From bench to bedside: Calprotectin (S100A8/S100A9) as a biomarker in rheumatoid arthritis.

S100A9/S100A8 (calprotectin), a member of the S100 protein family, has been shown to play a pivotal role in innate immunity activation. Calprotectin plays a critical role in the pathogenesis of rheumatoid arthritis (RA), as it triggers chemotaxis, phagocyte migration and modulation of neutrophils and macrophages. Higher calprotectin levels have been found in synovial fluid, plasma, and serum from RA patients. Recent studies have demonstrated better correlations between serum or plasma calprotectin and composite inflammatory disease activity indexes than c-reactive protein (CRP) or the erythrocyte sedimentation rate (ESR). Calprotectin serum levels decreased after treatment, independently of the DMARD type or strategy. Calprotectin has shown the strongest correlations with other sensitive techniques to detect inflammation, such as ultrasound. Calprotectin independently predicts radiographic progression. However, its value as a biomarker of treatment response and flare after tapering is unclear. This update reviews the current understanding of calprotectin in RA and discusses possible applications as a biomarker in clinical practice.

Plasma calprotectin as a biomarker of ultrasound synovitis in rheumatoid arthritis patients receiving IL-6 antagonists or JAK inhibitors.

Objectives: To analyse the accuracy of plasma calprotectin in patients with rheumatoid arthritis (RA) receiving monoclonal antibodies against IL-6 receptors (anti-rIL-6) or JAK inhibitors (JAKis) in detecting ultrasound (US) synovitis and compare it with acute phase reactants [high-sensitivity C-reactive protein (hs-CRP) and ESR]. Methods: An observational cross-sectional study of RA patients receiving anti-rIL-6 (tocilizumab or sarilumab) or JAKi, (baricitinib or tofacitinib) was made. Plasma calprotectin for the diagnosis of US synovitis [synovial hypertrophy grade (SH) ⩾ 2 plus power Doppler signal (PD) ⩾ 1] was analysed using receiver operating characteristic curves (ROCs). The performance of ESR and hs-CRP was also studied. The three ROC curves were compared to determine which had the highest discriminatory power. Associations between plasma calprotectin and US scores were made using correlation analysis. Results: Sixty-three RA patients were included. Mean plasma calprotectin levels were significantly higher in patients with US synovitis than in those without (0.89 ± 0.85 vs 0.30 ± 0.12 µg/ml; p = 0.0003). A moderate correlation between calprotectin and all US scores (HS score Rho = 0.479; PD score Rho = 0.492; and global score Rho = 0.495) was found. The discriminatory capacity of plasma calprotectin showed an AUC of 0.795 (95% CI: 0.687-0.904). The AUC of hs-CRP and ESR was 0.721 and 0.564, respectively. hs-CRP serum levels showed a low positive correlation with the three US scores (Rho < 0.40). After analysis according to the drugs administered, the correlation disappeared in patients receiving anti-rIL-6. Conclusion: Plasma calprotectin may be a sensitive biomarker of synovial inflammation in RA patients treated with anti-rIL-6 or JAKi.

Real-World Treatment Patterns and Clinical Outcomes of Baricitinib in Rheumatoid Arthritis Patients in Spain: Results of a Multicenter, Observational Study in Routine Clinical Practice (The ORBIT-RA Study).

