; 80% of patients are younger than 5 yr only occasionally are teenagers and adults affected.

8. Pathogenesis Severe vasculitis Edema of endothelial and smooth muscle cells Intense inflammatory infiltration of the vascular wall Weakens, resulting in dilatation or aneurysm formation Thrombi Fibrosis, intimal proliferation, stenosis

9. Pathogenesis (cont.) An inflammatory infiltrate in * myocardium * upper respiratory tract * pancreas *Kidney * biliary tract

10. Clinical Manifestations Kawasaki disease is generally divided into three clinical phases: 1.The acute febrile phase 2. The subacute phase 3. The convalescent phase

11. 1.The acute febrile phase - which usually lasts 1-2 wk - is characterized by fever and the other acute signs of illness.

12. 2. The subacute phase - Begins when fever and other acute signs have abated, but irritability, anorexia, and conjunctival injection may persist. - is associated with: * desquamation * thrombocytosis * development of coronary aneurysms * highest risk of sudden death. - This phase generally lasts until about the 4th wk.

13. 3.The convalescent phase -begins when all clinical signs of illness have disappeared - continues until the erythrocyte sedimentation rate (ESR) returns to normal, approximately 6-8 wk after the onset of illness.

14. Diagnostic Criteria - Fever for 5 or more days - Presence of 4 of the following : Bilateral conjunctival injection Changes in the oropharyngeal mucous membranes Changes of the peripheral extremities Rash Cervical adenopathy - Illness can’t be explained by other disease

20. Lab Features  WBC  ESR, positive CRP Anemia Mild  transaminases  albumin Sterile pyuria, aseptic meningitis  platelets by day 10-14

21. Differential Diagnosis Measles Scarlet fever Drug reactions Viral exanthems Toxic Shock Syndrome Stevens - Johnson Syndrome Systemic Onset Juvenile Rheumatoid Arthritis Staph scalded skin syndrome

22. Intravenous immunoglobulin 2 g/kg over 10-12 hr with aspirin 80-100 mg/kg/24 hr divided every 6 hr orally until 14th illness day 1.Acute stage Treatment

23. Aspirin 3-5 mg/kg once daily orally until 6-8 wk after illness onset 2.Convalescent stage

24. 3.Long-term therapy for those with coronary abnormalities Aspirin 3-5 mg/kg once daily orally ± dipyridamole 4-6 mg/kg/24 hr divided in two or three doses orally (most experts add warfarin for those patients at particularly high risk of thrombosis)

25. 4.Acute coronary thrombosis Prompt fibrinolytic therapy with tissue plasminogen activator , streptokinase , or urokinase under supervision of a pediatric cardiologist

26. Complications Recovery is complete and without apparent long-term effects for patients who do not develop coronary disease Recurrent illness occurs in only 1-3% of cases

27. Prognosis The prognosis for patients with coronary abnormalities depends on the severity of coronary disease. ,In Japan, fatality rates are now less than 0.1%. 50% of coronary artery aneurysms resolve echocardiographically by 1-2 yr after the illness

28. References Akagi T, Ogawa S, Ino T, et al : Catheter interventional treatment in Kawasaki disease : A report from the Japanese Pediatric Interventional Cardiology Investigation Group . J Pediatr 2000;137:181-6. Medline Similar articles American Heart Association Council on Cardiovascular Disease in the Young, Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease: Diagnostic guidelines for Kawasaki disease. Circulation 2001;103:335-6. Brown TJ, Crawford SE, Cornwall M, et al: CD8 T cells and macrophages infiltrate coronary artery aneurysms in acute Kawasaki disease. J Infect Dis 2001;184:940-3. Medline Similar articles Chang RKR: Hospitalizations for Kawasaki disease among children in the United States, 1988-1997. Pediatrics 2002;109:e87. Han RK, Silverman ED, Newman A, et al: Management and outcome of persistent or recurrent fever after initial intravenous gammaglobulin therapy in acute Kawasaki disease. Arch Pediatr Adolesc Med 2000;154:694-9. Medline Similar articles Rowley AH, Shulman ST, Mask CA, et al: IgA plasma cell infiltration of proximal respiratory tract, pancreas, kidney, and coronary artery in acute Kawasaki disease. J Infect Dis 2000;182:1183-91. Medline Similar articles Stockheim JA, Innocentini N, Shulman ST: Kawasaki disease in older children and adolescents. J Pediatr 2000;137:250-2. Medline Similar articles

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