Background:
The attentive management of rheumatoid arthritis (RA) has attracted particular attention. US-7 is the first scoring system that combines bone erosions and soft tissue lesions in a single composite scoring system. This study aimed to assess the correlation between US-7 and disease activity score (DAS-28) in clinically active RA patients. We also compared the efficacy of a novel ultrasound score-based system, including nine involved joints (joints assessed with US-7 plus knees) with the standard US-7 score.
Methods:
In this cross-sectional study, all the RA patients referred to the outpatient rheumatology clinic of Qaem Hospital, Mashhad, Iran, from 2019 to 2020 were included. In addition to demographic and socioeconomic information, 28 joints were clinically examined in order to calculate DAS-28. We assessed nine joints comprising the German US-7 and the knees using Grayscale ultrasonography (GSUS) and power Doppler US (PDUS).
Results:
This study composed of thirty-five RA patients (female/male: 33/2) with a mean age of 49.1±12.0 years. The duration of disease and treatment ranged from 0-30 years and 0-20 years. GSUS and PDUS synovitis scores (US-7) were significantly correlated with DAS-28 (P<0.05). GSUS and PDUS synovitis scores (US-7) plus knees (US-9) were also significantly correlated with DAS-28 (r= 0.49 and r=0.45, respectively, P<0.01). The synovitis score measured by GSUS was significantly correlated with GSUS knee synovial score (r=0.42, P=0.01).
Conclusion:
Both US-7 and US-9 synovitis scores were correlated with DAS-28, and the results of US-7 and US-9 were similar. It can be proposed that adding more involved joints into the radiologic assessment does not necessarily lead to better diagnostic value. This point is critical in daily radiologic practice.