INTRODUCTION: Baricitinib is an oral Janus kinase (JAK)1/JAK2 inhibitor approved to treat rheumatoid arthritis (RA). This study aimed to investigate patients' characteristics, prescription patterns, effectiveness, and treatment persistence in patients receiving baricitinib in real-world practice in Spain. METHODS: This retrospective longitudinal cohort study conducted in five rheumatology units included adults with RA initiating baricitinib (Sep-2017-May-19) with at least a 6-month-follow-up. Demographic/clinical characteristics, prescription patterns, and changes in disease activity and pain level were collected until treatment discontinuation/end of follow-up. Treatment persistence was estimated by Kaplan-Meier methods. RESULTS: Data from 182 patients were included (mean (SD)): 83.5% women, 62.2 (12.3) years, body mass index 26.8 (5.1), disease duration 13.2 (10.8) years and Charlson Comorbidity Index score 2.4 (2.0). All patients had received at least one conventional synthetic disease-modifying anti-rheumatic drugs (csDMARD) before starting baricitinib and 78.0% at least one biologic disease-modifying anti-rheumatic drugs (bDMARD). Furthermore, 90.1% started with baricitinib 4 mg/day; 43.4% in monotherapy. One hundred and twelve (61.5%) of patients continued baricitinib at data collection time; mean persistence was 14.1 (0.5) months. Overall treatment persistence was 79.7/64.8/59.1% at 6/12/18 months. Seventy (38.5%) patients discontinued baricitinib during follow-up due to loss of efficacy (68.6%) or adverse events (18.6%). In those patients with available scores at the different observed cut-off points, remission or low disease activity was reported in 71.6 and 76.3% of patients at 6/12 months at any index: Disease Activity Score 28 joints using erythrocyte sedimentation rate (DAS28-ESR) (73.1 and 73.5%), Simplified Disease Activity Index (SDAI) (62.4 and 75.0%), and Clinical Disease Activity Index (CDAI) (66.7 and 78.1%). Good or moderate European League Against Rheumatism (EULAR)-response was noted in 80.0 and 78.2% of patients, respectively. Improvement from baseline in pain (Visual Analog Scale) was 2.5 cm and 3.0 cm at 6/12 months, respectively. CONCLUSIONS: This Spanish cohort of patients treated with baricitinib had a long-standing and refractory disease. Nevertheless, high persistence and improvements in disease activity and pain were found at 6 and 12 months after treatment initiation, independently of the composite disease activity measure used, reinforcing the effectiveness of baricitinib in routine clinical practice.

Palindromic rheumatism: Evidence of four subtypes of palindromic-like arthritis based in either MEFV or rheumatoid factor/ACPA status.

INTRODUCTION: MEFV mutations have been documented in patients with palindromic rheumatism (PR) who do not meet FMF criteria, and RF and ACPA positive RA may start with PR. OBJECTIVE: To analyze the clinical phenotype and disease evolution of patients with intermittent, palindromic-like (PL) arthritis seen in our Arthritis Unit according to the RF, ACPA and MEFV mutation status. METHODS: MEFV genotyping was done in 76 patients with PL arthritis as defined by predominantly short attacks (≤7days) and a relapsing course. Characteristics of arthritic episodes, RF and ACPA positivity, and the colchicine response were retrospectively collected. Patients were stratified and evaluated according to MEFV mutations and/or positive autoantibodies (ACPA and/or RF). RESULTS: Among the patients, 26.3% (20/76) had a MEFV mutation and 23 (30%) were ACPA and/or RF positive. MEFV mutations and/or autoantibody status allowed four PL arthritis patients to be distinguished: group I (MEFV+), with younger age of onset, short duration attacks (<3days), mainly located in the knee, more frequent non-articular manifestations (fever, pericarditis or abdominal pain) and good response to colchicine; group II (autoantibody+) is older than group I, with the same frequency of short attacks, but the most affected joints were the wrists and small joints of hands: 48% met RA classification criteria during follow-up and were taking DMARDs; group III (MEFV- and autoantibody-) was the most frequent (48%) and clinically heterogeneous group; 51% had attacks lasting>3days, and 15 patients developed criteria of immune-mediated inflammatory, autoinflammatory or infectious diseases. Group IV (MEFV+ associated with preexisting immune-inflammatory disease), was associated with very short attacks, like groups I and II, superimposed or coincident with definite immune-inflammatory disease, including seropositive RA, with good response to colchicine. CONCLUSIONS: Patients with PL arthritis can be classified in four groups according to the presence or not of MEFV mutations and ACPA/RF antibodies with a different clinical evolution and therapeutic response.

Baricitinib and the Risk of Incident Interstitial Lung Disease: A Descriptive Clinical Case Report from Clinical Trials.

