Ultrasound erosions in the feet best predict progression to inflammatory arthritis in anti-CCP positive at-risk individuals without clinical synovitis

High prevalence of radiographic erosions in early, untreated PsA: results from the SpARRO cohort

AIMS

To investigate the prevalence and distribution of bone erosions in an early psoriatic arthritis (PsA) population using conventional radiography (CR) and to explore the agreement between CR and ultrasound (US) detected bone erosions.

METHODS

Newly diagnosed, treatment naïve PsA patients fulfilling the ClASsification for Psoriatic Arthritis (CASPAR) classification criteria of ≤5 years symptom duration were recruited as part of the Leeds Spondyloarthropathy Register for Research and Observation and underwent CR and US examination of hands and feet.

RESULTS

Overall, 4655 hand and feet joints were assessed in 122 patients. CR erosions were detected in 24.6% (n=30) with lowest prevalence seen below 8 months of symptoms (17.5% vs 24.3%>24 months). The number of erosions was higher on CR (1.55% (63/4,655); US 1.04% (34/3,270)), with 5th metatarsophalangeal (MTP) joint being the most affected site in both CR (5.21% (11/211)) and US (7.14% (15/210)). Erosions in CR were more evenly distributed compared with US where three-quarters of the total number of bone erosions were detected in wrists, second metacarpophalangeal (MCP) and fifth MTP joints. Most joints had almost perfect prevalence-adjusted bias-adjusted kappa values ranging from 0.91 to 1.

CONCLUSIONS

Erosions were seen in a quarter of patients with newly diagnosed, untreated PsA with a declining trend around the 8-month symptom duration cut-off. High levels of agreement between CR and US were seen with CR detecting more erosions. A focused US assessment of the wrist, second MCP and fifth MTP joints may be useful to detect bone erosions in early PsA.

Rheumatoid Arthritis: The Continuum of Disease and Strategies for Prediction, Early Intervention, and Prevention

Rheumatoid arthritis (RA) is known to include a pre-RA stage that can be defined as the presence of familial or genetic risk factors, biomarker abnormalities (eg, anticitrullinated protein antibodies [ACPA]), symptoms, and even abnormal imaging findings prior to the development of the onset of clinical RA with inflammatory arthritis that is apparent on physical examination. Indeed, there are multiple completed or ongoing retrospective case-control as well as prospective observational studies to identify the key biologic drivers of disease. Further, building on the predictive ability of combinations of biomarkers, symptoms, and imaging for future RA, there are multiple clinical trials completed, underway, or in development to identify approaches that may prevent, delay, or ameliorate future clinical RA in at-risk individuals. Importantly, however, although an effective preventive intervention has not yet been identified, at-risk individuals are being increasingly identified in clinical care; this presents a challenge of how to manage these individuals in clinical practice. This review will discuss the current understanding of the biology and natural history of RA development, nomenclature, and current models for prediction of future RA, as well as evaluate the current and ongoing clinical prevention trials with the overall goal to provide insights into the challenges and opportunities in the field of RA prevention. Moreover, this review will provide up-to-date options for clinical management of individuals at risk for RA.

Neutrophils in Inflammatory Bone Diseases

PURPOSE OF REVIEW

In this review, we summarize the current evidence that suggests that neutrophils play a key role in facilitating damage to local bone structures.

RECENT FINDINGS

Neutrophil infiltration is a hallmark of inflammatory bone diseases such as rheumatoid arthritis (RA) and periodontitis disease (PD). Both of these human diseases are marked by an imbalance in bone homeostasis, favoring the degradation of local bone which ultimately leads to erosions. Osteoclasts, a multinucleated resident bone cell, are responsible for facilitating the turnover of bone and the bone damage observed in these diseases. The involvement of neutrophils and neutrophil extracellular trap formation have recently been implicated in exacerbating osteoclast function through direct and indirect mechanisms. We highlight a recent finding that NET proteins such as histones and elastase can generate non-canonical, inflammatory osteoclasts, and this process is mediated by post-translational modifications such as citrullination and carbamylation, both of which act as autoantigens in RA. It appears that NETs, autoantibodies, modified proteins, cytokines, and osteoclasts all ultimately contribute to local and permanent bone damage in RA and PD. However, more studies are needed to fully understand the role of neutrophils in inflammatory bone diseases.

Factors associated with resolution of ultrasound subclinical synovitis in anti-CCP-positive individuals with musculoskeletal symptoms: a UK prospective cohort study

BACKGROUND

Subclinical synovitis occurs in a third of individuals at risk of rheumatoid arthritis. The objective of this study was to assess the reversibility of subclinical synovitis in individuals at risk of rheumatoid arthritis who are positive for anti-cyclic citrullinated peptide (CCP) antibody with musculoskeletal symptoms and investigate factors associated with its resolution within 12 months.

METHODS

We conducted a single-centre, prospective, cohort study in the UK, recruiting individuals aged 18 years or older who were anti-CCP-positive with a new non-specific musculoskeletal symptom but no clinical synovitis. Referrals were made through primary or secondary care. Participants attended a baseline visit, which included a clinical assessment, blood tests, patient questionnaires, and a musculoskeletal ultrasound scan (ie, of wrists and metacarpophalangeal, proximal interphalangeal, and metatarsophalangeal joints), and then follow-up visits every 3 months for the first year, with a repeat ultrasound scan every 12 months. Participants with subclinical synovitis (ie, grey scale ≥1 and power Doppler ≥1) in at least one joint at baseline were selected for this analysis. Investigation of good prognostic factors by 12 months was done first using univariable analysis to identify significant factors in participants with no missing data. Then receiver operating characteristic (ROC) curves were used to establish the optimal cutoffs for significant continuous variables. Finally, a modified Poisson regression approach was performed to identify the best prediction model and was adjusted for confounders, using data from all participants, with missing values imputed. This study is registered with ClinicalTrials.gov, NCT02012764.

