Ultrasound versus physical examination in predicting disease flare in children with juvenile idiopathic arthritis: a systematic literature review and qualitative synthesis

In this systematic review we analyzed the published articles related to the predictive value for flare of subclinical synovitis assessed by ultrasound (US) in juvenile idiopathic arthritis (JIA). Medline, Embase and Cochrane databases were searched from 1990 to 2020 by two authors, using PICO methodology. The study is built and reported according to PRISMA guidelines. Searches identified four articles comprising a total of 187 JIA patients in clinical remission from at least 3 months. Two of the articles found US subclinical signs of synovitis to be predictive for flare, with a five times higher risk (with Power Doppler signal as an important feature), while in the other two baseline US abnormalities did not predict a clinical flare. The articles differed for protocols, definitions, and length of follow-up. US has an expanding role in pediatric rheumatology, with interest-ing applications especially during the follow-up, potentially identifying subclinical inflammatory signs predictive of flare. However, the few studies available do not allow definite conclusions at this time.