Diagnostic test accuracy of magnetic resonance imaging and ultrasound for detecting bone erosion in patients with rheumatoid arthritis

Diagnostic values of different musculoskeletal ultrasound signs, serum uric acid, and their combined detection for gouty arthritis

Objectives

The study aimed to investigate the diagnostic values of different musculoskeletal ultrasound (MSUS) signs, serum uric acid (SUA), and their combined detection for gouty arthritis (GA).

Patients and methods

In this retrospective study, 70 patients (62 males, 8 females; mean age: 46.1±14.1 years; range, 25 to 86 years) diagnosed with GA (the GA group) between August 2022 and March 2023 and 70 patients (54 females, 16 males; mean age: 49.0±14.1 years; range, 21 to 75 years) diagnosed with rheumatoid arthritis and osteoarthritis during the same period (the non-GA group) were included. The positive rate of MSUS signs and SUA in both groups was recorded to compare the differences. The correlations of MSUS signs and SUA with GA were analyzed using Spearman's rank correlation analysis. The diagnostic values of different MSUS signs, SUA, and their combined detection for GA were analyzed using a receiver operating characteristic, the area under the curve (AUC), sensitivity, specificity, and the Youden index.

Results

The positive rate of the double contour (DC) sign (chi-squared [χ2 ]=102.935, p<0.001), hyperechoic spots (χ2=56.395, p<0.001), bone erosions (χ2 =10.080, p<0.001), and SUA (χ2 =41.117, p <0.001) were higher in the GA group than in the non-GA group. The positive rate of the DC sign (rs=0.829, p=0.001), hyperechoic spots (rs=0.631, p<0.001), bone erosion (rs=0.268, p=0.001), and SUA (rs=0.542, p<0.001) were positively correlated with GA. Among the single-indicator measures, the DC sign exhibited the highest diagnostic value (AUC=0.907, sensitivity=81.4%, specificity=100%, p<0.001). Among the combined-indicator measures, the DC sign combined with SUA exhibited the highest diagnostic value (AUC=0.929, sensitivity=91.4%, specificity=94.3%, p<0.001), higher than DC sign detection alone.

Conclusion

The DC sign combined with SUA yielded a high diagnostic value and can thus provide a reliable basis for effectively and efficiently diagnosing GA.

Clinical characteristics and risk factors associated with bone erosion in patients with tophi

INTRODUCTION

If a large amount of urate crystals is deposited in a joint cavity for an extended period of time, bone erosion will occur and gradually cause skeletal muscle necrosis and joint deformity. The aim of this study was to describe the clinical characteristics and factors associated with bone erosion in gout patients with tophi.

METHODS

A total of 210 gout patients with tophi were enrolled and divided into a bone erosion group (n = 135) and a non-bone erosion group (n = 75). Digital radiography (DR) was performed to detect bone erosion in the elbow, wrist, knee, ankle joints, interphalangeal and metatarsophalangeal joints. The clinical characteristics were recorded and compared between the two groups. Multivariate logistic regression analysis was conducted to explore the factors associated with bone erosion.

RESULTS

Compared with the non-bone erosion group, the bone erosion group had an older age, longer disease duration of gout and tophi, higher level of serum creatinine (sCr), higher proportion of drinking history and ulceration, and a lower glomerular filtration rate (GFR). Univariate logistic regression analysis results showed that sex, age, body mass index (BMI), gout duration, tophi duration, GFR, white blood cell (WBC) count, sCr level, smoking history, drinking history, and presence of ulceration were associated with bone destruction. Multivariable logistic regression analysis results indicated that tophi duration, drinking history, ulceration and sCr were positively and independently related to bone erosion.

CONCLUSIONS

Tophi patients with bone erosion presented different clinical characteristics. Tophi duration, drinking history, ulceration and sCr were associated with bone erosion in gout patients with tophi.

