EULAR-PReS points to consider for the use of imaging in the diagnosis and management of juvenile idiopathic arthritis in clinical practice

Imaging of Juvenile Idiopathic Arthritis

MRI, ultrasound, and conventional radiography each play distinct roles in the evaluation of juvenile idiopathic arthritis (JIA), with MRI being the preferred imaging modality of choice for assessing both inflammatory and destructive changes. These various imaging modalities provide valuable insights into JIA in pediatric patients. However, challenges persist in terms of achieving precision, ensuring validity, and distinguishing between pathologic findings and normal anatomic variations. Establishing normal reference values and implementing scoring systems can aid in the precise evaluation of disease activity and provide information to assist treatment decisions for children with JIA. Ongoing advancements in imaging techniques and standardization initiatives aim to bolster the accuracy of JIA diagnosis and assessment, ultimately leading to enhanced patient care and treatment outcomes.

Does sacroiliitis is a mandatory criterion for enthesitis-related arthritis diagnosis?

INTRODUCTION AND OBJECTIVES

Magnetic resonance imaging (MRI) sensitivity and specificity seem to be less studied in enthesitis-related arthritis (ERA). We aimed to determine the ability of sacroiliac MRI to diagnose ERA patients.

MATERIALS AND METHODS

We conducted a retrospective study including 44 patients with juvenile idiopathic arthritis (JIA). Each patient had a sacroiliac joint MRI. We divided patients into two groups: G1 patients with ERA and G2 patients with non-ERA subtype.

RESULTS

ERA was noted in 61% of the cases. Sacroiliac joints were painful in 15 patients (34%). MRI was normal in 25 patients (57%) (G1:11 versus G2:14) and showed bone marrow edema in the sacroiliac joints in 19 patients (34%) (G1=16 versus G2=3, p=0.005). Sacroiliac joints MRI's sensitivity and specificity in the ERA diagnosis were 61.54% and 82.35%, respectively. Positive and negative predictive values were 84.21% and 58.33%, respectively. Furthermore, sacroiliac joint pain in the clinical examination was able to predict sacroiliac bone edema in MRI with an odds ratio of 6.8 (95% CI 1.68-28.09; p=0.006).

CONCLUSION

Our study showed that sacroiliac joint MRI has good specificity and positive predictive value in the diagnosis of ERA patients among JIA patients. This underlines the usefulness of sacroiliac joint MRI in the early diagnosis of ERA patients.

A clinical perspective on imaging in juvenile idiopathic arthritis

In recent years, imaging has become increasingly important to confirm diagnosis, monitor disease activity, and predict disease course and outcome in children with juvenile idiopathic arthritis (JIA). Over the past few decades, great efforts have been made to improve the quality of diagnostic imaging and to reach a consensus on which methods and scoring systems to use. However, there are still some critical issues, and the diagnosis, course, and management of JIA are closely related to clinical assessment. This review discusses the main indications for conventional radiography (XR), musculoskeletal ultrasound (US), and magnetic resonance imaging (MRI), while trying to maintain a clinical perspective. The diagnostic-therapeutic timing at which one or the other method should be used, depending on the disease/patient phenotype, will be assessed, considering the main advantages and disadvantages of each imaging modality according to the currently available literature. Some brief clinical case scenarios on the most frequently and severely involved joints in JIA are also presented.

Validity of an ultrasonographic joint-specific scoring system in juvenile idiopathic arthritis: a cross-sectional study comparing ultrasound findings of synovitis with whole-body magnetic resonance imaging and clinical assessment

OBJECTIVE

To assess the validity of an ultrasonographic scoring system in juvenile idiopathic arthritis (JIA) by comparing ultrasound detected synovitis with whole-body MRI and clinical assessment of disease activity.

METHODS

In a cross-sectional study, 27 patients with active JIA underwent clinical 71-joints examination, non-contrast enhanced whole-body MRI and ultrasound evaluation of 28 joints (elbow, radiocarpal, midcarpal, metacarpophalangeal 2-3, proximal interphalangeal 2-3, hip, knee, tibiotalar, talonavicular, subtalar and metatarsophalangeal 2-3). One rheumatologist, blinded to clinical findings, performed ultrasound and scored synovitis (B-mode and power Doppler) findings using a semiquantitative joint-specific scoring system for synovitis in JIA. A radiologist scored effusion/synovial thickening on whole-body MRI using a scoring system for whole-body MRI in JIA. At patient level, associations between ultrasound synovitis sum scores, whole-body MRI effusion/synovial thickening sum scores, clinical arthritis sum scores, and the 71-joints Juvenile Arthritis Disease Activity Score (JADAS71) were calculated using Spearman's correlation coefficients (rs). To explore associations at joint level, sensitivity and specificity were calculated for ultrasound using whole-body MRI or clinical joint examination as reference.

RESULTS

Ultrasound synovitis sum scores strongly correlated with whole-body MRI effusion/synovial thickening sum scores (rs=0.74,p<0.01) and the JADAS71 (rs=0.71,p<0.01), and moderately with clinical arthritis sum scores (rs=0.57,p<0.01). Sensitivity/specificity of ultrasound in detecting synovitis were 0.57/0.96 and 0.55/0.96 using whole-body MRI or clinical joint examination as reference, respectively.

CONCLUSION

Our findings suggest that ultrasound is a valid instrument to detect synovitis, and that ultrasound synovitis sum scores can reflect disease activity and may be an outcome measure in JIA.