OBJECTIVES: Interstitial lung disease (ILD) occurs in up to 30% of patients with rheumatoid arthritis (RA), resulting in increased morbidity and death in the absence of proven therapies. The aim of this study is to estimate the number of incident ILD cases reported through development studies with baricitinib in patients with RA. METHODS: Estimates were based on 3770 patients with RA from eight randomized clinical trials (four phase 3, three phase 2, one phase 1b) and one long-term extension study on baricitinib for which ILD was not an exclusion criterion with 12,358 patient-years of exposure (PYE). RESULTS: Twenty-one non-infectious cases of ILD were reported with an exposure-adjusted incidence rate (EAIR) of 0.17 per 100 PYE. Of the 21 cases, six were reported as serious and 15 as non-serious resulting in an incidence rate of 0.05 per 100 PYE and 0.12 per 100 PYE, respectively. There were also 11 cases caused by an infectious agent: seven serious (IR: 0.06 per 100 PYE) and four non-serious cases (IR: 0.03 per 100 PYE). CONCLUSIONS: The findings of this analysis in patients with RA treated with baricitinib are consistent with a low risk to develop non-infectious ILD during baricitinib treatment, similar to that observed with other Janus kinase inhibitors.

Comparable long-term outcomes between DAS28-ESR remission criteria and ACR/EULAR definitions in patients with established rheumatoid arthritis.

OBJECTIVE: To compare long-term clinical, immunological, and radiographic outcomes between five sets of remission criteria (four clinical and one ultrasound (US)-based) in a cohort of RA patients in a clinical care setting. METHODS: RA patients in remission (DAS28-ESR <2.6) were selected. Hand US assessments were made, and serum levels of inflammation/angiogenesis biomarkers were determined at baseline. Changes in baseline treatment and radiographic progression, defined as the variation in the modified Sharp van der Heijde score (mSHS) at 5 years, were analyzed. Five concepts were used to define remission: DAS28-ESR<2.6, SDAI<3.3, CDAI<2.8, Boolean criteria and Power Doppler score (PD)=0. RESULTS: Eighty-seven patients with DAS28-ESR<2.6 were included. One-third fulfilled SDAI (33.3%), CDAI (31%), and Boolean (35.6%) remission criteria, and 25.3% had no PD signal in the US evaluation. 26 patients (29.9%) changed therapy, ranging from 13.6% (PD remission) to 33.3% (CDAI remission) (p=0.11). Serum levels of ANG (p=0.015) and TNFa (p=0.025) were significantly lower in patients with Boolean remission, whereas IL-18 levels were significantly lower in those with PD remission (p=0.049). Patients without PD in the US assessment had significantly-lower mSHS erosion progression (p=0.014) at 5 years. CONCLUSIONS: Patients with established RA in DAS28-ESR remission had comparable clinical and radiographic outcomes in SDAI, CDAI, and Boolean definitions in a clinical care setting. US remission remained the closest to structural damage abrogation. Key Points • This study provides real world data on long-term outcomes of five clinical and imaging remission criteria in rheumatoid arthritis. • DAS28-ESR remission criteria had comparable radiographic progression and clinical prognosis than more stringent criteria in clinical practice. • US-based remission was closest to structural damage abolishment.

A multidisciplinary registry of patients with autoimmune and immune-mediated diseases with symptomatic COVID-19 from a single center.