Ultrasonography of Shoulder in Rheumatoid Arthritis: A Reliability Exercise Using Consensual Definitions among Maghrebian Rheumatologists

The shoulder may be affected in a large portion of patients with rheumatoid arthritis (RA) worldwide. However, this joint does not receive the attention required during follow-up. Indeed, although numerous clinical tests for diagnosis of a painful shoulder are available, differentiating articular from peri-articular lesions may be difficult in daily practice. Fortunately, the precise diagnosis of shoulder pain in RA has benefited from a reliable imaging modality used to detect its exact origin-ultrasonography (US). This study was aimed at assessing the intra- and inter-observer reliability of ultrasonographic findings for patients with established RA with shoulder pain in a patient-based exercise as a clinical challenge among Maghrebian rheumatologist experts in US. A total of 7 operators examined 10 patients in two rounds independently and blindly of each other. Before beginning the session, all of the rheumatologists reached a consensus on sites and US settings by performing a brief exercise on a normal shoulder. Outcome Measures in Rheumatology Clinical Trials (OMERACT) definitions of US-detected pathologies were used. Each patient underwent US scanning of the painful shoulder in predefined sites based on US technical guidelines of the European Society of Musculoskeletal Radiology: long head of biceps (LHB), subscapularis recess, posterior recess and axillary recess. The presence of subdeltoid or subcoracoid bursitis or full rupture of the suprasupinatus was identified if present. Intra- and inter-observer reliability measures were calculated using the κ coefficient. Intra-observer reliability was good for gray-scale (GS) synovitis in subscapularis and posterior recesses (κ = 0.77 and 0.73, respectively). It was moderate in the presence of GS synovitis and effusion in LHB (κ =0.53 and 0.40, respectively), posterior and subscapularis recess effusion (κ = 0.56 and 0.60, respectively) and GS and power Doppler (PD) synovitis in axillary recesses (κ = 0.58 and 0.49, respectively). Inter-observer reliability was good for PD for LHB signals (κ = 0.78). It was moderate for GS for LHB synovitis (κ = 0.54). Inter-observer agreement was poor for effusion and GS synovitis for subscapularis, posterior and axillary recesses, and very poor for PD signals in these recesses. US was a reliable imaging tool for detecting tenosynovitis in the LHB. However, reliability was moderate to poor in detecting synovitis in subscapularis, posterior and axillary recesses. These findings could be optimized by standardization of sites to assess.

Erosive arthritis in systemic lupus erythematosus: not only Rhupus

Systemic lupus erythematosus (SLE)-related arthritis has been traditionally defined as non-erosive and is therefore considered a minor manifestation requiring a mild treatment. However, the concept of non-erosive arthritis in SLE has been challenged with the advent of sensitive imaging techniques, such as high-resolution ultrasound with power Doppler or magnetic resonance. The application of these new imaging tools has demonstrated that up to 40% of SLE patients with joint involvement can develop erosive damage. Thus, this more aggressive phenotype can be identified not only in patients overlapping with rheumatoid arthritis (RA). This issue has been considered for the first time in the classification criteria proposed by Systemic Lupus International Collaborating Clinics in 2012, in which the old definition of "non-erosive arthritis" was replaced with either synovitis or tenderness in two or more joints with morning stiffness, suggesting the possible presence of an erosive phenotype. Accordingly, the 2019 EULAR/ACR's SLE recommendations advise treatment with immunosuppressant or biological drugs for patients with RA-like moderate arthritis. As a result, several studies have investigated the presence of biomarkers associated with SLE erosive damage. A relevant role seems to be played by the autoantibodies directed against post-translational modified proteins: above all, a significant association has been observed with antibodies directed against citrullinated and carbamylated proteins. Conversely, the rheumatoid factor was not associated with this more aggressive SLE-related arthritis. Nonetheless, some pro-inflammatory factors have been associated with erosive damage in SLE patients. These results suggest new pathogenic mechanisms underlining erosive arthritis, only partially shared with RA. Hence, in the present narrative review, we summarized available data about erosive arthritis in SLE patients, in the light of its impact on therapeutic decisions.