Developing standards for MRI evaluation of joints in children with juvenile idiopathic arthritis utilizing the temporomandibular joint as a model

The treatment of a patient with juvenile idiopathic arthritis (JIA) is best monitored with standardized and validated tools to measure joint changes over time. Treatment approaches are best indicated if the clinicians are aware of the structural status of the joint at a given time, especially in anatomically deep joints for which clinical assessment is limited. Magnetic resonance imaging (MRI) is of utmost importance for assessment of deep joints and extra-articular soft tissue of the entire body for which ultrasound may be suboptimal. Because the distinction between pathologic and physiologic joint changes on MRI is key for proper diagnosis and treatment of patients with arthropathies, a comprehensive standardized approach is needed to effectively measure outcomes of growing joints of children with JIA. Such an approach is essential for both clinical assessment and to conduct clinical trials in patients with JIA treated in different centers around the world. To meet this need, several international imaging collaborative research groups have been developing MRI scales over the past years, including the MRI in JIA (JAMRI) special interest group within the Outcome Measures in Rheumatology (OMERACT) research network. This manuscript reviews the efforts of the OMERACT JAMRI working group to generate and validate pediatric MRI scoring systems for different joints in children with JIA that can have ubiquitous utilization anywhere in the world. In particular, it describes the different steps of development and validation of an MRI scale using the TMJ as a model.

OMERACT International Consensus for Ultrasound Definitions of Tenosynovitis in Juvenile Idiopathic Arthritis: Systematic Literature Review and Delphi Process

OBJECTIVE

Synovitis and tenosynovitis are present in juvenile idiopathic arthritis (JIA), both as joint pain and/or inflammation, making them difficult to detect on physical examination. Although ultrasonography (US) allows for discrimination of the 2 entities, only definitions and scoring of synovitis in children have been established. This study was undertaken to produce consensus-based US definitions of tenosynovitis in JIA.

METHODS

A systematic literature search was performed. Selection criteria included studies focused on US definition and scoring systems for tenosynovitis in children, as well as US metric properties. Through a 2-step Delphi process, a panel of international US experts developed definitions for tenosynovitis components (step 1) and validated them by testing their applicability on US images of tenosynovitis in several age groups (step 2). A 5-point Likert scale was used to rate the level of agreement.

RESULTS

A total of 14 studies were identified. Most used the US definitions developed for adults to define tenosynovitis in children. Construct validity was reported in 86% of articles using physical examination as a comparator. Few studies reported US reliability and responsiveness in JIA. In step 1, experts reached a strong group agreement (>86%) by applying adult definitions in children after one round. After 4 rounds of step 2, the final definitions were validated on all tendons and at all locations, except for biceps tenosynovitis in children <4 years old.

CONCLUSION

The study shows that the definition of tenosynovitis used in adults is applicable to children with minimal modifications agreed upon through a Delphi process. Further studies are required to confirm our results.

Cell Cultures as a Versatile Tool in the Research and Treatment of Autoimmune Connective Tissue Diseases

Cell cultures are an important part of the research and treatment of autoimmune connective tissue diseases. By culturing the various cell types involved in ACTDs, researchers are able to broaden the knowledge about these diseases that, in the near future, may lead to finding cures. Fibroblast cultures and chondrocyte cultures allow scientists to study the behavior, physiology and intracellular interactions of these cells. This helps in understanding the underlying mechanisms of ACTDs, including inflammation, immune dysregulation and tissue damage. Through the analysis of gene expression patterns, surface proteins and cytokine profiles in peripheral blood mononuclear cell cultures and endothelial cell cultures researchers can identify potential biomarkers that can help in diagnosing, monitoring disease activity and predicting patient's response to treatment. Moreover, cell culturing of mesenchymal stem cells and skin modelling in ACTD research and treatment help to evaluate the effects of potential drugs or therapeutics on specific cell types relevant to the disease. Culturing cells in 3D allows us to assess safety, efficacy and the mechanisms of action, thereby aiding in the screening of potential drug candidates and the development of novel therapies. Nowadays, personalized medicine is increasingly mentioned as a future way of dealing with complex diseases such as ACTD. By culturing cells from individual patients and studying patient-specific cells, researchers can gain insights into the unique characteristics of the patient's disease, identify personalized treatment targets, and develop tailored therapeutic strategies for better outcomes. Cell culturing can help in the evaluation of the effects of these therapies on patient-specific cell populations, as well as in predicting overall treatment response. By analyzing changes in response or behavior of patient-derived cells to a treatment, researchers can assess the response effectiveness to specific therapies, thus enabling more informed treatment decisions. This literature review was created as a form of guidance for researchers and clinicians, and it was written with the use of the NCBI database.

Comparison between ultrasound and magnetic resonance imaging of the temporomandibular joint in juvenile idiopathic arthritis: A systematic review

OBJECTIVES

The objectives of this systematic review were to evaluate the correlation between Ultrasound (US) and Magnetic Resonance Imaging (MRI) in patients with JIA and to investigate the association with Temporomandibular Disorders (TMD).

MATERIALS AND METHODS

The protocol was registered in PROSPERO (CRD42022312734). Databases Medline, Embase, Cochrane Central Register of Controlled Trials, Scopus, Web of Science, Latin American and Caribbean Health Sciences Literature were searched. Eligibility criteria were patients with JIA subjected to diagnostic evaluation using US and MRI. No language restrictions were applied. After duplicate study selection, data extraction and risk of bias assessment according to Cochrane were conducted. Data extraction of patients was conducted by two independent authors.

