Systemic Arterial Aneurysms in Kawasaki Disease: An Important Evidence Gap.

Non-coronary artery systemic arterial aneurysms (SAAs) are rare and an under-reported sequelae of Kawasaki disease (KD). We hypothesize that practices regarding SAA screening and management vary widely among experts and published literature. A survey was sent to members of the International KD Registry regarding their experiences and practices with SAAs in KD patients. For comparison, a systematic scoping review was conducted using PRISMA methodology, from which 25 reports with 83 patients were included. Results from each were compared. Surveys were completed by 48 (56%) of 86 IKDR investigators; 35 (73%) respondents had > 10 years of experience caring for KD patients. However, 33% of respondents had not cared for a patient with SAA. Features prompting assessment for SAA included demographics, presence and degree of coronary artery (CA) involvement, and clinical features, including prolonged/persistent fever, progressing/persistent elevation of inflammatory markers, and resistance to standard treatment. Features prompting screening were somewhat concordant with the characteristics of patients with SAA identified in the scoping review. From the survey, the initial preferred assessment included computed tomographic angiography (48%), ultrasound (29%), and magnetic resonance imaging (24%). In contrast, assessment of patients with SAA from the scoping review commonly used multiple imaging modalities. SAA often regressed, but associated complications included thrombosis, calcification, stenosis, occlusion, and collateral formation. While SAA is a known but rare complication of acute KD, there remains a gap in evidence regarding which patients are at risk, best practices for screening and management, and outcomes. Prospective cohort studies are needed.