Serum calprotectin (S100A8/A9): a promising biomarker in diagnosis and follow-up in different subgroups of juvenile idiopathic arthritis

Introduction

In the management of juvenile idiopathic arthritis (JIA), there is a lack of diagnostic and prognostic biomarkers. This study assesses the use of serum calprotectin (sCal) as a marker to monitor disease activity, and as a classification and prognosis tool of response to treatment or risk of flares in patients with JIA.

Methods

Eighty-one patients with JIA from the CAP48 multicentric cohort were included in this study, as well as 11 non-paediatric healthy controls. An ELISA method was used to quantify sCal with a commercial kit.

Results

Patients with an active disease compared with healthy controls and with patients with inactive disease showed an eightfold and a twofold increased level of sCal, respectively. sCal was found to be correlated with the C-reactive protein (CRP) and even more strongly with the erythrocyte sedimentation rate. Evolution of DAS28 scores correlated well with evolution of sCal, as opposed to evolution of CRP. With regard to CRP, sCal could differentiate forms with active oligoarthritis from polyarthritis and systemic forms. However, sCal brought an added value compared with the CRP as a prognosis marker. Indeed, patients with active disease and reaching minimal disease activity (according to Juvenile Arthritis Disease Activity Score) at 6 months following the test had higher sCal levels, while patients with inactive disease had higher sCal levels if a flare was observed up to 3–9 months following the test.

Conclusions

This study confirms the potential uses of sCal as a biomarker in the diagnosis and follow-up of JIA.

Treating juvenile idiopathic arthritis to target: what is the optimal target definition to reach all goals?

In 2018, an international Task Force formulated recommendations for treating Juvenile Idiopathic Arthritis (JIA) to target. The Task Force has not yet resolved three issues. The first issue is the lack of a single "best" target. The Task Force decided not to recommend the use of a specific instrument to assess inactive disease or remission. Recent studies underscore the use of a broad target definition. The second issue is the basic assumption that a treatment aggressively aimed at the target will have 'domino effects' on other treatment goals as well. Thus far, this assumption was not confirmed for pain, fatigue and stiffness. The third issue is shared decision-making, and the role of individual patient targets. Nowadays, patients and parents should have a more active role in choosing targets and their personal treatment goals. In our department the electronic medical records have been restructured in such a way that the patient's personal treatment goals with a target date appears on the front page. The visualization of their specific personal goals helps us to have meaningful discussions on the individualized treatment strategy and to share decisions. In conclusion, a joint treat to target (T2T) strategy is a promising approach for JIA. The Task Force formulated valuable overarching principles and a first version of recommendations. However, implementation of T2T needs to capture more than just inactive disease. Patients and parents should have an active role in choosing personal targets as well.

Treatment in juvenile rheumatoid arthritis and new treatment options

Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease of the childhood with the highest risk of disability. Active disease persists in the adulthood in a significant portion of children with juvenile rheumatoid arthritis despite many developments in the diagnosis and treatment. Therefore, initiation of efficient treatment in the early period of the disease may provide faster control of the inflammation and prevention of long-term harms. In recent years, treatment options have also increased in children with juvenile idiopathic arthritis owing to biological medications. All biological medications used in children have been produced to target the etiopathogenesis leading to disease including anti-tumor necrosis factor, anti-interleukin 1 and anti-interleukin 6 drugs. In this review, scientific data about biological medications used in the treatment of rheumatoid arthritis and new treatment options will be discussed.

Prediction of methotrexate efficacy and adverse events in patients with juvenile idiopathic arthritis: a systematic literature review

BACKGROUND

Methotrexate (MTX) is the cornerstone disease-modifying anti-rheumatic drug in juvenile idiopathic arthritis (JIA). In JIA, it is important to start effective treatment early to avoid long-term sequelae, such as joint damage. To accomplish this goal, it is crucial to know beforehand who is going to respond well to MTX. In addition, MTX adverse effects such as MTX intolerance occur frequently, potentially hindering its efficacy. To avoid inefficacy of an otherwise effective drug, the physician should be timely aware of these adverse events. Consequently, to optimise treatment of JIA patients with MTX, predictors for efficacy and adverse events should be used in daily clinical practice. The aim of this study was to summarise the existing knowledge about such predictors.

METHODS

A systematic literature search was performed in PubMed, Embase and The Cochrane Library, and 1,331 articles were identified. These were selected based on their relevance to the topic and critically appraised according to pre-defined criteria. Predictors for MTX efficacy and adverse events were extracted from the literature and tabulated.