RESULTS

Five observational studies were included with 217 participants (153 females and 64 males; mean age 11.3 years). The quality of the studies was overall satisfactory. The correlation between US and MRI in children with JIA was 'moderate' in acute arthritis while the chronic arthritis correlated positively in two studies.

CONCLUSIONS

Even if MRI remains the more accurate imaging modality for the detection of TMJ of patients with JIA, US may be useful to early detect pathological conditions and to address the patient with JIA and putative TMJ involvement to a more accurate diagnosis with MRI and consequent appropriate treatment management.

CLINICAL RELEVANCE

MRI should be deemed necessary only secondary to less-invasive assessments with US just to confirm the diagnosis or to increase sensitivity, accuracy of positive predictive values detected.

Structural ultrasound of joints and tendons in healthy children: development of normative data

BACKGROUND

Musculoskeletal ultrasound is a well accessible technique to assess disease activity in children with juvenile idiopathic arthritis. Knowledge of reference values of joint structures is indispensable to differentiate between physiological and pathological finding. The aim of this study was to assess the structural sonographic features of joints and tendons in healthy children from several age groups (0.2-18 year), and develop a set of normative data.

METHODS

Greyscale ultrasound was performed in 500 healthy children (age 0.2-18 years) according to a predefined scanning protocol (Additional file 1) including the shoulder, elbow, wrist, second metacarpophalangeal joint, hip, knee, ankle, and first metatarsophalangeal joint). Demographic data and values of cartilage thickness, tendon diameters, and the degree of capsular distention measured by bone-capsular distance (BCD) were collected. Differences according to the sex were assessed by unpaired t-test. Single and multiple regression analyses were performed between the ultrasound outcomes and covariates such as age, height, weight and body mass index. Growth charts and tables were developed with respect to age. Nonparametric quantile regression was applied using the R-packages quantreg and quantregGrowth.

RESULTS

A total of 195 male and 305 female volunteers were included between the age of 0 and 18 years (mean age 8.9; range: 0.2-17.9 years). Cartilage diminished markedly as children aged, and cartilage of the boys was significantly thicker compared to the girls in all joints (p < 0.001). In addition, cartilage became thinner as children's height and weight increased (beta regression coefficients between - 0.27 and - 0.01, p < 0.0001). Capsular distention (i.e., BCD > 0 mm) was uncommon in the ankle, wrist and MCP2 (resp. in 3, 6, and 3% of cases). It was more common in the suprapatellar and parapatellar knee, MTP1 and posterior recess of the elbow (resp. in 34, 32, 46, and 39% of cases). In the hip, some capsular distention was always present. Age was found to be the best predictor for BCD (beta regression coefficients between 0.05 and 0.13, p < 0.0001). Height was, in addition to age, a good predictor of tendon diameter (beta regression coefficients between 0.03 and 0.14, p < 0.0001). Growth curves and tables for each variable were developed.

CONCLUSIONS

Reference values of sonographic cartilage thickness, BCD and diameters of tendons at several joints were established from 500 healthy children, aged between 0.2 and 18 years. Growth charts and tables were developed to distinguish normal findings from pathology in children with complaints suspicious of arthritis.

Comprehensive and reliable sonographic assessment and scoring system for inflammatory lesions of the paediatric ankle

OBJECTIVE

The clinical decision-making process in paediatric arthritis lacks an objective, reliable bedside imaging tool. The aim of this study was to develop a US scanning protocol and assess the reliability of B-mode and Doppler scoring systems for inflammatory lesions of the paediatric ankle.

METHODS

As part of the Childhood Arthritis and Rheumatology Research Alliance (CARRA) US group, 19 paediatric rheumatologists through a comprehensive literature review developed a set of standardized views and scoring systems to assess inflammatory lesions of the synovial recesses as well as tendons of the paediatric ankle. Three rounds of scoring of still images were followed by one practical exercise. Agreement among raters was assessed using two-way single score intraclass correlation coefficients (ICC).

RESULTS

Of the 37 initially identified views to assess the presence of ankle synovitis and tenosynovitis, nine views were chosen for each B-mode and Doppler mode semi-quantitative evaluation. Several scoring exercises and iterative modifications resulted in a final highly reliable scoring system: anterior tibiotalar joint ICC: 0.93 (95% CI 0.92, 0.94), talonavicular joint ICC: 0.86 (95% CI 0.81, 0.90), subtalar joint ICC: 0.91 (95% CI 0.88, 0.93) and tendons ICC: 0.96 (95% CI 0.95, 0.97).

CONCLUSION

A comprehensive and reliable paediatric ankle US scanning protocol and scoring system for the assessment of synovitis and tenosynovitis were successfully developed. Further validation of this scoring system may allow its use as an outcome measure for both clinical and research applications.

