A 10-month-old girl presents with high fever for 8 days, which is remittent in nature and associated with irritability. She was treated with antibiotics for the past 4 days, with little or no improvement in symptoms. She was previously well and was breastfed up to 6 months of age.
WBC/DC: 13,500/mm3 N: 70%, L: 25% Hb: 12g/dl Platelets: 620,000/mm3
Her blood and urine cultures are negative. The chest x-ray appears normal.
The x-ray appears normal, with no evidence of pharyngeal soft-tissue thickening.
The echocardiogram shows perivascular brightening and cuffing of the right coronary artery, and irregularity of the inner wall of the left anterior descending artery. No structural or valvular cardiac defects are noted, while the ejection fraction is > 70%