BACKGROUND AND AIM: There is increasing interest regarding SARS-CoV-2 infection in patients with autoimmune and immune-mediated inflammatory diseases (AI/IMID) with some discrepancies in different cohorts about their risk and outcomes. The aim was to describe a multidisciplinary cohort of patients with AI/IMID and symptomatic SARS-CoV-2 infection in a single tertiary center and analyze sociodemographic, clinical, and therapeutic factors associated with poor outcomes. METHODS: A retrospective observational study was conducted from the 1st of March until May 29th, 2020 in a University tertiary hospital in Barcelona, Spain. Patients with an underlying AI/IMID and symptomatic SARS-CoV-2 infection were identified in our local SARS-CoV-2 infection database. Controls (2:1) were selected from the same database and matched by age and gender. The primary outcome was severe SARS-CoV-2 infection, which was a composite endpoint including admission to the intensive care unit (ICU), need for mechanical ventilation (MV), and/or death. Several covariates including age, sex, and comorbidities among others were combined into a multivariate model having severe SARS-CoV-2 as the dependent variable. Also, a sensitivity analysis was performed evaluating AID and IMID separately. RESULTS: The prevalence of symptomatic SARS-CoV-2 infection in a cohort of AI/IMID patients was 1.3%. Eighty-five patients with AI/IMID and symptomatic SARS-CoV-2 were identified, requiring hospitalization in 58 (68%) cases. A total of 175 patients admitted for SARS-CoV-2 (58 with AI/IMID and 117 matched-controls) were analyzed. In logistic regression analysis, a significant inverse association between AI/IMID group and severe SARS-CoV-2 (OR 0.28; 95% CI 0.12-0.61; p = 0.001), need of MV (OR 0.20; IC 95% 0.05-0.71; p = 0.014), and ICU admission (OR 0.25; IC 95% 0.10-0.62; p = 0.003) was found. CONCLUSIONS: Patients with AI/IMID who require admission for SARS-CoV-2 infection have a lower risk of developing severe disease, including the need to stay in the ICU and MV.

Anti-carbamylated protein antibody isotype pattern differs between palindromic rheumatism and rheumatoid arthritis.

BACKGROUND: A restricted response against citrullinated peptides/proteins, with less isotype usage, has been found in palindromic rheumatism (PR) in comparison with rheumatoid arthritis (RA). We hypothesized that this different antibody response may be observed for other post-translational modified proteins. We compared the prevalence and isotype usage of two specificities of anti-carbamylated peptide/protein antibodies (Anti-CarP) in patients with PR and RA. METHODS: Cross-sectional study including 54 patients with pure PR and 53 patients with RA, matched by sex, age, disease duration and ACPA. Anti-CarP specificities were determined by home-made enzyme-linked immunosorbent assay tests using a synthetic chimeric fibrin/filaggrin homocitrullinated peptide (CFFHP) and fetal calf serum (FCS) homocitrullinated protein as antigens. IgG, IgA and IgM isotypes were measured. RESULTS: Anti-CarP were positive (CFFHP or FCS) in 24% and 64% of patients with PR and RA, respectively (p < 0.005). All Anti-CarP isotype proportions were significantly lower in PR than in RA: Anti-CarP-IgG (24% versus 51%), Anti-CarP-IgA (7% versus 34%) and Anti-CarP-IgM (7% versus 36%). Mean titers of Anti-CarP isotypes were also lower in PR. In Anti-CarP positive patients, the isotype distribution differed between PR and RA: IgG Anti-CarP was used in all PR patients and in 79% of RA patients. By contrast, a significantly lower isotype usage of both IgA (31% versus 53%) and IgM (31% versus 56%) was observed in PR patients. No significant differences in clinical or demographic characteristics were observed according to Anti-CarP status in PR patients, except for a higher prevalence of ACPA and higher mean titers of ACPA and rheumatoid factor in Anti-CarP positive patients. CONCLUSION: Anti-CarP are found in patients with PR but in a lower proportion and with a different isotype usage from in RA, suggesting a distinct B cell response to homocitrullinated antigens in PR.

What Matters Most to Patients and Rheumatologists? A Discrete Choice Experiment in Rheumatoid Arthritis.