RESULTS

Twenty articles were selected. The overall quality of the studies was good. For MTX efficacy, candidate predictors were antinuclear antibody positivity, the childhood health assessment questionnaire score, the myeloid-related protein 8/14 level, long-chain MTX polyglutamates, bilateral wrist involvement and some single nucleotide polymorphisms (SNPs) in the adenosine triphosphate binding cassette and solute carrier transporter gene families. For MTX adverse events, potential predictors were alanine aminotransferase and thrombocyte level and two SNPs in the γ-glutamyl hydrolase and methylenetetrahydrofolate reductase genes. However, validation of most predictors in independent cohorts was still lacking.

CONCLUSIONS

Interesting candidate predictors were found, especially for MTX efficacy. However, most of these were not validated. This should be the goal of future efforts. A clinically relevant way to validate the predictors is by means of creating a clinical prediction model.

[Comparison of the Disease Activity Score-28 and Juvenile Arthritis Disease Activity Score in the juvenile idiopathic arthritis]

INTRODUCTION

the assessment of the activity of rheumatoid arthritis and juvenile idiopathic arthritis is made by means of different tools, respectively DAS-28 and JADAS.

OBJECTIVE

To compare DAS-28 and JADAS with scores of 71, 27 and 10 joint counts in juvenile idiopathic arthritis.

METHOD

A secondary analysis of a phase III placebo-controlled trial, testing safety and efficacy of abatacept was conducted in 8 patients with 178 assessment visits. Joint count scores for active and limited joints, physician's and parents' global assessment by 0-10cm Visual Analog Scale, and erythrocyte sedimentation rate normalized to 0-10 scale, in all visits. The comparison among the activity indices in different observations was made through Anova or adjusted gamma model. The paired observations between DAS-28 and JADAS 71, 27 and 10, respectively, were analyzed by linear regression.

RESULTS

There were significant differences among individual measures, except for ESR, in the first four months of biological treatment, when five of the eight patients reached ACR-Pedi 30, with improvement. The indices of DAS-28, JADAS 71, 27 and 10 also showed significant difference during follow-up. Linear regression adjusted model between DAS-28 and JADAS resulted in mathematical formulas for conversion: [DAS-28=0.0709 (JADAS 71)+1.267] (R(2)=0.49); [DAS-28=0.084 (JADAS 27) +1.7404] (R(2)=0.47) and [DAS-28=0.1129 (JADAS-10) +1.5748] (R(2)=0.50).

CONCLUSION

The conversion of scores of DAS-28 and JADAS 71, 27 and 10 for this mathematical model would allow equivalent application of both in adolescents with arthritis.

Health outcomes of pediatric rheumatic diseases

Measurement of health outcomes in pediatric rheumatic diseases is a critical component of clinical practice and research studies. Measures should include the biological, physical, and psychosocial dimensions of health. Health outcome measures are developed systematically, often using consensus methods. Prior to implementation into practice, health outcome measures must undergo evaluation of measurement properties such as reliability, validity, and responsiveness. There are several health outcome measures available for juvenile idiopathic arthritis, juvenile systemic lupus erythematosus, and juvenile dermatomyositis, many of which are composite measures of disease activity. In addition, tools exist for measuring physical functioning and health-related quality of life. There is increasing focus on the incorporation of patient-reported or parent-reported outcomes when measuring the health state of patients with pediatric rheumatic diseases. Further work is required to determine the optimal health outcome measures and approach for eliciting the patient's perception of their health state in pediatric rheumatology.

Therapeutic advancements in juvenile idiopathic arthritis

The treatment of juvenile idiopathic arthritis (JIA) has substantially evolved over the past two decades. Research has been conducted and is ongoing on how therapies can best be utilized either as monotherapy or in combination for enhanced efficacy. The introduction of biologic therapies that selectively target specific cytokines has changed the acceptable clinical course of childhood arthritis. In addition to the development and utilization of new therapeutic agents, the pediatric rheumatology community has made vital progress toward defining disease activity, developing validated outcome measures, and establishing collaborative networks to assess both clinical outcomes and the long-term side effects related to therapeutics for juvenile arthritis. In this chapter, we will discuss the therapeutic evolution in JIA over the past two decades. Although the largest strides have been made with biologic agents, and these newer drugs have more rigorous data to support their use, select commonly used non-biologic therapies are included, with the discussion focused on more recent updated literature.

A longterm prospective real-life experience with leflunomide in juvenile idiopathic arthritis

OBJECTIVE

To describe a clinical practice with leflunomide (LEF) in juvenile idiopathic arthritis (JIA).

METHODS

Patients with JIA seen between May 2008 and May 2012 and considered nonresponsive to methotrexate (MTX) were given LEF and prospectively followed. Primary outcome was a 28-joint Disease Activity Score (DAS28) of low disease activity (< 3.2) in less than 6 months. Childhood Health Assessment Questionnaire (CHAQ) scores and safety data were recorded.

