Prediction of erosion progression using ultrasound in established rheumatoid arthritis: a 2-year follow-up study

This study aimed to determine whether a range of single-time-point ultrasound (US) measures of synovial disease and serologic characteristics were able to predict progression of US-defined erosive disease in patients with established rheumatoid arthritis (RA). Forty patients were studied prospectively. At baseline, subjective US measures of bone damage and synovial disease, including grayscale and power Doppler (PD) scores pre- and post-Sonovue contrast, were obtained from one proximal inter-phalangeal or metacarpo-phalangeal joint per patient. After a minimum of 2 years, the same joints were scanned to obtain a new US erosion score. Follow-up US erosion scores were obtained in 25 joints. Progressive US determined that bone damage occurred in 12/25 joints, including four of eight treated with anti-tumor necrosis factor therapy. Baseline erosion scores were significantly higher in joints that did not show progressive bone damage in the entire cohort (p = 0.05, n = 25) and a subgroup treated with disease-modifying anti-rheumatic drugs (p = 0.015, n = 17). There were no other significant differences in baseline US or serologic scores between joints that developed progressive damage and those that did not. The majority of single-time-point US measures of synovial disease were not able to identify metacarpo-phalangeal or inter-phalangeal joint destined to develop progressive US-determined bone damage in patients with established RA. This may reflect the use of single-time-point measures, insensitivity of the US erosion score, and the long duration of RA disease in this study.