In the largest longitudinal dataset on magnetic resonance imaging (MRI)-detected erosions in hand and foot joints in patients with undifferentiated arthritis to date, findings suggest that assessment of MRI-detected erosions in these patients is not relevant for the early diagnosis of rheumatoid arthritis (RA). Results of the current analysis were published in the Annals of the Rheumatic Diseases.1
Radiographic erosions are a hallmark of RA, but the sensitivity of radiography for the detection of erosions early in the course of disease is low. The European League Against Rheumatism recommends the use of other imaging techniques, such as MRI, because they are more sensitive than radiography for the detection of erosions in these individuals.2
In a previous study, investigators sought to compare erosions in the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joints to determine the specificity of MRI-detected erosions. Erosions in MCP and MTP joints in patients with RA were compared with joints of symptom-free individuals and of those with arthritides other than RA.3 Because MRI-detected erosions were observed in all groups, the specificity of their presence was low.
A few features were identified as being specific to RA, including severe erosions (grade ≥2 based on the RA MRI Scoring System, defined as >10% of bone eroded), erosions in MTP5, and erosions in MTP1 in individuals younger than 40 years.
In the current analysis, the researchers continued their evaluation with the use of a larger longitudinal study to examine the predictive accuracy of MRI-detected erosions more thoroughly. They also conducted a cross-sectional comparison between patients with early RA and those with other arthritides to search for erosion characteristics of wrist joints that are specific to RA.
Wrist erosions that were specific to RA were evaluated by comparing MRI-detected erosions in the wrist of 238 individuals with RA with those of 351 individuals with other arthritides who were enrolled between 2010 and 2014. The number, location, and severity of erosions, along with concomitant bone marrow edema were explored. Subsequently, the predictive value of MRI-detected erosions in MCP, wrist, and MTP joints in 286 patients with undifferentiated arthritis who were studied between 2010 and 2016 were assessed. The predictive accuracy of the presence of any MRI-detected erosions and the presence of RA-specific erosions were evaluated.3
Overall, no RA-specific features of MRI-detected erosions located in the wrist were observed. When the predictive value of MRI-detected erosions was assessed in patients with undifferentiated arthritis, any MRI-detected MCP and MTP erosions were found in 49% of the 286 patients with undifferentiated arthritis and did not predict the development of RA in these individuals (odds ratio [OR], 1.2; 95% CI, 0.8-2.0; positive predictive value [PPV], 48%). RA-specific erosions, which were found in only 7% of patients with undifferentiated arthritis, were not associated with the development of RA (OR, 0.6; 95% CI, 0.2-1.5; PPV, 33%). Moreover, any MRI-detected wrist erosions were present in 61% of individuals with undifferentiated arthritis and were also not predictive of RA development (OR, 1.5; 95% CI, 0.9-2.4; PPV, 49%).
The investigators concluded that although the use of MRI is sensitive for detecting the presence of erosions, the current data imply that assessment of MRI-detected erosions in individuals with undifferentiated arthritis is not useful for the early detection of RA.
- Boeters DM, Boer AC, van der Helm-van Mil AHM. http:Evaluation of the predictive accuracy of MRI-detected erosions in hand and foot joints in patients with undifferentiated arthritis [published online July 31, 2018]. Ann Rheum Dis. doi: 10.1136/annrheumdis-2018-213851
- Colebatch AN, Edwards CJ, Østergaard M, et al. EULAR recommendations for the use of imaging of the joints in the clinical management of rheumatoid arthritis. Ann Rheum Dis. 2013;72(6):804-814.
- Boeters DM, Nieuwenhuis WP, van Steenbergen HW, Reijnierse M, Landewé RBM, van der Helm-van Mil AHM. Are MRI-detected erosions specific for RA? A large explorative cross-sectional study. Ann Rheum Dis. 2018;77(6):861-868.