The value of ultrasonography in predicting arthritis in auto-antibody positive arthralgia patients: a prospective cohort study.

INTRODUCTION: Ultrasonography (US) has better sensitivity than clinical evaluation for the detection of synovitis in early rheumatoid arthritis (RA). Patients presenting with arthralgia and a positive anti-citrullinated protein antibodies (ACPA) and/or Rheumatoid Factor (IgM-RF) status are at risk for developing RA. In the present study, US utility and predictive properties in arthralgia patients at risk for the development of arthritis were studied. METHODS: 192 arthralgia patients with ACPA and/or IgM-RF were included. Absence of clinical arthritis was confirmed by two physicians. US was performed by one of two trained radiologists of any painful joint, and of adjacent and contralateral joints. Joint effusion, synovitis and power Doppler (PD) signal in the synovial membrane of the joints and tenosynovitis adjacent to the joint were evaluated and classified on a 4-grade semi-quantitative scale. Grade 2-3 joint effusion, synovitis, tenosynovitis and grade 1-3 Power Doppler signal were classified as abnormal. RESULTS: Forty-five patients (23%) developed arthritis after a mean of 11 months. Inter-observer reliability for synovitis and PD was moderate (kappa 0.46, and 0.56, respectively) and for joint effusion low (kappa 0.23). The prevalence of tenosynovitis was too low to calculate representative kappa values. At joint level, a significant association was found between US abnormalities and arthritis development in that joint for joint effusion, synovitis and PD. At patient level, a trend was seen towards more arthritis development in patients who had US abnormalities for joint effusion, synovitis, PD and tenosynovitis. CONCLUSIONS: US abnormalities were associated with arthritis development at joint level, although this association did not reach statistical significance at patient level. US could potentially be used as a diagnostic tool for subclinical arthritis in seropositive arthralgia patients. However, further research is necessary to improve test characteristics.

Development of a standardized method of assessment of radiographs and radiographic change in juvenile idiopathic arthritis: introduction of the Dijkstra composite score.

OBJECTIVE: To evaluate the sensitivity to change of a newly developed radiologic assessment tool, the Dijkstra score, and to develop a numeric composite score and progressor classification scheme to apply in juvenile idiopathic arthritis (JIA) trials. METHODS: A placebo-controlled trial of sulfasalazine (SSZ) in patients with oligoarticular- and polyarticular-onset JIA yielded the data for this study. Data were obtained from 418 sets of radiographs of the clinically involved and contralateral joints (at study entry and at 6 months' followup) from 66 JIA patients. The Dijkstra score assesses the presence or absence of swelling, osteopenia, joint space narrowing, growth abnormalities, subchondral bone cysts, erosions, and malalignment. These signs were combined in the Dijkstra composite score, to assess inflammation (DI), growth (DG), and damage (DD). Progression was defined as an increase in either the DG or the DD score. Scores were evaluated among all radiographs, a standard set of films (hand, foot, and knee), and per patient. All scores were used to explore differences between the 2 treatment groups. RESULTS: Over time, 58% of joints remained normal, 23% remained abnormal but stable, 14% showed an increase in signs, and 5% showed a decrease in signs. Of the 66 JIA patients, 12% had normal radiographic findings throughout followup, 27% showed abnormalities at some sites without change, and 61% showed change in at least 1 site. Changes in the DI, DG, and DD scores varied considerably per type of joint and occurred most frequently in joints of the standard set. DI and DG scores changed most often in the knees, while DD scores changed primarily in the hands and feet. The disease course in 8% of joints was classified as progressive. Films of SSZ-treated patients, versus the placebo group, showed less deterioration by the DD scores (P = 0.04), and the disease course was more often classified as nonprogressive in the SSZ group (P = 0.037). When progressors were defined as those who had at least one radiograph showing progression, significantly more placebo-treated patients were considered progressors (P = 0.046). CONCLUSION: In this trial data set, the Dijkstra composite score and the resulting progressor classification system are comprehensive and feasible tools that are sensitive to change and discriminate between clinical situations. They should now be tested by other investigators and in other data sets.