INTRODUCTION: To determine patient and rheumatologist preferences for rheumatoid arthritis (RA) treatment attributes in Spain and to evaluate their attitude towards shared decision-making (SDM). METHODS: Observational, descriptive, exploratory and cross-sectional study based on a discrete choice experiment (DCE). To identify the attributes and their levels, a literature review and two focus groups (patients [P] = 5; rheumatologists [R] = 4) were undertaken. Seven attributes with 2-4 levels were presented in eight scenarios. Attribute utility and relative importance (RI) were assessed using a conditional logit model. Patient preferences for SDM were assessed using an ad hoc questionnaire. RESULTS: Ninety rheumatologists [52.2% women; mean years of experience 18.1 (SD: 9.0); seeing an average of 24.4 RA patients/week (SD: 15.3)] and 137 RA patients [mean age: 47.5 years (SD: 10.7); 84.0% women; mean time since diagnosis of RA: 14.2 years (SD: 11.8) and time in treatment: 13.2 years (SD: 11.2), mean HAQ score 1.2 (SD: 0.7)] participated in the study. In terms of RI, rheumatologists and RA patients viewed: time with optimal QoL: R: 23.41%/P: 35.05%; substantial symptom improvement: R: 13.15%/P: 3.62%; time to onset of treatment action: R: 16.24%/P: 13.56%; severe adverse events: R: 10.89%/P: 11.20%; mild adverse events: R: 4.16%/P: 0.91%; mode of administration: R: 25.23%/P: 25.00%; and added cost: R: 6.93%/P: 10.66%. Nearly 73% of RA patients were involved in treatment decision-making to a greater or lesser extent; however, 27.4% did not participate at all. CONCLUSION: Both for rheumatologists and patients, the top three decision-making drivers are time with optimal quality, treatment mode of administration and time to onset of action, although in different ranking order. Patients were willing to be more involved in the treatment decision-making process.

Patient Decision Aid (PDA) for Patients with Rheumatoid Arthritis Reduces Decisional Conflict and Improves Readiness for Treatment Decision Making.

OBJECTIVES: The aim of this study was to develop and assess the effectiveness of a patient decision aid (PDA) to support treatment decision making in Spanish patients with moderate-to-severe rheumatoid arthritis (RA) who fail to achieve the therapeutic goal with the current disease-modifying antirheumatic treatment strategy. METHODS: The PDA was developed in accordance with the International Patient Decision Aids Standards recommendations. A steering group led the project. Three literature reviews and two focus groups were performed to develop the PDA prototype. To check its comprehensibility, acceptability, and feasibility, alpha-testing was performed using the Decision Support Acceptability Scale (DSAS). Beta-testing was conducted to assess preliminary evidence of PDA efficacy using the Decisional Conflict Scale (DCS) before and after PDA use. Readiness was evaluated using the Preparation for Decision Making Scale (PDMS). RESULTS: The PDA included (1) a brief description of RA, (2) treatment information, and (3) a values clarification section. Alpha-testing revealed that most patients considered that the information was presented in a good or excellent way and it could help clarify their values and facilitate treatment decision making. Most rheumatologists agreed that the PDA was easy to understand, to use, and allowed them to reach a shared decision. Beta-testing showed that PDA significantly reduced overall patients' decisional conflict [33.2 (DE: 21.4) vs 24.6 (23.5); p < 0.001] and prepared the patient for decision making [PDMS: 67.5 (21.0)]. CONCLUSIONS: We developed a PDA for Spanish patients with moderate-to-severe RA that reduces patients' decisional conflict and increases their readiness for decision making. The use of this PDA in routine clinical practice may improve the quality of the decision-making process and the quality of the choices made.

Treat-To-Target and Treat-To-Budget in Rheumatoid Arthritis: Measuring the Value of Individual Therapeutic Interventions.

Treat-to-target (T2T) and dose tapering after obtaining the therapeutic objective (called "treat-to-budget"-T2B-in this Commentary) are the two most commonly used therapeutic strategies in rheumatoid arthritis. In theory, both strategies could add value to the healthcare system, although they are focused on different objectives: T2T strategy improves outcomes but increases short-term costs, while the cost savings obtained through T2B are associated with higher relapse rates. The systematic implementation of both strategies must be founded on solid evidence of their effectiveness and efficiency. However, the level of evidence between guidelines and individual studies is inconsistent for both strategies and the number and the quality of cost-effectiveness analyses is scarce. Raising the level of evidence requires a move from generalization to individualization by conducting randomized clinical trials that assess each of the many strategies that fall under the umbrella of the overall T2T and T2B concepts. In addition, such studies should consider the therapeutic goals and impact of the disease from the perspective of individual patients, which is only possible by promoting shared decision-making. FUNDING: Lilly Spain.

Cost-effectiveness analysis of baricitinib versus adalimumab for the treatment of moderate-to-severe rheumatoid arthritis in Spain.

