Pediatric Examination and Board Review by Robert Daum, Jason Canel Read Free Book Online Page B

fever and is characterized by a decrease in the rash and fever with the onset of desquamation of the fingers and toes. Thrombocytosis peaks at 2-4 weeks into the course of the disease. It is during this phase that coronary artery aneurysms usually become evident.
    10. (C) Coronary artery aneurysms are the most feared complication of Kawasaki disease and occur in up to 15-25% of untreated patients ( Figure 4-3 ). They are a result of the panvasculitis resulting in aneurysmal transformation of the coronary arteries and may be seen as early as 7 days after the onset of the fever. Their incidence peaks at 3-4 weeks and they are seldom found after 8 weeks into the course of the disease. Giant aneurysms are described as having a diameter greater than 8 mm and are associated with increased mortality and morbidity. Patients with aneurysms also have a higher incidence of developing stenoses leading to myocardial ischemia and infarction with long-term follow-up. Coronary artery rupture is the most common cause of mortality in the subacute phase; myocarditis, heart failure, and arrhythmias are the most common causes of mortality in the acute phase within the first 10 days after the onset of fever. Risk factors for the development of coronary artery aneurysms include male gender, age younger than 1 year, hemoglobin less than 10 g/dL, white blood cell count greater than 30,000/mm 3 , ESR greater than 101 mm/hour, and prolonged fever. Echocardiography is recommended for assessment of coronary artery involvement with Kawasaki disease. The most recent recommendations suggest that an echocardiogram is obtained at diagnosis, and if no coronary disease is seen, then it should be repeated in 6-8 weeks. If coronary artery involvement is documented, then follow-up should be more frequent based on the extent of disease.
    11. (A) The management of Kawasaki disease includes high-dose aspirin, which is given during the acute phase, followed by low-dose aspirin for 6-8 weeks. This is given for antithrombotic effect while thrombocytosis is present. IVIG is administered within the first 10 days of the disease at a dose of 2 g/kg and may be repeated if fever persists following this therapy. The use of IVIG decreases the incidence of coronary artery aneurysms to less than 5%. If aneurysms persist past 2 months, then aspirin or other anticlotting agents should be continued. The use of steroids is not indicated for uncomplicated Kawasaki disease.

    FIGURE 4-3. Parasternal short-axis images of coronary artery aneurysms associated with Kawasaki disease. A. The proximal left coronary artery (LCA) is diffusely dilated and aneurysmal. B. A proximal right coronary artery aneurysm ( arrow ) is shown. Ao, aorta, LA, left atrium. (Reproduced, with permission, from Fuster V, O’Rourke RA, Walsh RA, et al. Hurst's the Heart, 12th ed. New York: McGraw-Hill, Fig. 16-140.)
     
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    12. (A) The most likely diagnosis in this situation is infective endocarditis. This is an inflammatory disorder of the heart resulting from an infection. The signs and symptoms of infective endocarditis include acute findings of fever, anorexia, weight loss, pallor, night sweats, myalgias, and new onset of a heart murmur, usually as a result of valve disease from infection. Later findings result from embolic phenomena and include splinter hemorrhages, Roth spots (retinal hemorrhages), Janeway lesions, Osler nodes, splenomegaly, clubbing, arthralgias, arthritis, glomerulonephritis, and aseptic meningitis ( Figure 4-4 ). The pathogenesis of infective endocarditis results from the initial setting of a jet of blood or turbulence within the heart leading to endothelial damage and formation of a sterile clot or vegetation. This serves as a nidus for bacterial infection.

    FIGURE 4-4. Selected peripheral manifestations of infective endocarditis. A. Splinter hemorrhages are linear hemorrhages under the nails that do not reach the nail margin. They are often red for the first two days and brownish