Determination of Relative Weightings for Sacroiliac Joint Pathologies in the OMERACT Juvenile Arthritis Magnetic Resonance Imaging Sacroiliac Joint Score

This study aims to determine the relative weights (point value) of items of the juvenile idiopathic arthritis magnetic resonance imaging-sacroiliac joint scoring system (JAMRIS-SIJ). An adaptive multicriteria decision analysis was performed using the 1000Minds web application to determine the relative weights of the items in the JAMRIS-SIJ inflammation and damage domains. Experts in imaging and rheumatology independently completed a conjoint analysis survey (CAS) to determine the point value of the measurement items of the JAMRIS-SIJ. Each CAS survey question asked the expert to compare two hypothetical patient profiles, which were otherwise similar but different at two items at a time, and to select which item showed a more severe stage of inflammation or osteochondral damage. In addition, experts ranked 14 JAMRIS-SIJ grade only or image + grade patient vignettes while blinded to the CAS-derived weights. The validity of the weighted JAMRIS-SIJ was tested by comparing the expert CAS-weighted score and the image + grade ranking method. Seventeen experts completed the CAS (11 radiologists and 6 rheumatologists). Considering the point value for inflammation domain items, osteitis (24.7%) and bone marrow edema (24.3%) had higher group-averaged percentage weights compared to inflammation in erosion cavity (16.9%), joint space enhancement (13.1%), joint space fluid (9.1%), capsulitis (7.3%), and enthesitis (4.6%). Similarly, concerning the damage domain, ankylosis (41.3%) and erosion (25.1%) showed higher group-averaged weights compared to backfill (13.9%), sclerosis (10.7%), and fat metaplasia lesion (9.1%). The Spearman correlation coefficients of the CAS-weighted vignette order and unweighted JAMRIS-SIJ grade only order vignettes for all experts were 0.79 for inflammation and 0.80 for damage. The correlations of image vignettes among imaging experts to CAS were 0.75 for inflammation and 0.90 for damage. The multicriteria decision analysis identified differences in relative weights among the JAMRIS-SIJ measurement items. The determination of the relative weights provided expert-driven score scaling and face validity for the JAMRIS-SIJ, enabling the future evaluation of its longitudinal construct validity.

The potential role of molecular mimicry by the anaerobic microbiome in the aetiology of autoimmune disease

Autoimmune diseases are thought to develop as a consequence of various environmental and genetic factors, each of which contributes to dysfunctional immune responses and/or a breakdown in immunological tolerance towards native structures. Molecular mimicry by microbial components is among the environmental factors thought to promote a breakdown in immune tolerance, particularly through the presence of cross-reactive epitopes shared with the human host. While resident members of the microbiome are essential promoters of human health through immunomodulation, defence against pathogenic colonisation and conversion of dietary fibre into nutritional resources for host tissues, there may be an underappreciated role of these microbes in the aetiology and/or progression of autoimmune disease. An increasing number of molecular mimics are being identified amongst the anaerobic microbiota which structurally resemble endogenous components and, in some cases, for example the human ubiquitin mimic of Bacteroides fragilis and DNA methyltransferase of Roseburia intestinalis, have been associated with promoting antibody profiles characteristic of autoimmune diseases. The persistent exposure of molecular mimics from the microbiota to the human immune system is likely to be involved in autoantibody production that contributes to the pathologies associated with immune-mediated inflammatory disorders. Here-in, examples of molecular mimics that have been identified among resident members of the human microbiome and their ability to induce autoimmune disease through cross-reactive autoantibody production are discussed. Improved awareness of the molecular mimics that exist among human colonisers will help elucidate the mechanisms involved in the breakdown of immune tolerance that ultimately lead to chronic inflammation and downstream disease.

Associations between power Doppler ultrasound findings and B-mode synovitis and clinical arthritis in juvenile idiopathic arthritis using a standardised scanning approach and scoring system

OBJECTIVES

To describe power Doppler (PD) ultrasound findings in joint regions with B-mode (BM) synovitis using a standardised scanning protocol and scoring system in patients with juvenile idiopathic arthritis (JIA). Further, to examine associations between PD findings and BM synovitis, clinical arthritis, patient characteristics and disease activity.

METHODS

In this cross-sectional study, one experienced ultrasonographer, blinded to clinical findings, performed ultrasound examinations in 27 JIA patients with suspected clinical arthritis. The elbow, wrist, metacarpophalangeal 2-3, proximal interphalangeal 2-3, knee, ankle and metatarsophalangeal 2-3 joints were assessed bilaterally and scored semiquantitatively (grades 0-3) for BM and PD findings using a joint-specific scoring system with reference atlas. Multilevel mixed-effects ordered regression models were used to explore associations between PD findings and BM synovitis, clinical arthritis, age, sex, JIA subgroups, disease duration and 10-joint Juvenile Arthritis Disease Activity Score (JADAS10).

RESULTS

Twenty-one girls and six boys, median age (IQR) 8 years (6-12 years) were included. Overall, 971 joint regions were evaluated by ultrasound, 129 had BM synovitis and were assessed for PD. PD findings were detected in 45 joint regions (34.9%), most frequently in the parapatellar recess of the knee (24.4%). Increasing PD grades were associated with higher BM grades (OR=5.0,p<0.001) and with clinical arthritis (OR=7.4,p<0.001) but not with age, sex, JIA subgroups, disease duration or JADAS10.

CONCLUSION

Increasing severity of PD findings were significantly associated with BM synovitis and with clinical arthritis. This suggests that PD signals detected using a standardised ultrasound examination and scoring system can reflect active disease in JIA patients.

Diagnosis of juvenile idiopathic arthritis with asymptomatic involvement of the temporomandibular joint: A case report

Juvenile idiopathic arthritis (JIA) is a broad term that describes a group of heterogeneous rheumatologic diseases, mainly characterized by inflammation in the joints of children and young people up to 16 years of age. Its etiology is still not well understood and the diagnosis, essentially clinical, begins with the exclusion of other joint diseases. When the disease affects the temporomandibular joint, diagnosis is a challenge, as many patients are asymptomatic. The objective of this paper is to present a case of JIA with severe involvement of the temporomandibular joint and to discuss the clinical, radiographic, laboratory findings and the importance of early diagnosis. The lack of diagnosis of active arthritis in the temporomandibular joint in patients with JIA can cause irreversible effects such as micrognathia, malocclusion and reduced maximum mouth opening. Early diagnosis of temporomandibular joint involvement in JIA is important and needs to be investigated early in the clinical manifestation of systemic disease. Laboratory tests and clinical history are important to define treatment and prognosis, but not to predict temporomandibular joint arthritis. Imaging exams are important diagnostic tools to identify morphological changes in soft and hard tissues of the temporomandibular joint.