Background: Baricitinib is an oral janus kinase inhibitor for the treatment of rheumatoid arthritis (RA) and is approved in Europe for use in adults with moderately-to-severely active RA and an inadequate response or intolerance to conventional synthetic disease-modifying antirheumatic drug (csDMARD) therapy. To date, no economic evaluations have assessed the cost-effectiveness of baricitinib in the Spanish setting. Objectives: To evaluate the cost-effectiveness of baricitinib versus adalimumab for the treatment of moderately-to-severely active RA in the Spanish setting. Methods: A discrete event simulation model was developed in Microsoft Excel. Costs and outcomes were estimated over a lifetime horizon using the Spanish national payer perspective. The model compared baricitinib 4 mg once daily in combination with methotrexate with adalimumab 40 mg every other week in combination with methotrexate. Effectiveness and physical function were captured using the American College of Rheumatology criteria and the Health Assessment Questionnaire-Disability Index, input values of which were derived from a phase 3, double-blind, placebo- and active-controlled trial (RA-BEAM; funded by Eli Lilly and Incyte; ClinicalTrials.gov number, NCT01710358). Costs are presented in Euros, 2018 values. Results: In the base case analysis, baricitinib was associated with a quality-adjusted life year gain of 0.09 years over a lifetime horizon, at an incremental cost of -€558 versus adalimumab. Results of various scenario analyses and probabilistic sensitivity analysis generally were consistent with the base case analysis. Conclusion: This analysis suggests that baricitinib is a cost-effective treatment option compared to adalimumab for Spanish patients with moderately-to-severely active RA and a previous inadequate response or intolerance to csDMARD therapy.

Calprotectin strongly and independently predicts relapse in rheumatoid arthritis and polyarticular psoriatic arthritis patients treated with tumor necrosis factor inhibitors: a 1-year prospective cohort study.

BACKGROUND: Calprotectin is a biomarker of disease activity in rheumatoid arthritis (RA) and psoriatic arthritis (PsA) and predicts relapse in juvenile idiopathic arthritis. Higher drug trough serum levels are associated with a good response in patients treated with tumor necrosis factor inhibitors (TNFi). Power Doppler ultrasound synovitis is predictive of relapse and structural damage progression in patients in clinical remission. The purpose of this study was to analyze the accuracy of serum calprotectin levels, drug trough serum levels (TSL), and power Doppler (PD) activity as predictors of relapse in RA and PsA patients in remission or with low disease activity receiving TNFi. METHODS: This was a longitudinal, prospective, 1-year single-center study of 103 patients (47 RA, 56 PsA) receiving TNFi in remission or with low disease activity (28-joint Disease Activity Score (DAS28) ≤ 3.2). The predictive value of serum calprotectin, TNFi TSL, and PD were assessed using receiver operating characteristic (ROC) analyses. To illustrate the predictive performance of calprotectin, TNFi TSL, and PD score, Kaplan-Meier curves were constructed from baseline to relapse. Associations between baseline factors and relapse were determined using Cox regression models. Multivariate models were constructed to analyze the effect of covariates and to fully adjust the association between calprotectin, TNFi TSL, and PD score with relapse. A generalized estimating equation model with an identity link for longitudinal continuous outcomes was used to assess the effect of covariates on TNFi TSL. RESULTS: Ninety-five patients completed 1 year of follow-up, of whom 12 experienced a relapse. At baseline, relapsers had higher calprotectin levels, lower TNFi TSL, and higher PD activity than nonrelapsers. ROC analysis showed calprotectin fully predicted relapse (area under the curve (AUC) = 1.00). TNFi TSL and PD had an AUC of 0.790 (95% confidence interval (CI) 0.691-0.889) and 0.877 (95% CI 0.772-0.981), respectively. Survival analyses and log rank tests showed significant differences between groups according to calprotectin serum levels (p < 0.001), TNFi TSL (p = 0.004), and PD score (p < 0.001). Univariate Cox regression models showed that time-to-remission/low disease activity (hazard ratio (HR) = 1.17, p < 0.001), calprotectin levels (HR = 2.38, p < 0.001), TNFi TSL (HR = 0.47, p = 0.018), and PD score (HR = 1.31, p < 0.001) were significantly associated with disease relapse. In the multivariate analysis, only baseline calprotectin levels independently predicted disease relapse (HR = 2.41, p = 0.002). The generalized estimating equation analysis showed that only disease activity by DAS28-erythrocyte sedimentation rate (ESR) was significantly associated with longitudinal changes in TNFi TSL (regression coefficient 0.26 (0.0676 to 0.0036), p = 0.001). CONCLUSION: Time-to-remission/low disease activity, calprotectin serum levels, TNFi TSL, and PD score were significantly associated with disease relapse. However, only baseline calprotectin serum levels independently predicted disease relapse in RA and PsA patients under TNFi therapy.