FINDINGS

Between June 30, 2008, and Feb 24, 2020, 451 participants consented to participate in the CCP study and 122 (27%) individuals had subclinical synovitis at baseline, of whom 90 (74%) had data available at 12 months. Mean age was 54·1 years (SD 12·5), and 63 (70%) of 90 participants were women and 27 (30%) were men. Subclinical synovitis resolved in 43 (48%) of 90 participants, whereas subclinical synovitis persisted in 47 (52%) participants, 27 (57%) of whom developed clinical synovitis within 12 months. In the multivariable analysis, low anti-CCP titre (relative risk [RR] 1·52, 95% CI 1·04-2·22), negative rheumatoid factor (1·54, 0·92-2·58), subclinical synovitis in only one joint (1·62, 1·04-2·50), and an erythrocyte sedimentation rate of 15 mm/h or lower (1·82, 1·15-2·87) were predictors of subclinical synovitis resolution within 12 months (ie, good prognostic factors). ROC curve showed an area under the curve of 0·84 (95% CI 0·76-0·92; p<0·0001). Resolution occurred in seven (100%) of seven participants with all four factors present, and in only one (7%) of 14 participants with none of the factors present.

INTERPRETATION

In individuals who were anti-CCP-positive, subclinical synovitis disappeared in approximately half of the participants by 12 months and was associated with the presence of good prognostic factors. Subclinical synovitis should be interpreted in the context of these additional factors.

FUNDING

National Institute for Health Research Leeds Biomedical Research Centre.

Predicting Inflammatory Arthritis in At-Risk Persons: Development of Scores for Risk Stratification

BACKGROUND

Inflammatory arthritis (IA) is an immune-related condition defined by the presence of clinical synovitis. Its most common form is rheumatoid arthritis.

OBJECTIVE

To develop scores for predicting IA in at-risk persons using multidimensional biomarkers.

DESIGN

Prospective observational cohort study.

SETTING

Single-center, Leeds, United Kingdom.

PARTICIPANTS

Persons with new musculoskeletal symptoms, a positive test result for anticitrullinated protein antibodies, and no clinical synovitis and followed for 48 weeks or more or until IA occurred.

MEASUREMENTS

A simple score was developed using logistic regression, and a comprehensive score was developed using the least absolute shrinkage and selection operator Cox proportional hazards regression. Internal validation with bootstrapping was estimated, and a decision curve analysis was done.

RESULTS

Of 455 participants, 32.5% (148 of 455) developed IA, and 15.4% (70 of 455) developed it within 1 year. The simple score identified 249 low-risk participants with a false negative rate of 5% (and 206 high-risk participants with a false-positive rate of 72%). The comprehensive score identified 119 high-risk participants with a false-positive rate of 29% (and 336 low-risk participants with a false-negative rate of 19%); 40% of high-risk participants developed IA within 1 year and 71% within 5 years.

LIMITATIONS

External validation is required. Recruitment occurred over 13 years, with lower rates of IA in later years. There was geographic variation in laboratory testing and recruitment availability.

CONCLUSION

The simple score identified persons at low risk for IA who were less likely to need secondary care. The comprehensive score identified high-risk persons who could benefit from risk stratification and preventive measures. Both scores may be useful in clinical care and should also be useful in clinical trials.

PRIMARY FUNDING SOURCE

National Institute for Health and Care Research Leeds Biomedical Research Centre.

The role of ultrasound synovitis scores for patients who are at risk of rheumatoid arthritis

OBJECTIVES

The development of rheumatoid arthritis (RA) has been classified into 6 phases A-F according to the present risk factors in sequence of genes, environments, autoimmunity, arthralgia and joint swelling. To clarify the ultrasound synovitis scores in at-risk patients (phases C-E) and RA (phase F).

METHODS

Patients who had been experiencing hand joint symptoms for at least 6 weeks and asymptomatic patients with positive rheumatoid factor and/or anti-cyclic citrullinated peptide antibodies were enrolled. A 40-joint ultrasonography with semiquantitative synovitis scoring for gray scale (GS) and power Doppler (PD) images was performed.

RESULTS

A total of 139 patients were enrolled and classified into non-RA, phase C, phase D, phase E and phase F. Total GS scores in phases C (17.4 ± 7.0), D (16.0 ± 5.4), E (18.5 ± 7.7) and F (21.8 ± 9.1) were higher than those in non-RA (9.8 ± 4.0, P < 0.001). The total PD score in phase F (3.1 ± 4.6) was higher than that in phases C (0.2 ± 0.5), D (0.1 ± 0.4), and E (0.1 ± 0.3), as well as in non-RA (0.0 ± 0.0, P < 0.01). A total GS score ≥14 differentiated patients at risk for RA from patients with non-RA (area under curve [AUC] 0.82), while a total PD score ≥2 differentiated patients with RA from patients at risk for RA (AUC 0.71).

CONCLUSION

Total GS score may differentiate patients at risk for RA from non-RA patients, while total PD score may differentiate patients with RA from those who are at risk for RA.

