Use Ultrasound to Rule Out Arthritis

Ultrasonographic imaging of patients who present with arthralgia may be useful for identifying which are not likely to go on to have inflammatory arthritis, a new study shows.

In patients with a diagnosis of rheumatoid arthritis, early initiation of effective disease-modifying antirheumatic drugs (DMARDs) can slow disease progression and diminish joint damage, the authors noted. Therefore, starting DMARDs in the arthralgia phase, or even sooner, could lead to better patient outcomes.

Up until now, identifying which patients with arthralgia might benefit from such early initiation of DMARD therapy has been fairly difficult. But recent technical developments in MRI and ultrasound suggest that earlier detection of inflammation should be possible.

MRI has the disadvantages of being time-consuming, costly, and not accessible for everyone (such as those who have joint replacements or pacemakers). Although ultrasound is more operator-dependent, this modality is also more flexible and easily applied in the clinic setting.

Led by Myrthe van der Ven of the University Medical Centre Rotterdam, The Netherlands, researchers aimed to determine in which patients with arthralgia clinically apparent inflammatory arthritis would develop within 1 year, using ultrasound to detect subclinical synovitis at their first consultation. They reported their findings in Arthritis Research & Therapy.

The study

This was a multicenter prospective cohort study in which 159 patients with inflammatory joint complaints of the hands, feet, or shoulders that could not be explained by other conditions were monitored for 1 year.

Patients had to have at least 2 painful joints and 2 of the following criteria adapted from the Rotterdam Early Arthritis Cohort (REACH) trial: morning stiffness for more than 1 hour, inability to clench a fist in the morning, pain when shaking someone’s hand, pins and needles in the fingers, difficulties wearing rings or shoes, a family history of rheumatoid arthritis, and unexplained fatigue for less than a year.

Trained examiners blinded to the participants’ clinical details performed ultrasound following European League Against Rheumatism guidelines; 26 joints were evaluated using greyscale and power Doppler imaging. Incident inflammatory arthritis at 1 year, defined as clinical soft tissue swelling, was confirmed as arthritis by the treating rheumatologist, who was unaware of the ultrasound findings.

The findings

Following are some of the findings:

• Within 1 year of follow-up, inflammatory arthritis had developed in 31 (16%) patients, of whom 59% showed ultrasound synovitis at baseline.

• Ultrasound did not perform well in ruling in inflammatory arthritis, with a positive predictive value of only 26%.

• Ultrasound did perform well in ruling out inflammatory arthritis in patients who did not have ultrasound synovitis, with a negative predictive value of 89%.

• Positive power Doppler signal, morning stiffness, and age were independently associated with the development of inflammatory arthritis after 1 year.

Implications for physicians

Although ultrasound is operator-dependent, this imaging technique has been shown to be able to detect synovitis before its clinical appearance. “Given the high [negative predictive value], US has added value to identify which patients would not develop into IA,” the researchers concluded.

They recommend further research to confirm results regarding the diagnostic value of ultrasound synovitis to predict the progression to inflammatory arthritis in patients with early arthralgia.

Disclosures:

This study was financially funded by an investigator-initiated grant from Pfizer.

References:

van der Ven M, van der Veer-Meerkerk M, Ten Cate DF, et al. “Absence of ultrasound inflammation in patients presenting with arthralgia rules out the development of arthritis.” Arthritis Res Ther. 2017 Sep 15;19(1):202. doi: 10.1186/s13075-017-1405-y.