Differing specificities and isotypes of anti-citrullinated peptide/protein antibodies in palindromic rheumatism and rheumatoid arthritis.

BACKGROUND: To analyze differences in the recognition of anti-citrullinated peptide/protein antibody (ACPA) citrullinated epitopes and isotypes in patients with palindromic rheumatism (PR) and rheumatoid arthritis (RA). METHODS: ACPA fine specificities (citrullinated peptides of enolase, fibrin, and vimentin) and isotypes (IgG, IgM, and IgA) were analyzed in 54 patients with longstanding PR and 54 patients with established RA. RESULTS: CCP2 tested positive in 66.7% of patients with PR and RA. The ACPA distribution of fine specificities and isotypes differed between PR and RA patients. PR patients had a lower frequency of fine ACPA specificities than RA patients, which was significant in the case of a peptide derived from vimentin (PR 24.1% vs. 59.3% RA; p < 0.001). The mean number of ACPA specificities was lower in PR than in RA patients, and only 25.9% of PR patients recognized ≥2 additional specificities compared with 46.3% of RA patients. Significantly less isotype usage, especially IgA, was observed in PR patients. CONCLUSION: The ACPA immune response differed in patients with PR and RA, with fewer fine specificities and isotype usage in patients with PR. Some patients with PR may have impaired maturation of the B-cell response against citrullinated peptides with no progression to RA.

Clinical and sonographic biomarkers of structural damage progression in RA patients in clinical remission: A prospective study with 12 months follow-up.

OBJECTIVE: To determine clinical and sonographic biomarkers predicting structural damage progression at 12 months of follow-up as measured by magnetic resonance imaging (MRI) in rheumatoid arthritis (RA) patients in clinical remission. PATIENTS AND METHODS: We included patients with RA in clinical remission, defined as 28-joint disease activity score (DAS28)-erythrocyte sedimentation rate (ESR) <2.6 for >6 months. Ultrasound scans of both hands and knees and MRI of the dominant hand were performed at baseline and at 12 months. RESULTS: Out of 55 patients, 42 completed the follow-up. Among them, 78% were female, aged (median) 54 years; disease duration was 93 months. In total, 12 (28%) patients were taking oral prednisone, 34 (81%) conventional synthetic disease-modifying antirheumatic drugs (csDMARDs), and 20 (47%) biological therapies. At baseline, 45% fulfilled criteria previously defined for ultrasound-defined active synovitis (UdAS) [PD (power Doppler) signal + synovial hyperplasia ≥2]. Multivariate analysis showed significant associations between baseline MRI erosion score, body mass index (BMI), disease duration, prednisone treatment, absence of biologic and csDMARDs, UdAS, and MRI erosion score progression after 12 months. In an exploratory analysis, serum levels of calprotectin correlated significantly with bone edema progression. CONCLUSIONS: We identified clinical and sonographic markers of structural damage progression after 12 months follow-up in patients with RA in clinical remission. Meeting the criteria of ultrasound active synovitis, defined as simultaneous relevant synovial hyperplasia and PD, was associated with erosion progression after 12 months. Calprotectin was associated with bone edema, in an exploratory analysis.

Differing local and systemic inflammatory burden in polyarticular psoriatic arthritis and rheumatoid arthritis patients on anti-TNF treatment in clinical remission.