High-frequency ultrasound in patients with seronegative rheumatoid arthritis

This study aimed to investigate the value of high-frequency ultrasound (HFUS) in differentiation of the seronegative rheumatoid arthritis (SNRA) and osteoarthritis (OA) and in the diagnosis of SNRA. 83 patients diagnosed with SNRA (SNRA group) and 40 diagnosed with OA (OA group) who received HFUS were retrospectively analyzed. The grayscale (GS) scores, power Doppler (PD) scores, and bone erosion (BE)scores were recorded, and added up to calculate the total scores of US variables. The correlations of the total scores of US variables with the 28-joint disease activity score (DAS28), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were analyzed. The diagnostic efficacy of the total scores of US variables for SNRA was assessed. In the SNRA group, the detection rate of abnormal US findings in the joints and tendons by GS and PD as well as BE was higher than those in the OA group. There were significant differences between the two groups in GS scores and PD scores of joints and tendons, and BE scores of joints (P < 0.05). In the SNRA group, the total scores of most US variables were positively correlated with CRP, ESR, and DAS28 (P < 0.05), while such correlations were not observed in the OA group (P > 0.05). Among different US variables, the diagnostic value of total PD scores of the joints was the highest for SNRA. HFUS could be used to differentiate SNRA from OA and make a diagnosis of SNRA based on joint and tendon synovial sheath assessment.

When and how should we use imaging in individuals at risk of rheumatoid arthritis?

In recent years rheumatologists have begun to shift focus from early rheumatoid arthritis (RA) to studying individuals at risk of developing the disease. It is now possible to use blood, clinical and imaging biomarkers to identify those at risk of progression before the onset of clinical synovitis. The use of imaging, in particular ultrasound (US) and magnetic resonance imaging (MRI), has become much more widespread in individuals at-risk of RA. Numerous studies have demonstrated that imaging can help us understand RA pathogenesis as well as identifying individuals at high risk of progression. In addition, imaging techniques are becoming more sophisticated with newer imaging modalities such as high-resolution peripheral quantitative computed tomography (HR-pQRCT), nuclear imaging and whole body-MRI (WB-MRI) starting to emerge. Imaging studies in at risk individuals are heterogeneous in nature due to the different at-risk populations, imaging modalities and protocols used. This review will explore the available imaging modalities and the rationale for their use in the main populations at risk of RA.

Antibody-induced pain-like behavior and bone erosion: links to subclinical inflammation, osteoclast activity, and acid-sensing ion channel 3-dependent sensitization

ABSTRACT

Several bone conditions, eg, bone cancer, osteoporosis, and rheumatoid arthritis (RA), are associated with a risk of developing persistent pain. Increased osteoclast activity is often the hallmark of these bony pathologies and not only leads to bone remodeling but is also a source of pronociceptive factors that sensitize the bone-innervating nociceptors. Although historically bone loss in RA has been believed to be a consequence of inflammation, both bone erosion and pain can occur years before the symptom onset. Here, we have addressed the disconnection between inflammation, pain, and bone erosion by using a combination of 2 monoclonal antibodies isolated from B cells of patients with RA. We have found that mice injected with B02/B09 monoclonal antibodies (mAbs) developed a long-lasting mechanical hypersensitivity that was accompanied by bone erosion in the absence of joint edema or synovitis. Intriguingly, we have noted a lack of analgesic effect of naproxen and a moderate elevation of few inflammatory factors in the ankle joints suggesting that B02/B09-induced pain-like behavior does not depend on inflammatory processes. By contrast, we found that inhibiting osteoclast activity and acid-sensing ion channel 3 signaling prevented the development of B02/B09-mediated mechanical hypersensitivity. Moreover, we have identified secretory phospholipase A2 and lysophosphatidylcholine 16:0 as critical components of B02/B09-induced pain-like behavior and shown that treatment with a secretory phospholipase A2 inhibitor reversed B02/B09-induced mechanical hypersensitivity and bone erosion. Taken together, our study suggests a potential link between bone erosion and pain in a state of subclinical inflammation and offers a step forward in understanding the mechanisms of bone pain in diseases such as RA.

The value of MRI for detecting subclinical joint inflammation in clinically suspect arthralgia

In the last decade, much research has focused on the development of rheumatoid arthritis (RA) and the symptomatic phase preceding the onset of clinical arthritis. Observational studies on imaging have revealed that subclinical joint inflammation in patients with arthralgia at risk for RA precedes and predicts the onset of clinically apparent arthritis. Moreover, the results of two placebo-controlled randomised proof-of-concept trials in patients with arthralgia and MRI-detected subclinical inflammation studies will soon be available. The initial results are encouraging and suggest a beneficial effect of DMARD treatment on subclinical inflammation. Since this may increase the necessity to detect subclinical joint inflammation in persons with arthralgia that are at risk for RA, we will here review what has been learnt about subclinical inflammation in at-risk individuals by means of imaging. We will focus on MRI as this method has the best sensitivity and reproducibility. We evaluate the prognostic value of MRI-detected subclinical inflammation and assess the lessons learnt from MRIs about the tissues that are inflamed early on and are associated with the clinical phenotype in arthralgia at risk for RA, for example, subclinical tenosynovitis underlying pain and impaired hand function. Finally, because long scan times and the need for intravenous-contrast agent contribute to high costs and limited feasibility of current MRI protocols, we discuss progress that is being made in the field of MRI and that can result in a future-proof way of imaging that is useful for assessment of joint inflammation on a large scale, also in a society with social distancing due to COVID-19 restrictions.

Analysis of Risk Factors for Rheumatoid Arthritis in Yunnan: A Small-Scale Case-Control Study

Objective

To study the risk factors of rheumatoid arthritis (RA) in Yunnan and provide reference for its clinical prevention and treatment.