Contribution of Ultrasound in Current Practice for Managing Juvenile Idiopathic Arthritis

The interest and application of musculoskeletal ultrasound (MSUS) in juvenile idiopathic arthritis (JIA) are increasing. Numerous studies have shown that MSUS is more sensitive than clinical examination for detecting subclinical synovitis. MSUS is a well-accepted tool, easily accessible and non-irradiating. Therefore, it is a useful technique throughout JIA management. In the diagnostic work-up, MSUS allows for better characterizing the inflammatory involvement. It helps to define the disease extension, improving the classification of patients into JIA subtypes. Moreover, it is an essential tool for guiding intra-articular and peritendinous procedures. Finally, during the follow-up, in detecting subclinical disease activity, MSUS can be helpful in therapeutic decision-making. Because of several peculiarities related to the growing skeleton, the MSUS standards defined for adults do not apply to children. During the last decade, many teams have made large efforts to define normal and pathological US features in children in different age groups, which should be considered during the US examination. This review describes the specificities of MSUS in children, its applications in clinical practice, and its integration into the new JIA treat-to-target therapeutic approach.

The Role of Ultrasound in Temporomandibular Joint Disorders: An Update and Future Perspectives

Temporomandibular joint (TMJ) disorder is the second most common chronic pain condition affecting the general population after back pain. It encompasses a complex set of conditions, manifesting with jaw pain and limitation in mouth opening, influencing chewing, eating, speaking, and facial expression. TMJ dysfunction could be related to mechanical abnormalities or underlying inflammatory arthropathies, such as rheumatoid arthritis (RA) or juvenile idiopathic arthritis (JIA). TMJ exhibits a complex anatomy, and thus a thorough investigation is required to detect the TMJ abnormalities. Importantly, TMJ involvement can be completely asymptomatic during the early stages of the disease, showing no clinically detectable signs, exposing patients to delayed diagnosis, and progressive irreversible condylar damage. For the prevention of JIA complications, early diagnosis is therefore essential. Currently, magnetic resonance imaging (MRI) is described in the literature as the gold standard method to evaluate TMJ. However, it is a high-cost procedure, not available in all centers, and requires a long time for image acquisition, which could represent a problem notably in the pediatric population. It also suffers restricted usage in patients with claustrophobia. Ultrasonography (US) has emerged in recent years as an alternative diagnostic method, as it is less expensive, not invasive, and does not demand special facilities. In this narrative review, we will investigate the power of US in TMJ disorders based on the most relevant literature data, from an early screening of TMJ changes to differential diagnosis and monitoring. We then propose a potential algorithm to optimize the management of TMJ pathology, questioning what would be the role of ultrasonographic study.

The EFSUMB Guidelines and Recommendations for Musculoskeletal Ultrasound - Part II: Joint Pathologies, Pediatric Applications, and Guided Procedures

The second part of the Guidelines and Recommendations for Musculoskeletal Ultrasound (MSUS), produced under the auspices of EFSUMB, following the same methodology as for Part 1, provides information and recommendations on the use of this imaging modality for joint pathology, pediatric applications, and musculoskeletal ultrasound-guided procedures. Clinical application, practical points, limitations, and artifacts are described and discussed for every joint or procedure. The document is intended to guide clinical users in their daily practice.

Fifteen-minute guide to managing oligoarticular juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease affecting children and young people today. However, it is not a single disease entity, but an umbrella term that gathers together a heterogeneous collection of complex, chronic inflammatory conditions with oligoarticular JIA the most common form in both Europe and North America. Due to its relative rarity in daily practice and potential to mimic other conditions, oligoarticular JIA can present a diagnostic and management challenge to healthcare professionals in both primary care and general paediatrics. The aim of this article is to provide a summary of the key aspects of diagnosis, investigation and management of this condition, with the hopes of building clinicians' confidence when facing a possible case of oligoarticular JIA.

Ultraschalldiagnostik in der Kinderrheumatologie

Der Artikel gibt einen Überblick zum aktuellen Stand der Ultraschallbefundung in der Kinderrheumatologie und geht insbesondere auf den praktischen Einsatz und die technischen Aspekte der Gelenksonografie ein. Dabei werden auch die wissenschaftlichen Entwicklungen der letzten Jahre zusammengefasst und berücksichtigt. Neben der Gelenksonografie wird die Ultraschalltechnik in der Kinderrheumatologie zunehmend auch auf weitere Körperregionen und -organe ausgeweitet, die für die kinderrheumatologische Diagnostik relevant sind.

Juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is an umbrella term for arthritis of unknown origin, lasting for >6 weeks with onset before 16 years of age. JIA is the most common chronic inflammatory rheumatic condition of childhood. According to the International League Against Rheumatism (ILAR) classification, seven mutually exclusive categories of JIA exist based on disease manifestations during the first 6 months of disease. Although the ILAR classification has been useful to foster research, it has been criticized mainly as it does not distinguish those forms of chronic arthritis observed in adults and in children from those that may be unique to childhood. Hence, efforts to provide a new evidence-based classification are ongoing. Similar to arthritis observed in adults, pathogenesis involves autoimmune and autoinflammatory mechanisms. The field has witnessed a remarkable improvement in therapeutic possibilities of JIA owing to the availability of new potent drugs and the possibility to perform controlled trials with support from legislative interventions and large networks availability. The goal of drug therapy in JIA is to rapidly reduce disease activity to inactive disease or clinical remission, minimize drug side effects and achieve a quality of life comparable to that of healthy peers. As JIA can influence all aspects of a child's and their family's life, researchers increasingly recognize improvement of health-related quality of life as a key treatment goal.

Ultrasonography in Pediatric Rheumatology

This review highlights the increasing evidence from the last few years supporting the use of musculoskeletal ultrasonography (MSUS) in the evaluation and management of patients with pediatric rheumatic diseases, particularly focusing on juvenile idiopathic arthritis. Recently developed definitions for the sonographic appearance of healthy and pathologic joints in children are discussed. Further topics explored include how MSUS enhances the diagnosis of inflammatory joint disease (synovitis, enthesitis, tenosynovitis), including the detection of subclinical synovitis. There is a brief summary on the use of ultrasonography in the evaluations of myositis, Sjögren syndrome, and scleroderma.

Reliability of the Preliminary OMERACT Juvenile Idiopathic Arthritis MRI Score (OMERACT JAMRIS-SIJ)

This study reports the reliability of the juvenile idiopathic arthritis magnetic resonance imaging scoring system (JAMRIS-SIJ). The study comprised of eight raters—two rheumatologists and six radiologists—and 30 coronal T1 and Short-Tau Inversion Recovery (STIR) MRI scans of patients with enthesitis-related juvenile spondylarthritis. The median age of patients was 15 years with a mean disease duration of 5 years and 22 (73.3%) of the sample were boys. The inter-rater agreement of scores for each of the JAMRIS-SIJ items was calculated using a two-way random effect, absolute agreement, and single rater intraclass correlation coefficient (ICC 2.1). The ICC was interpreted together with kurtosis, since the ICC is also affected by the distribution of scores in the sample. The eight-rater, single measure inter-rater ICC (and kurtosis) values for JAMRIS-SIJ inflammation and damage components were the following: bone marrow edema (BME), 0.76 (1.2); joint space inflammation, 0.60 (1.8); capsulitis, 0.58 (9.2); enthesitis, 0.20 (0.1); ankylosis, 0.89 (35); sclerosis, 0.53 (4.6); erosion, 0.50 (6.5); fat lesion, 0.40 (21); backfill, 0.38 (38). The inter-rater reliability for BME and ankylosis scores was good and met the a priori set ICC threshold, whereas for the other items it was variable and below the selected threshold. Future directives should focus on refinement of the scores, definitions, and methods of interpretation prior to validation of the JAMRIS-SIJ through the assessment of its measurement properties.

Development and reliability of a novel ultrasonographic joint-specific scoring system for synovitis with reference atlas for patients with juvenile idiopathic arthritis

Objective

To develop an ultrasonographic image acquisition protocol and a joint-specific scoring system for synovitis with reference atlas in patients with juvenile idiopathic arthritis (JIA) and to assess the reliability of the system.

Methods

Seven rheumatologists with extensive ultrasound experience developed a scanning protocol and a semiquantitative joint-specific scoring system for B-mode (BM) synovitis for the elbow, wrist, metacarpophalangeal 2–3, proximal interphalangeal 2–3, hip, knee, ankle and metatarsophalangeal 2–3 joints. An ultrasonographic reference atlas for BM synovitis, divided in four age groups (2–4, 5–8, 9–12, 13–18 years), and power Doppler (PD) activity was then developed. Reliability was assessed for all joints on still images and in a live exercise including 10 patients with JIA, calculated by intraclass correlation coefficient (ICC) and weighted kappa.

Results

A scanning protocol and scoring system for multiple joints with reference atlas composed of images with four different score levels for BM and PD were developed. Still image scoring for BM synovitis on joint level showed good to excellent intra-reader reliability (ICC/kappa ranges: 0.75–0.95/0.63–0.91) and moderate to excellent inter-reader reliability (ICC/kappa ranges: 0.89–0.99/0.50–0.91). Still image scoring for PD activity showed excellent intra-reader and inter-reader reliability (ICC/kappa: 0.96/0.91 and ICC/kappa: 0.97/0.80, respectively). In the live scoring, inter-reader reliability (ICC/kappa) was moderate to excellent for BM synovitis (0.94/0.51) and PD activity (0.91/0.60).

Conclusion

An ultrasonographic image acquisition protocol and joint-specific scoring system with reference atlas were developed and demonstrated moderate to excellent reliability for scoring of synovitis in patients with JIA. This can be a valuable tool in clinical practice and future research.

Prevalence of autoimmune diseases and other associated conditions in children and young adults with juvenile idiopathic arthritis

Objective

Many autoimmune diseases share common pathogenic mechanisms; however, there are limited studies quantifying the coexistence of autoimmune diseases and associated conditions in patients with juvenile idiopathic arthritis (JIA). This large US-based study estimated and compared the prevalence of multiple coexisting autoimmune diseases in patients with JIA with a general paediatric (GP) patient population.