OBJECTIVES: To analyse clinical, serological and sonographic differences between rheumatoid arthritis (RA) and polyarticular psoriatic arthritis (PsA) patients on anti-TNF therapy in clinical remission. METHODS: Angiogenic and proinflammatory cytokine serum levels were determined by multiplex ELISA in patients with RA and PsA in clinical remission (DAS28-ESR<2.6), clinically-active RA patients (DAS28>3.2) and healthy controls. Ultrasound (US) scans were made of both wrists and hands. RESULTS: 30 RA and 47 PsA patients in remission, 22 active RA patients and 20 healthy controls were included. PsA patients had significantly lower disease activity according to DAS28-ESR (p=0.006) but not according to DAS28-CRP (p=0.319), and lower serum levels of proinflammatory and angiogenic cytokines than RA patients in remission. PsA patients had cytokine levels similar to healthy controls, while RA patients in remission had similar levels to those of active RA patients. Globally, 31 (40.25%) patients in remission had a PD signal and 12 had SH>2 plus PD [1 PsA vs. 11 RA (p=0.0001)], meeting the criteria for ultrasound-defined active synovitis (UdAS). Patients with UdAS had significantly higher levels of IL-6, IL-20, PIGF and SDF1. More PsA patients were on tapered doses of anti-TNF (63.8%), and more frequently as monotherapy (72.3%), compared with RA patients (26.6% and 20%, respectively). CONCLUSIONS: Polyarticular PsA patients in remission had lower levels of local (US synovitis) and systemic inflammation than RA patients in remission, even though a significantly higher percentage of PsA patients were on tapered doses of anti-TNF, mainly in monotherapy.

Calprotectin and TNF trough serum levels identify power Doppler ultrasound synovitis in rheumatoid arthritis and psoriatic arthritis patients in remission or with low disease activity.

BACKGROUND: Serum levels of calprotectin, a major S100 leucocyte protein, are associated with disease activity in rheumatoid arthritis (RA) and psoriatic arthritis (PsA) patients. Higher drug trough serum levels are associated with good response in patients treated with tumour necrosis factor inhibitors (TNFi). Power Doppler ultrasound (PDUS) synovitis is predictive of flare and progression of structural damage in patients in clinical remission. The purpose of this study was to analyse the accuracy of calprotectin and TNFi trough serum levels in detecting PDUS synovitis in RA and PsA patients in clinical remission or with low disease activity who were receiving TNFi. METHODS: We conducted a cross-sectional study of 92 patients (42 with RA, 50 with PsA) receiving adalimumab (ADA), etanercept (ETN) or infliximab who were in remission or had low disease activity (28-joint Disease Activity Score based on erythrocyte sedimentation rate <3.2). Associations of calprotectin, TNFi trough serum levels and acute phase reactants with PDUS synovitis were assessed using correlation and linear regression analyses. The accuracy and discriminatory capacity in detecting PDUS synovitis was assessed using ROC curves. RESULTS: PDUS synovitis was found in 62.4 % of RA patients and 32 % of PsA patients. Both RA and PsA patients with PDUS synovitis had higher calprotectin levels and lower TNFi trough serum levels. Calprotectin positively correlated with ultrasound scores (all r coefficients >0.50 in RA). Calprotectin correlated with the PDUS synovitis score in patients treated with ADA and ETN. Using PDUS synovitis (yes or no) as the reference variable, calprotectin had an AUC of 0.826. The best cut-off was ≥1.66 µg/ml, with a likelihood ratio of 2.77. C-reactive protein (AUC 0.673) and erythrocyte sedimentation rate (AUC 0.731) had a lower discriminatory capacity. TNFi trough serum levels were significantly associated with PDUS synovitis (OR 0.67, 95 % CI 0.52-0.85, p < 0.001) but their accuracy (AUC <0.5) was less than that of calprotectin. TNFi trough serum levels were inversely correlated with calprotectin and PDUS synovitis in RA and PsA patients receiving ADA and ETN. CONCLUSIONS: Calprotectin and TNFi trough serum levels may help identify PDUS synovitis in RA and PsA patients in clinical remission or with low disease activity.