Methods

From January 2014 to February 2022, a total of 249 RA patients who were admitted to the First People's Hospital of Yunnan Province were selected and 149 healthy people were selected as the controls. The medical records, clinical data of blood test results of anticyclic citrullinated polypeptide (anti-CCP) antibody, antikeratin antibody (AKA), and antiperinuclear factor (APF) were collected. Logistic regression and receiver operating curve (ROC) were used to analyze the correlation between blood anti-CCP antibody, AKA, and APF and the occurrence of RA.

Results

Univariate analysis showed that the age, proportion of hypertension, and diabetes patients in RA patients were significantly different from those in the control group (p < 0.05), but there was no statistical difference in sex (p > 0.05). The area under the curve (AUC) of the serum anti-CCP antibody level in the diagnosis of RA was 0.76 (95% CI: 0.72-0.81, p < 0.01), the sensitivity was 85.23%, the specificity was 61.45%, and the cutoff value was 18.07AU/mL. The positive rates of AKA (33.73%) and APF (43.37%) in the RA patients were significantly higher than those in the controls (4.03% and 6.04%), and the differences were statistically significant (p < 0.001). After adjusting for age, sex, hypertension, and diabetes, logistic regression analysis showed that anti-CCP positivity, AKA positive, and APF positive were all independent risk factors for RA (OR = 20.24, 95% CI: 9.36-43.77, p < 0.01; OR = 4.33, 95% CI: 1.62-11.60, p < 0.01; OR = 5.28, 95% CI: 2.33-11.99, p < 0.01).

Conclusion

Anti-CCP positive, AKA positive, and APF positive are independent risk factors for the occurrence of RA. Serum anti-CCP level has high sensitivity but low specificity in the diagnosis of RA.

Importance of baseline musculoskeletal ultrasound findings in the prognosis of rheumatoid arthritis

OBJECTIVES

To investigate the prognostic value of baseline musculoskeletal ultrasound (MSUS) findings for rheumatoid arthritis (RA).

METHOD

We retrospectively analyzed 138 patients with RA. Patients' first MSUS record was considered as the baseline expression. The subsequent MSUS changes that showed alleviation or progression were regarded as the cutoff point. Grayscale ultrasound (GSUS) synovitis, power Doppler ultrasound (PDUS) synovitis, PDUS tenosynovitis (TS), and bone erosion were scored using a semi-quantitative scale. According to the ultrasound (US) results of the cutoff point, patients were divided into the alleviation group and the progression group. Laboratory results (erythrocyte sedimentation rate [ESR], C-reactive protein [CRP], rheumatoid factor [RF], anticyclic citrullinated peptide [anti-CCP] antibody, and anti-keratin antibody [AKA]), disease activity score in 28 joints (DAS28)-ESR, and US scores were compared between the two groups to analyze the prognostic value of US findings in RA.

RESULTS

The alleviation group had higher levels of CRP, synovitis, TS, GSUS synovitis, PDUS synovitis, PDUS TS, and US total scores at baseline than the progression group (p < 0.05). The alleviation group received more aggressive treatment in their initial approach than the progression group (p < 0.05). The frequency of US examinations in the alleviation group was more than that in the progression group at follow-up (p < 0.05). Presence of baseline synovitis (OR 0.248, p = 0.006) and a higher GSUS synovitis score (OR 0.521, p = 0.006) were negatively correlated with RA progression.

CONCLUSIONS

Presence of baseline synovitis and higher GSUS synovitis score do not always indicate worse prognosis of RA, which can be improved with aggressive treatment. Regular MSUS follow-up may have positive influences on prognosis. Key Points • The presence of synovitis at baseline and higher GSUS synovitis score do not necessarily imply poor prognosis of RA. • Prompt and powerful therapy and regular ultrasound follow-up can slow down the progression of RA and improve its prognosis. • Patients with slight and less arthritis at baseline might be ignored and get worse prognosis due to mild treatment strategies and irregular MSUS examination.

Applying Early Intervention Strategies to Autoimmune Skin Diseases. Is the Window of Opportunity Preclinical? A Dermato-Rheumatology Perspective

Many inflammatory skin diseases exhibit a chronic course with unsatisfactory long-term outcomes. Insights into early intervention approaches in other autoimmune contexts could improve the trajectory of lifelong diseases in terms of sustained remission or minimal disease activity, reduced requirement for therapy and medical resource use, and improved QoL. In both rheumatoid arthritis (RA) and psoriatic arthritis (PsA), we have learned that the timing and intensity of early interventions can influence later outcomes. Investigation into early RA, PsA, and systemic lupus erythematosus has shown that the optimal window of opportunity may even extend into asymptomatic preclinical phases of diseases. Notably, early and preclinical diseases may have pathogenic mechanisms and therapeutic targets that differ from those of the established disease. In this paper, we review the literature on these insights and discuss how similar research and therapeutic strategies may be investigated in cutaneous autoimmunity. We highlight the contribution of skin-resident cells to diseases that were previously thought to be initiated in the primary and secondary lymphoid organs of the immune system. We focus on two dermato‒rheumatology conditions-lupus and psoriasis-which share the commonality that effective early cutaneous disease therapy may have far-reaching implications on abrogating potentially severe systemic disease.

[Agreement between ultrasound-detected inflammation and clinical signs in ankles and feet joints in patients with rheumatoid arthritis]

OBJECTIVE

To investigate the agreement between clinical signs (tenderness and/or swelling) in ankles and feet joints and ultrasound findings in patients with rheumatoid arthritis (RA).

