Ultrasound Features across Subtypes of Juvenile Idiopathic Arthritis

Abstract

Objective: The aim of this study was to evaluate musculoskeletal ultrasound (MSUS) features across categories of juvenile idiopathic arthritis (JIA). Methods: In this cross-sectional study, all patients were subjected to full history taking, clinical examination including disease assessment parameters and laboratory investigations. In addition, all children were examined by both grayscale (GS) and power Doppler (PD) MSUS images. Results: By MSUS, the number of joints with synovial effusion was 697 of a total 2400 examined joints (29%) and joints with synovial thickening counted 673 (28%). The number of joints with positive PD signals was 446 (18.6%). There was a significant difference among JIA subtypes as regards different MSUS features. Moreover, there was a discrepancy regarding synovial effusion (p = 0.018), hypertrophy scores (p = 0.013), and the total US severity score (p = 0.026). This divergence was attributed to the significant difference between systemic juvenile idiopathic arthritis (SJIA) and other categories. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of MSUS in JIA and its subtypes were calculated. Conclusion: MSUS is a highly sensitive method for detecting synovitis, tenosynovitis, and erosive bone disease, and it helps to make proper therapeutic decisions. There was a significant difference among JIA subtypes regarding MSUS features.