Musculoskeletal ultrasonic findings in children with Juvenile Idiopathic Arthritis

Introduction: The use of musculoskeletal ultrasonography (MSUS) for patients with Juvenile idiopathic arthritis (JIA) is gaining rising attention in the current clinical practice, being a simple non-invasive tool in diagnosing and assessing JIA patients. We sought to describe MSUS findings in a group of pediatric patients with JIA and correlate these findings to their clinical assessment. Methods: This cross-sectional included 60 JIA patients, aged 1-16 years, 40 were already diagnosed as JIA and on treatment and 20 were newly diagnosed at enrollment in the study They were subjected to clinical assessment and MSUS radiological assessment and were assessed by the 27-joint Juvenile Arthritis Disease Activity Score (JADAS27 score). Results: Oligoarticular was the commonest JIA subtype. Strong agreement was observed between MSUS features and clinical findings (kappa=0.937, P<0.001). Thirty-five cases were diagnosed as oligoarticular JIA, confirmed by MSUS examination at enrollment in 33, while 2 were reclassified as having polyarticular JIA. Also, clinically 22 cases were diagnosed to have polyarticular JIA, 18 of them were confirmed by MSUS examination at enrollment. In addition, significant moderate agreement was observed between the MSUS features and the JADAS27 score (kappa = 0.353, P = 0.003). Conclusions: MSUS is a valuable tool for the diagnosis and follow-up of synovitis in children with JIA.