METHODS

RA patients with at least 1 tender and/or swollen joint in bilateral ankles and metatarsophalangeal (MTP) joints detected by physical examination were enrolled and underwent ultrasound examination by greyscale (GS) and power Doppler (PD) mode. The agreement between clinical signs and ultrasound-detected inflammation (joint effusion, synovitis, or tenosynovitis) was analyzed.

RESULTS

In the study, 113 consecutive RA patients were included, with mean age of (52.5±12.6) years, median duration of 60 (13, 129) months, mean disease activity score in 28 joints based on erythrocyte sedimentation rate [DAS28 (ESR)] of 5.1±1.7, mean disease activity score in 28 joints based on C reactive protein[DAS28 (CRP)]of 4.6±1.5. The tenderness and swelling was most commonly detected in ankles (52.7% and 31.9%, respectively), while GS (+) synovitis was most frequently detectable in MTP2 (34.1%), followed by ankles (32.7%) and MTP1 (27.9%), and PD (+) synovitis was most frequently detectable in MTP1 (14.2%), followed by ankles (12.4%) and MTP2 (10.6%). The prevalence of tenosynovitis was 41.1%, which mostly located in tibialis posterior tendon (22.1% of GS positive and 17.6% of PD positive). The highest prevalence of joint effusion was detected in ankles (9.7%), while that of bone erosion in MTP5 (19%). The overall concordance rate between positive clinical signs and ultrasound-determined joint inflammation was poor in the above joints (κ < 0.2, P < 0.05), in which swelling had the highest κ coefficient with ultrasound-determined joint inflammation in ankles (κ=0.225, P < 0.05). Moreover, swelling had the highest κ coefficient with synovitis in ankles (κ=0.231, P < 0.05).The concordance between tenosynovitis and signs in ankles was also poor (κ < 0.20, P < 0.05). There was no significant agreement between joint effusion and clinical signs (P > 0.05).

CONCLUSION

The overall concordance between clinical signs and inflammation on ultrasound was poor in ankles and feet joints. Tenderness and swelling was more common in ankles, while more lesions were detected by ultrasound at MTP joints. Ultrasound is useful in assessing the lesions besides physical examination in patients with RA.

Ultrasound subclinical synovitis in anti-CCP+ at-risk individuals with MSK symptoms: an important and predictable stage in the RA continuum

Objectives

To investigate whether anti-CCP2-positive at-risk individuals with musculoskeletal (MSK) symptoms but without clinical synovitis (CCP2⁺ at-risk) develop US subclinical synovitis before inflammatory arthritis and if US subclinical synovitis can be predicted.

Methods

First, US scans of CCP2⁺ at-risk individuals who developed inflammatory arthritis (‘progressors’) were reviewed for subclinical synovitis prior to inflammatory arthritis development. Patients in whom the pre-progression US scan was negative but the scan was conducted >6 months before progression were excluded. Subsequently, regression analyses were performed to identify predictors of US synovitis in CCP2⁺ at-risk individuals without baseline US abnormalities who had one or more longitudinal US scan and a complete dataset.

Results

US subclinical synovitis was detected in one or more scan in 75 of 97 progressors (77.3%) {median time to inflammatory arthritis development from first evidence of US synovitis 26.5 weeks [interquartile range (IQR) 7–60]}, in whom one or more scan was available, excluding those with a negative scan >6 months from inflammatory arthritis development (n = 38). In 220 CCP2⁺ at-risk individuals with normal baseline US scans, who had one or more longitudinal US scan and a complete dataset, US synovitis was detected in 69/220 (31.4%) [median time to first developing US synovitis 56.4 weeks (IQR 33.0–112.0)]. In the multivariable analysis, only anti-CCP3 antibodies were predictive for the development of US synovitis [odds ratio 4.75 (95% CI 1.97, 11.46); P < 0.01].

Conclusions

In anti-CCP2⁺ at-risk individuals, a stage of subclinical synovitis usually precedes the development of inflammatory arthritis. Anti-CCP2⁺/CCP3⁺ individuals without clinical or US subclinical synovitis may represent the optimal window of opportunity for intervention to prevent joint disease.

During development of rheumatoid arthritis, intermetatarsal bursitis may occur before clinical joint swelling: a large imaging study in patients with clinically suspect arthralgia

Objectives

Intermetatarsal bursitis (IMB) represents juxta-articular synovial inflammation of the intermetatarsal bursae. Recent MRI studies identified IMB as feature of early RA, but whether IMB already occurs in the pre-arthritic phase is unknown. We performed a large MRI study in clinically suspect arthralgia (CSA) to assess the occurrence and prognostic value of IMB.

Methods

A total of 577 consecutive CSA patients underwent contrast-enhanced MRI of the forefoot, metacarpophalangeal joints and wrist. MRIs were evaluated for subclinical synovitis/tenosynovitis/osteitis in line with the RA MRI scoring system (summed as RAMRIS inflammation) and for IMB. IMB was considered present if uncommon in the general population at the same location (i.e. size scored above the 95th percentile in age-matched symptom-free controls). The relation of IMB with other MRI-detected subclinical inflammation (synovitis/tenosynovitis/osteitis) was studied. Cox-regression assessed the association with clinical arthritis development during median 25 months follow-up. ACPA stratification was performed.

