Ultrasonography vs. clinical examination in children with suspected arthritis. Does it make sense to use poliarticular ultrasonographic screening?

Objectives: Juvenile idiopathic arthritis (JIA) is a term that encompasses all forms of arthritis that begin before the age of 16 years old, persist for more than 6 weeks and are of unknown cause. The ILAR criteria for JIA classification are based on the number of joints involved. The aim of our study was to compare clinical evaluation and ultrasonography (US) in the assessment of joint synovitis in children with suspected JIA.

Methods: We enrolled in our study all children who presented at our outpatient clinic of Paediatric Rheumatology with suspected JIA. All the children underwent a clinical examination for joint swelling (40 joints), a tender joint count (42 joints) and US examination (42 joints) on the same day. They all returned to the clinic after approximately 2 weeks with the results of the tests prescribed at the first visit and a diagnosis was formulated.

Results: Thirty-one children were enrolled. More synovitis was identified by US than by than clinical examination (42 joints vs. 27). Clinical examination classified as swollen 13 joints that did not result affected at US. Of the 94 painful joints, 24 were affected by synovitis at US. The final diagnoses were: 9 children with JIA (any form), 9 were classified as healthy and 13 with other diseases. One child was reclassified and 2 were diagnosed with JIA thanks to US.

Conclusions: US detected more synovitis than clinical examination in children with suspected JIA, therefore, US should be included in the screening procedure of children with suspected JIA.