Methods

This retrospective cohort study was conducted using registry data from the Cincinnati Children’s Hospital Medical Center (January 2010–October 2018). The prevalence of multiple autoimmune diseases was estimated in patients (age <21 years) with JIA and a control group from the GP patient population. Crude prevalences of 26 prespecified autoimmune diseases and associated conditions were compared using Bayesian Poisson regression modelling for each year up to the end of the study period.

Results

Overall, 2026 patients were included in the JIA cohort and 41 572 in the GP cohort. Of 26 autoimmune diseases and associated conditions evaluated, 14 (53.8%) had a significantly higher prevalence in the JIA cohort compared with the GP cohort. In total, seven (26.9%) autoimmune diseases or associated conditions had a >20-fold increased prevalence in the JIA cohort compared with the GP cohort.

Conclusion

In this study, patients with JIA had a greater prevalence of a large number of coexisting autoimmune diseases and associated conditions compared with the GP population. Physicians should consider coexisting autoimmune diseases in the treatment and management of patients with JIA.

Application of the OMERACT synovitis ultrasound scoring system in juvenile idiopathic arthritis: a multicenter reliability exercise

OBJECTIVES

To evaluate the reliability of the OMERACT paediatric ultrasound (US) synovitis definitions and scoring system in JIA.

METHODS

Thirteen sonographers analysed 75 images for the presence/absence of elementary lesions (binary scoring) and for grading synovitis, synovial hypertrophy, effusion and Doppler signals. Static US images of the second metacarpophalangeal joint (MCP-II), wrist, elbow, knee and ankle in JIA patients at different ages and different disease stages were collected with standardized scanning by two experienced sonographers. Intra- and inter-reader reliability were analysed with kappa coefficients.

RESULTS

Intra-reader reliability was good for binary scoring (Cohen's kappa 0.62, range 0.47-0.75), synovitis and synovial hypertrophy; excellent for Doppler signals (quadratic weighted kappa 0.77, 0.66-0.86; 0.76, 0.61-0.84; and 0.87, 0.77-0.94, respectively); and moderate for effusion (0.55, 0.24-0.76). Inter-reader reliability was good for synovitis and synovial hypertrophy (Light's kappa 0.68, 95% CI: 0.61, 0.75 and 0.63, 0.54-0.71, respectively), excellent for Doppler signals (0.85, 95% CI: 0.77, 0.90), and moderate for binary scoring and effusion (0.48, 95% CI: 0.36, 0.64 and 0.49, 0.40-0.60, respectively). We obtained the best scores for the knee (0.71, 0.54-0.85) except for Doppler signals, with reliability higher for MCP-II. We found a trend toward better results in older children.

CONCLUSIONS

This is the first study establishing the reliability of the OMERACT paediatric US synovitis definitions and scoring system in the five most commonly affected joints in JIA. The reliability was good among a large group of sonographers. These results support the applicability of these definitions and scoring system in clinical practice and multicentre studies.

Atlas of MRI findings of sacroiliitis in pediatric sacroiliac joints to accompany the updated preliminary OMERACT pediatric JAMRIS (Juvenile Idiopathic Arthritis MRI Score) scoring system: Part II: Structural damage lesions

Magnetic resonance imaging (MRI) is the imaging modality of choice for identifying sacroiliitis in juvenile idiopathic arthritis (JIA). Besides active lesions of sacroiliitis, of which bone marrow edema (BME) is the key feature, structural damage lesions can also be detected. Structural changes include erosion, sclerosis, fat lesion, backfill and ankylosis, and are more common at later stages. Systematic MRI assessment of inflammation and structural damage may aid in monitoring the course of the disease and evaluating treatment options. In this pictorial essay, we illustrate normal MRI findings and growth-related changes of the SIJ in the pediatric population, as well as the different MRI features of structural damage of sacroiliitis. This atlas can serve as a reference for assessing structural lesions of SIJ arthritis according to the updated preliminary JAMRIS (Juvenile Idiopathic Arthritis MRI Score) scoring system proposed by the MRI in JIA working group of Outcome Measures in Rheumatology and Clinical Trials (OMERACT). The atlas is intended to be read in conjunction with its companion Part 1, Active Lesions.

Atlas of MRI findings of sacroiliitis in pediatric sacroiliac joints to accompany the updated preliminary OMERACT pediatric JAMRIS (Juvenile Idiopathic Arthritis MRI Score) scoring system: Part I: Active lesions

Magnetic resonance imaging (MRI) is an increasingly important tool for identifying involvement of the sacroiliac joints (SIJ) in juvenile idiopathic arthritis (JIA). The key feature for diagnosing active sacroiliitis is bone marrow edema (BME), but other features of active arthritis such as joint space inflammation, inflammation in an erosion cavity, capsulitis and enthesitis can be seen as well. Structural changes may also be seen. Systematic MRI assessment of inflammation and structural damage may aid in monitoring the disease course, choice of therapeutics and evaluating treatment response. In this pictorial essay, we illustrate normal MRI findings and growth-related changes of the SIJ in the pediatric population, as well as the different MRI features of SIJ inflammation. This atlas demonstrates fundamental MRI disease features of active inflammation in a format that can serve as a reference for assessing SIJ arthritis according to the updated preliminary JAMRIS (Juvenile Idiopathic Arthritis MRI Score) scoring system proposed by the MRI in JIA working group of Outcome Measures in Rheumatology and Clinical Trials (OMERACT). The atlas is intended to be read in conjunction with its companion Part 2, Structural Lesions.