Results

At presentation with CSA, 23% had IMB. IMB was more frequent in ACPA-positive than ACPA-negative CSA (47% vs 19%, P < 0.001). Patients with IMB were more likely to also have subclinical synovitis [OR 3.4 (95% CI 1.8, 6.5)] and tenosynovitis [5.9(2.8, 12.6)]. IMB conferred higher risk of developing arthritis [HR 1.6(1.0–2.7) adjusted for other subclinical inflammation]. IMB-presence predicted arthritis development in ACPA-positive CSA [adjusted HR 2.2(1.0–4.7)], but not in ACPA-negative CSA-patients [0.8(0.4–1.7)].

Conclusion

Approximately a quarter of CSA patients have IMB, which is frequently accompanied by subclinical synovitis and tenosynovitis. IMB precedes development of clinical arthritis, particularly in ACPA-positive CSA. These results reinforce the notion that juxta-articular synovial inflammation is involved in the earliest phases of RA development.

Functional disability to evaluate the risk of arthritis in First-degree relatives of Rheumatoid Arthritis patients

OBJECTIVE

The events that occur prior to the onset of rheumatoid arthritis (RA) continue to be delineated. We examined the relationship between self-reported joint symptoms, functional disability, and anticitrullinated protein antibody (ACPA) status in a cohort of first-degree relatives (FDR) of RA patients who are at risk of future disease development.

METHODS

We studied a cohort of 607 FDR of First Nations (FN) RA patients who are at increased risk for future RA development, and analyzed data collected at their enrollment study visit. In parallel, we analyzed data from 279 FN People with no family history of RA. A subset of FDR developed inflammatory arthritis and we analyzed longitudinal data in this group.

RESULTS

The prevalence of joint symptoms and functional disability was higher in FDR compared to non- FDR (all p<0.001). Difficulty walking (37.3% vs 18.0%) and mHAQ were higher in ACPA positive FDR compared to ACPA negative FDR, and mHAQ was independently associated with ACPA seropositivity (OR: 2.79, 1.56-5.00). Longitudinally, in individuals who developed ACPA+ RA, ACPA level and mHAQ score were significantly associated (R = 0.43, p< 0.001) in the preclinical period.

CONCLUSION

Compared to population-based controls, FDR have a high burden of joint symptoms and functional disability. Functional disability was most closely associated with ACPA seropositivity in the FDR, suggesting a direct role for ACPA outside of the context of clinically detectable synovitis. mHAQ appears to be particularly valuable in the assessment of individuals at risk for future RA development.

Should We Be Screening for and Treating Periodontal Disease in Individuals Who Are at Risk of Rheumatoid Arthritis?

There is increasing evidence supporting an association between periodontal disease (PD) and rheumatoid arthritis (RA), both mechanistically and clinically. Trials have shown that treating PD in people with RA may improve RA disease activity. Patients with musculoskeletal symptoms without arthritis, who test positive for cyclic-citrullinated protein antibodies, are at risk of RA (CCP+ at-risk), with seropositivity preceding arthritis onset by months or years. Importantly, there is evidence to suggest that periodontal inflammation may precede joint inflammation in CCP+ at-risk and, therefore, this could be a trigger for RA. There has been increased research interest in RA prevention and the phenotyping of the pre-RA disease phase. This review will examine the merits of identifying individuals who are CCP+ at-risk and performing screening for PD. In addition, we discuss how PD should be treated once identified. Finally, the review will consider future research needed to advance our understanding of this disease association.

Imaging update in inflammatory arthritis

Ultrasonography and magnetic resonance imaging have become important imaging modalities in rheumatological disorders next to standard radiography. Due to their ability to assess both morphological and functional changes they play a significant role in early diagnosis and treatment monitoring. This review presents the latest advancements in imaging of inflammatory arthritis with a focus on two main groups of rheumatic diseases: connective tissue diseases and spondyloarthritis. New developments related to peripheral and sacroiliac joints imaging are discussed, including Superb Micro Flow Imaging and Shear Wave Elastography in ultrasonography, as well as Whole Body MRI, quantitative MRI, and the recent advances in cartilage imaging in MRI, including T2-and T1p-mapping, and dGEMRIC. The role of emerging imaging techniques in the early diagnosis of inflammatory arthritis is discussed, including DECT, VIBE, BoneMRI, and pQCT.

In anti-CCP+ at-risk individuals, radiographic bone erosions are uncommon and are not associated with the development of clinical arthritis

OBJECTIVES

To investigate the prevalence, distribution and predictive value for the development of inflammatory arthritis (IA) of conventional radiography (CR) bone erosions (BE) in anti-CCP positive (CCP+) at-risk individuals with musculoskeletal (MSK) symptoms but without clinical synovitis.

METHODS

Baseline CR of the hands and feet of 418 CCP+ at-risk individuals were analysed. The presence of US-BE was explored in the anatomical areas in which CR-BE were reported. Hands and feet CR at the time of progression were analysed in a subset of individuals who developed IA (73/123, 59.3%). Logistic regression analyses were performed to calculate the predictive value of baseline CR-BE for the development of IA in 394 CCP+ individuals with ≥1 follow-up visit.

RESULTS

BE were detected in 17/418 (4.1%) CCP+ at-risk individuals (median Simple Erosions Narrowing Score-BE = 2.0, IQR: 1.0-2.0; median Sharp van der Heijde score-BE = 4.0, IQR: 3.0-8.5), most frequently in the foot joints (11/17, 64.7% individuals). A total of 123/394 (31.2%) CCP+ at-risk individuals developed IA; 7/17 (41.2%) with, and 116/377 (30.8%) without BE on CR (P = 0.37). US-BE were found in 4/7 (57.1%) individuals with CR-BE who developed IA, but only in 1/10 (10.0%) who did not. At the time of progression, new BE were detected in 4/73 (5.5%) CCP+ individuals on repeated CR. In the regression analyses, baseline CR-BE were not predictive for the development of IA.

