Refractory Kawasaki Disease in Infants Complicated with Giant Coronary Artery Aneurysms and Takayasu Arteritis: A Rare Case Report and Literature Review.

Kawasaki disease (KD) is a common acute systemic vasculitis in children.10% to 20% of children present with refractory KD, and a few critically ill children may develop Kawasaki disease shock syndrome (KDSS) or macrophage activation syndrome (MAS). Coronary artery aneurysm (CAA) is the most serious complication of KD, and giant coronary artery aneurysm (GCAA) has an extremely poor prognosis. Takayasu arteritis (TAK) is a chronic granulomatous vasculitis mainly involving the aorta and its branches. It is extremely rare in infants, with no specific early symptoms and prone to delayed diagnosis. The combination of infant KD and TAK is extremely rare, as there is overlap in vascular involvement, making it difficult to differentiate clinically. This article reports the case of a 45-day-old male infant diagnosed with refractory KD, accompanied by KDSS and MAS. After conventional treatment, the condition relapsed and progressed to a GCAA, and subsequently TAK occurred. The complete clinical diagnosis and treatment process of the case will be elaborated in detail here. At the same time, based on the literature review, the diagnosis and treatment of this disease are analyzed to guide clinical practice.