RESULTS

Forty-three patients (33 female) were included with 25 (58.1%) polyarticular, 10 oligoarticular (7 extended; 3 persistent), 6 systemic, and 2 enthesitis-related. Ten (23.2%) were rheumatoid factor-positive and 7 (16.3%) had antinuclear antibodies. Prior drugs other than MTX: 11 (25.5%) chloroquine diphosphate + MTX and 2 (4.6%) sulfasalazine + MTX; mean prednisone dose was 6.4 ± 9.3 mg. The MTX dose prior to LEF was 14.5 ± 4.5 mg/m(2)/week. LEF dose and duration of therapy were 16.6 ± 5.2 mg/d and 3.6 ± 2.2 years, respectively. Nineteen patients (44.2%) interrupted LEF: 1 entered remission, 11 were nonresponsive, and 7 were intolerant (16.2%). Baseline DAS28 (5.57 ± 0.7) dropped to 3.7 ± 1.2 at final analysis (p < 0.001) and 16 patients (37.2%) had a low DAS28 [< 3.2; 12 (27.9%) while taking LEF + MTX and 4 (9.3%) while taking monotherapy]. At last followup, the number of patients with DAS28 > 5.1 dropped from 34 (79%) to 9 (20.9%) and CHAQ scores from 0.86 ± 0.7 to 0.44 ± 0.5 (p < 0.001).

CONCLUSION

LEF isolated or combined with MTX is effective and safe to treat JIA in patients refractory to MTX.

Validity of a three-variable Juvenile Arthritis Disease Activity Score in children with new-onset juvenile idiopathic arthritis

OBJECTIVES

To investigate the validity and feasibility of the Juvenile Arthritis Disease Activity Score (JADAS) in the routine clinical setting for all juvenile idiopathic arthritis (JIA) disease categories and explore whether exclusion of the erythrocyte sedimentation rate (ESR) from JADAS (the 'JADAS3') influences correlation with single markers of disease activity.

METHODS

JADAS-71, JADAS-27 and JADAS-10 were determined at baseline for an inception cohort of children with JIA in the Childhood Arthritis Prospective Study. JADAS3-71, JADAS3-27 and JADAS3-10 were determined using an identical formula but with exclusion of ESR. Correlation of JADAS with JADAS3 and single measures of disease activity/severity were determined by category.

RESULTS

Of 956 eligible children, sufficient data were available to calculate JADAS-71, JADAS-27 and JADAS-10 at baseline in 352 (37%) and JADAS3 in 551 (58%). The median (IQR) JADAS-71, JADAS-27 and JADAS-10 for all 352 children was 11 (5.9-18), 10.4 (5.7-17) and 11 (5.9-17.3), respectively. Median JADAS and JADAS3 varied significantly with the category (Kruskal-Wallis p=0.0001), with the highest values in children with polyarticular disease patterns. Correlation of JADAS and JADAS3 across all categories was excellent. Correlation of JADAS71 with single markers of disease activity/severity was good to moderate, with some variation across the categories. With the exception of ESR, correlation of JADAS3-71 was similar to correlation of JADAS-71 with the same indices.

CONCLUSIONS

This study is the first to apply JADAS to all categories of JIA in a routine clinical setting in the UK, adding further information about the feasibility and construct validity of JADAS. For the majority of categories, clinical applicability would be improved by exclusion of the ESR.

Disease activity measures in paediatric rheumatic diseases

Disease activity refers to potentially reversible aspects of a disease. Measurement of disease activity in paediatric rheumatic diseases is a critical component of patient care and clinical research. Disease activity measures are developed systematically, often involving consensus methods. To be useful, a disease activity measure must be feasible, valid, and interpretable. There are several challenges in quantifying disease activity in paediatric rheumatology; namely, the conditions are multidimensional, the level of activity must be valuated in the context of treatment being received, there is no gold standard for disease activity, and it is often difficult to incorporate the patient's perspective of their disease activity. To date, core sets of response variables are defined for juvenile idiopathic arthritis, juvenile systemic lupus erythematosus, and juvenile dermatomyositis, as well as definitions for improvement in response to therapy. Several specific absolute disease activity measures also exist for each condition. Further work is required to determine the optimal disease activity measures in paediatric rheumatology.

Recent developments in disease activity indices and outcome measures for juvenile idiopathic arthritis

There has been a concerted and important international effort to develop and validate disease activity and outcome instruments specific to JIA in recent years. This review aims to describe the disease assessment indices important to routine clinical care and integral to the design of outcome studies and clinical trials in JIA. In view of the increasing number of JIA clinical studies and clinical trials, together with a number of national and international paediatric biologic registers, it is important that knowledge of these new outcome measures is widespread, such that results can be placed in a meaningful context.