CONCLUSIONS

In CCP+ at-risk individuals with MSK symptoms, CR-detected BE are uncommon and do not predict the development of IA.

Towards prevention of autoimmune diseases: The example of rheumatoid arthritis

Prevention is the ultimate aim for clinicians and scientists concerned with severe diseases, like many immune-mediated conditions. Here, we describe recent progress in the understanding of etiology and molecular pathogenesis of rheumatoid arthritis (RA), which make this disease a potential prototype for prevention that may include both public health measures and targeted and personalized approaches that we call "personalized prevention." Critical components of this knowledge are (i) better understanding of the dynamics of the RA-associated autoimmunity that may begin many years before onset of joint inflammation; (ii) insights into how this immunity may be triggered at mucosal surfaces after distinct environmental challenges; (iii) better understanding of which features of the pre-existing immunity may cause symptoms that precede joint inflammation and predict a high risk for imminent arthritis development; and (iv) how molecular events occurring before onset of inflammation might be targeted by existing or future therapies, ultimately by specific targeting of Major histocompatibility complex (MHC) class II restricted and RA-specific immunity. Our main conclusion is that studies and interventions in the phase of autoimmunity preceding RA offer new opportunities to prevent the disease and thereby also understand the molecular pathogenesis of its different variants.

What Is the Value of Ultrasound in Individuals 'At-Risk' of Rheumatoid Arthritis Who Do Not Have Clinical Synovitis?

The identification of biomarkers that help identify individuals at imminent risk of progression to rheumatoid arthritis (RA) is of crucial importance for disease prevention. In recent years, several studies have highlighted the value of musculoskeletal (MSK) ultrasound (US) in predicting progression to inflammatory arthritis (IA) in individuals ‘at-risk’ of RA. These studies have highlighted the following main aspects: first, in RA-related autoantibody-positive individuals, MSK symptoms seem to develop before ‘sub-clinical’ joint inflammation occurs on US. Second, the detection of ‘sub-clinical’ synovitis (and/or bone erosions) greatly increases the risk of IA development in these ‘at-risk’ individuals. US has a potential key role for better understanding the ‘pre-clinical’ stages in individuals ‘at-risk’ of RA, and for the early identification of those individuals at high risk of developing IA. Further research is needed to address questions on image analysis and standardization. In this review, we provide an overview of the most relevant studies which have investigated the value of US in the prediction of RA development in individuals ‘at-risk’ of RA who have MSK symptoms, but no clinical evidence of IA. We highlight recent insights, limitations, and future perspectives of US use in this important population.

Antibodies to Citrullinated Proteins (ACPA) Associate with Markers of Osteoclast Activation and Bone Destruction in the Bone Marrow of Patients with Rheumatoid Arthritis

Normalizing bone metabolism is a challenge in rheumatoid arthritis (RA). Studies in mice suggest that anti-citrullinated protein antibodies (ACPAs) can trigger osteoclast activation and bone resorption in the bone marrow. However, data on the presence and role of ACPAs in human bone marrow are scarce. We investigated whether ACPAs can contribute to osteoclast activation and bone erosion in RA bone marrow. Anti-cyclic citrullinated peptide antibodies (anti-CCP Abs), osteoclast activation indicators–the tartrate-resistant acid phosphatase 5b (TRAP5b) and cathepsin K, and bone degradation marker–C-terminal telopeptide of type I collagen (CTX-I) were measured in the bone marrow and peripheral blood of RA patients using ELISAs. We found that ACPAs present in RA bone marrow was associated with increased amounts of TRAP5b, cathepsin K and CTX-I in this location. Levels of IL-8, the key mediator of anti-citrullinated protein antibody (ACPA)-induced bone resorption, were also elevated in bone marrow containing anti-CCP Abs and positively correlated with TRAP5b and cathepsin K concentrations. Higher levels of TRAP5b, cathepsin K, CTX-I and IL-8 in bone marrow compared to peripheral blood indicate local generation of these molecules. Our results complement data from animal studies and highlight the relevance of ACPAs and bone marrow in bone resorption in RA.

The sonographic identification of cortical bone interruptions in rheumatoid arthritis: a morphological approach

Bone erosions are the hallmark of structural damage in rheumatoid arthritis (RA). Among imaging techniques, ultrasonography (US) has emerged as an accurate, reliable, repeatable, low-cost and non-invasive imaging modality to detect erosive changes in RA. However, small interruptions of the cortical bone detectable by last generation US equipment do not necessarily represent bone erosions. According to the available data, in addition to cortical bone interruption itself, only a few morphological US findings have been proposed to define RA bone erosions. However, other additional features may be considered to facilitate the interpretation of US cortical bone interruptions in RA. These could be summarised using the following four domains: size, site, shape and scenery. This hypothesis article provides a critical literature review of US features characteristic of RA bone erosions and pictorial evidence supporting the potential role of a morphological analysis in the US identification of bone erosions in RA patients.

