Detecting Synovitis in Rheumatoid Arthritis

In a comparison of the concordance among ultrasound, clinical assessment, and patient-reported assessment of joint synovitis in patients with rheumatoid arthritis, joint swelling had the highest concordance with ultrasound findings, followed by reported joint symptoms and joint tenderness on physical examination.

Patient-reported joint symptoms appear to be superior to physician examination for joint tenderness in rheumatoid arthritis.

Assessing disease activity and having a target to treat patients with rheumatoid arthritis improves outcomes. Ayako Hirata and fellow researchers in Tokyo pointed out that composite measures of disease activity in rheumatoid arthritis often show discordance with actual disease severity in patients.

Studies show that ultrasound and MRI better detect joint inflammation when compared with physical examination and ultrasound can help predict the progression of rheumatoid arthritis during remission.

The authors sought to determine concordance between physician examination, patient reports of joint symptoms, and synovitis as determined by ultrasound examination and presented their findings in a recent Arthritis Care & Research article.

The study

The authors examined 50 patients with rheumatoid arthritis in the retrospective study. Subjects fulfilled the American College of Rheumatology 1987 revised criteria or the European League Against Rheumatism 2010 criteria for rheumatoid arthritis. All subjects underwent physical examination and ultrasound examination of joints and filled out self-evaluation surveys.

The results

• In 50 patients with rheumatoid arthritis, 1492 joints were evaluated. Swelling was observed by patient report in 19.3%, by physician examination of tenderness in 12.2%, and by observed swelling in 14.7%. Ultrasonic evidence of synovitis was found in 21.2% of joints.

• Swelling was most concordant with ultrasound examination. Tenderness to palpation showed the least concordance in patients with rheumatoid arthritis.

• Self-assessment showed better concordance than swelling when the metacarpophalangeal and wrist joints were looked at.

• Patient joint symptoms had the best detection rate concordance with ultrasound findings when compared with swelling alone and tenderness (4.0%, 1.8%, and 0.5%, respectively; P<0.01).

• Patient joint symptoms detected 15.8%, 20.6%, and 17.8% of ultrasound confirmed synovitis in patients with rheumatoid arthritis in remission or with low, moderate, and high disease activity scores in 28 joints, respectively.

• Joint swelling detected 26.3%, 11.2%, and 5.2% of ultrasound confirmed synovitis in low, moderate, and high disease activity score in 28 joints, respectively.

• Joint tenderness detected 0.0%, 3.7%, and 1.6 % of ultrasound confirmed synovitis in low, moderate, and high disease activity score in 28 joints, respectively.

• Good correlation was found between physician scoring using the disease activity score in 28 joints and predictions based on the patient-reported count for pain or considerable stiffness in 28 self-evaluated joints (r2=0.82; P<0.0001) and ultrasound evidence of synovitis (r2=0.80; P<0.0001).

Implications for physicians

• Joint swelling in patients with rheumatoid arthritis has the best concordance with ultrasound diagnosis of synovitis, followed by patient self-reporting.

• Joint tenderness on physical examination is unreliable and may lead to a significant number of missed synovitis diagnoses.

• When the total prevalence of ultrasound-confirmed synovitis (21.2% of examined joints) is considered, a large number of joints with inflammation are likely missed-inflamed joints detected only on the basis of symptoms, tenderness, or swelling were 18.6%, 2.2%, and 8.5%, respectively, of joints with signs of synovitis on ultrasonography.

• Examination by a physician alone clearly is inadequate to screen for synovitis in patients with rheumatoid arthritis.

• Using joint ultrasound combined with composite measures, such as the disease activity score in 28 joints criteria, gives clinicians the best chance to make a diagnosis in a majority of synovitis cases.

Disclosures:

The Japan Society for the Promotion of Science provided funding for this study.

References:

Hirata A, Ogura T, Hayashi N, et al. “Concordance of Patient-Reported Joint Symptoms, Physician-Examined Arthritic Signs, and Ultrasound-Detected Synovitis in Rheumatoid Arthritis.” Arthritis Care Res (Hoboken). 2017;69:801-806. doi: 10.1002/acr.23006. Epub 2017 May 8.