Defining cut-off values for disease activity states and improvement scores for patient-reported outcomes: the example of the Rheumatoid Arthritis Impact of Disease (RAID)

INTRODUCTION

The Rheumatoid Arthritis Impact of Disease (RAID) is a patient-reported outcome measure evaluating the impact of rheumatoid arthritis (RA) on patient quality of life. It comprises 7 domains that are evaluated as continuous variables from 0 (best) to 10 (worst). The objective was to define and identify cut-off values for disease activity states as well as improvement scores in order to present results at the individual level (for example, patient in acceptable state, improved patient).

METHODS

Patients with definite active RA requiring anti-tumour necrosis factor (anti-TNF) therapy were seen at screening, baseline and after 4 and 12 weeks of etanercept therapy. Answers to "Gold standard" questions on improvement (MCII: Minimum Clinically Important Improvement) and an acceptable status (PASS: Patient Acceptable Symptom State) were collected as well as the RAID score and Disease Activity Score 28- erythrocyte sedimentation rate (DAS28-ESR). Cut-offs were defined by different techniques including empirical, measurement error and gold standard anchors. The external validity of these cut-offs was evaluated using the positive likelihood ratio (LR) based on the patient's perspective (for example, patient's global) and on low disease activity status (such as DAS28-ESR).

RESULTS

Ninety-seven (97) of the 108 recruited patients (age: 54 ± 13 years old, female gender: 75%, rheumatoid factor positive: 81%, disease duration: 8 ± 7 years, CRP: 18 ± 30 mg/l, DAS28-ESR: 5.4 ± 0.8) completed the 12 weeks of the study. The different techniques suggested thresholds ranging from 0.2 to 3 (absolute change) and from 6 to 50% (relative change) for defining MCII and thresholds from less than 1 to less than 4.2 for defining PASS. The evaluation of external validity (LR+) showed the highest LR+ was obtained with thresholds of 3 for absolute change; 50% for relative change and less than 2 for an acceptable status.

CONCLUSIONS

This study showed that thresholds defined for continuous variables are closely related to the methodological technique, justifying a systematic evaluation of their validity. Our results suggested that a change of at least 3 points (absolute) or 50% (relative) in the RAID score should be used to define a MCII and that a maximal value of 2 defines an acceptable status.

TRIAL REGISTRATION

Clinicaltrial.gov: NCT004768053.

CD23(+)/CD21(hi) B-cell translocation and ipsilateral lymph node collapse is associated with asymmetric arthritic flare in TNF-Tg mice

Introduction

Rheumatoid arthritis (RA) is a chronic autoimmune disease with episodic flares in affected joints. However, how arthritic flare occurs only in select joints during a systemic autoimmune disease remains an enigma. To better understand these observations, we developed longitudinal imaging outcomes of synovitis and lymphatic flow in mouse models of RA, and identified that asymmetric knee flare is associated with ipsilateral popliteal lymph node (PLN) collapse and the translocation of CD23⁺/CD21^hi B-cells (B-in) into the paracortical sinus space of the node. In order to understand the relationship between this B-in translocation and lymph drainage from flaring joints, we tested the hypothesis that asymmetric tumor necrosis factor (TNF)-induced knee arthritis is associated with ipsilateral PLN and iliac lymph node (ILN) collapse, B-in translocation, and decreased afferent lymphatic flow.

Methods

TNF transgenic (Tg) mice with asymmetric knee arthritis were identified by contrast-enhanced (CE) magnetic resonance imaging (MRI), and PLN were phenotyped as "expanding" or "collapsed" using LNcap threshold = 30 (Arbitrary Unit (AU)). Inflammatory-erosive arthritis was confirmed by histology. Afferent lymphatic flow to PLN and ILN was quantified by near infrared imaging of injected indocyanine green (NIR-ICG). The B-in population in PLN and ILN was assessed by immunohistochemistry (IHC) and flow cytometry. Linear regression analyses of ipsilateral knee synovial volume and afferent lymphatic flow to PLN and ILN were performed.

Results

Afferent lymph flow to collapsed nodes was significantly lower (P < 0.05) than flow to expanding nodes by NIR-ICG imaging, and this occurred ipsilaterally. While both collapsed and expanding PLN and ILN had a significant increase (P < 0.05) of B-in compared to wild type (WT) and pre-arthritic TNF-Tg nodes, B-in of expanding lymph nodes (LN) resided in follicular areas while B-in of collapsed LN were present within LYVE-1+ lymphatic vessels. A significant correlation (P < 0.002) was noted in afferent lymphatic flow between ipsilateral PLN and ILN during knee synovitis.

Conclusions

Asymmetric knee arthritis in TNF-Tg mice occurs simultaneously with ipsilateral PLN and ILN collapse. This is likely due to translocation of the expanded B-in population to the lumen of the lymphatic vessels, resulting in a dramatic decrease in afferent lymphatic flow. PLN collapse phenotype can serve as a new biomarker of knee flare.