Plain language summary

The ultrasonographic morphology of cortical interruptions is helpful for the identification of bone erosions in rheumatoid arthritis: the "four Ss" approach Bone erosions are characteristic features of rheumatoid arthritis. They are associated with a more aggressive disease and with irreversible physical disability. In recent years, ultrasonography has emerged as an accurate and reliable technique for the detection of bone erosions, that appear as interruptions of the cortical bone with variable size. However, cortical bone interruptions do not necessarily represent bone erosions. Since bone erosions represent the earliest evidence of the destructive behaviour of RA, their identification is crucial.Besides the cortical interruption itself, only a few morphological ultrasonographic features were proposed to characterise bone erosions in rheumatoid arthritis.We believe that a morphological approach, including size, site, shape and scenery, may be considered to facilitate the interpretation of ultrasonographic cortical bone interruptions in rheumatoid arthritis.In this hypothesis article we carried out a critical review of the scientific literature and provided extensive pictorial evidence of the ultrasonographic spectrum of cortical interruptions supporting the potential role of considering the "four Ss" for the ultrasonographic identification of bone erosions in rheumatoid arthritis.

Structural damage in rheumatoid arthritis assessed by musculoskeletal ultrasound: A systematic literature review by the Structural Joint Damage Task Force of the OMERACT Ultrasound Working Group

OBJECTIVES

To identify and synthesize the evidence for the use and measurement properties of musculoskeletal ultrasound in assessing structural joint damage in patients with rheumatoid arthritis (RA).

METHODS

A systematic literature search (SLR) of the PubMed, Embase and Cochrane Library was performed. Original articles were included published in English reporting on ultrasound of bone erosion, cartilage damage and the measurement properties of ultrasound according to the OMERACT filter 2.1.

RESULTS

Of the 1.495 identified articles 149 were included in the final review, most of which reported on cross-sectional studies and used the OMERACT definitions for ultrasonographic pathology. Among these, bone erosions were assessed in 139 (93.3%), cartilage damage in 24 (16.1%), enthesophytes in 8 (5.4%), osteophytes in 15 (10.1%) and malalignment and ankylosis in a single (0.9%) study, respectively. Most studies (126/149, 84.6%) assessed the joints of the hands. The overwhelming majority of studies (127/149, 85.2%) assessed structural joint damage bilaterally. Validity, reliability and responsiveness were assessed in 21 (14.1%), 34 (22.8%) and 17 (11.4%) studies, respectively.

CONCLUSION

While the results of this SLR suggest that ultrasound is a sensitive, reliable and feasible tool to detect damage in RA, they also highlight the need for further research and validation. Findings of this SLR will inform the next steps of the OMERACT Ultrasound Working Group in developing an ultrasound score for assessing structural joint damage in patients with RA.

The Role of Imaging in Predicting the Development of Rheumatoid Arthritis

Rheumatoid arthritis (RA) remains a chronic debilitating disease with a significant negative societal impact, despite the expanding landscape of treatment options. This condition is often preceded by a phase of systemic autoimmunity with circulating autoantibodies, elevated pro-inflammatory cytokines, or subtle structural changes. The capability of identifying individuals in the preclinical phase of RA disease makes a "preventive window of opportunity" possible. Much recent work has focused on the role of imaging modalities including ultrasound (US), magnetic resonance imaging (MRI), and high-resolution peripheral quantitative computer tomography (HR-pQCT) in identifying at-risk individuals with or without early joint symptoms for the development of inflammatory arthritis. This article will review the evidence and discuss the challenges as well as opportunities of proactive risk assessment by imaging in RA.

The Role of Ultrasound Across the Inflammatory Arthritis Continuum: Focus on "At-Risk" Individuals

In individuals at-risk of developing inflammatory arthritis, the value of an ultrasound (US) scan assessment to predict progression has been demonstrated repeatedly. However, depending on recruitment criteria, these individuals may be at different stages in the arthritis development continuum, therefore representing a heterogeneous population. As a consequence, the predictive value of ultrasound results may differ between cohorts. As other reviews have focused on the challenges in population recruitment or have combined biomarkers predicting value according to one recruitment pathway, we wanted to focus on the sole use of ultrasound assessment and its variation according to population recruitment criteria. In this review, we discuss the use of ultrasound in the different at-risk populations across the inflammatory arthritis disease continuum. This review demonstrates that although some sub-population data is scarce, ultrasound is best predictive in three at-risk populations: those with a positive ACPA test in the context of non-specific MSK symptoms, those with clinically suspect arthralgia and those with palindromic rheumatism. We consider that ultrasound assessment will be a cornerstone in prediction risk modeling and prevention studies of the preclinical phases of IA in the future.

The Role of Musculoskeletal Ultrasound in the Rheumatoid Arthritis Continuum

PURPOSE OF REVIEW

Rheumatoid arthritis (RA) is no longer considered a fixed phenotype but rather a disease continuum. This review outlines the current and potential value of applying ultrasound (US) along this continuum: from the prediction of progression to RA in at-risk individuals, to confirmation of the early diagnosis of RA, as well as the consideration of differential diagnoses, and the use in disease monitoring and defining remission.

RECENT FINDINGS

In individuals at-risk of RA (i.e., positive autoantibodies with symptoms but without synovitis), US has shown a promising predictive value for the development of clinical arthritis, providing the opportunity to improve risk stratification (and disease prevention) of these individuals. The detection of inflammation on US in patients with early undifferentiated arthritis, in which a definite diagnosis cannot be reached, could predict evolution to persistent arthritis, mostly RA. This, in addition to the US potential ability to identify disease specific patterns for different rheumatic conditions, might facilitate early diagnosis and, therefore, improve the management of patients with RA, or other types of inflammatory arthritides. US has also demonstrated the capability to predict radiographic progression, and relapse risk after treatment discontinuation, in RA patients in remission according to the clinical instruments, raising implications in the management, including therapy discontinuation, of these patients. US has an undeniable value in the management of patients at different stages along the RA continuum. Further research is needed to identify which groups of patients benefit the most from US imaging.