The new role of musculoskeletal ultrasound in the treat-to-target management of juvenile idiopathic arthritis

This article reviews the role of musculoskeletal ultrasound (MSUS) for the diagnosis, monitoring and treat-to-target management of JIA. Technological advancements in MSUS allow more precise evaluation of arthritis, tenosynovitis and enthesitis versus clinical examination alone, which may assist treatment decisions. In adult studies, serum and synovial biomarkers have correlated with MSUS findings. Within paediatric rheumatology, significant developments in the definition of normal and pathology, a necessity for the future integration of MSUS into treat-to-target management, have already been reached or are underway, which in turn could allow tighter control of disease activity and earlier identification of treatment response and failure, bringing the goal of 'precision medicine' closer. Additionally, the utility of MSUS for the evaluation of subclinical disease remains an unexamined area of interest. 'Ultrasound remission' combined with clinical assessment and immunological markers could therefore potentially improve the treat-to-target management of JIA.

Spinal involvement in juvenile idiopathic arthritis: what do we miss without imaging?

Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease of childhood. Enthesitis-related arthritis (ERA) has been one of the most controversial subtypes of JIA with a higher risk of axial involvement.  Our aim was to assess the frequency and spectrum of MRI findings of spine involvement in patients with JIA and determine if the axial involvement is always clinically symptomatic in patients with positive MRI findings. In this retrospective cross-sectional observational study we included known or suspected JIA patients who underwent spinal MRI examination between 2015 and 2017 and followed up in the Pediatric Rheumatology outpatient clinic. The demographic and clinical data were reviewed from the medical charts and electronic records. All patients were grouped as clinically symptomatic and asymptomatic for spinal involvement and MRI findings were re-evaluated for presence of inflammatory and erosive lesions. Of the 72 JIA patients, 57 (79.2%) were diagnosed with ERA, and 15 (20.8%) with non-ERA subtypes of JIA. Overall, 49 (68%) patients with JIA had positive spinal MRI findings (inflammatory and/or erosive lesions). Twenty-seven (47%) ERA patients were clinically symptomatic for spine involvement and among them, 19 (70.3%) had positive spinal MRI findings. Although 30 ERA (53%) patients were clinically asymptomatic, 23 of them (77%) had positive spinal MRI findings, as well. Eleven (73%) patients diagnosed with non-ERA JIA subtypes were clinically symptomatic for spine involvement at the time of MRI. Among them, four (36.3%) had inflammatory and/or erosive lesions on spine MRI. Four (26%) non-ERA patients were clinically asymptomatic for spine involvement, but three (75%) of them showed positive findings on spinal MRI. Inflammatory and/or erosive lesions of the thoracolumbar spine could exist in patients with JIA, regardless of the presence of symptoms. Not only because the significant proportion of ERA patients show asymptomatic axial involvement but also the presence of axial involvement in patients who were classified as non-ERA depending on current ILAR classification underlines the necessity of using MRI for accurate classification of patients with JIA.

Age, gender, height and weight in relation to joint cartilage thickness among school-aged children from ultrasonographic measurement

BACKGROUND

Among school-age children, the decrease of cartilage thickness (Cth) with increasing age is well known. However, the influence of body mass index (BMI), height or weight on Cth has not been revealed. Here in, we aim to establish an age- and gender-specific Cth standard reference among Asians and investigate the possible prestige of BMI, height and weight.

METHODS

A cross-sectional study was performed in healthy Asian children. Bilateral knees, ankles, wrists, second metacarpophalangeals (MCPs) and proximal interphalangeals (PIPs) were measured using ultrasound. The children's height, weight and BMI were also recorded for later adjustment.

RESULTS

A total of 200 school age Asian children (including 86 girls and 114 boys, aged between 5 to 13 years-old) were investigated. Cth differences were observed in the knees, ankles, wrists, MCPs and PIPs between sexes (p < 0.05), with girls having thinner cartilage thickness. While Cth decreases with increasing age (p < 0.0001, 0.039, 0.001, 0.023, 0.091 in girls' knees, ankles, wrists, MCPs and PIPs and p = 0.002, 0.001, < 0.0001, 0.001, 0.045 in boys', respectively). Our data showed that weight, height and BMI are not the main factors contributing to Cth. A formula to calculate gender-specific cartilage thickness for Asian school age children is suggested. There was no difference in Cth after adjusting for height or weight between Asian or Caucasian group.

CONCLUSIONS

A formula to calculate gender-specific cartilage thickness for Asian school age children is suggested. Height, weight and BMI were not the major contributor for Cth among school age children.

Changes in Treatments and Outcomes After Implementation of a National Universal Access Program for Juvenile Idiopathic Arthritis

OBJECTIVE

To evaluate the clinical and demographic characteristics of patients with juvenile idiopathic arthritis ( JIA) in Chile and compare treatments and outcomes before and after the introduction in 2010 of the Explicit Health Guarantees (GES) for JIA, a national universal access program for diagnosis and treatment of this condition.

METHODS

The clinical records of 280 patients with JIA followed at a private tertiary academic health network between 2007 and 2018 were reviewed.

RESULTS

Seventy percent of patients with JIA were female, mean age at diagnosis was 8.5 ± 4.8 years and mean follow-up was 4.0 ± 3.7 years. After GES implementation (post-GES), time to evaluation by pediatric rheumatologist and diagnostic delay were significantly reduced (15.0 ± 4.5 vs 9.0 ± 4.2 months, P = 0.004). In addition, use of magnetic resonance imaging significantly increased post-GES (P < 0.001). In terms of JIA treatments, before GES implementation, no patients received biologics. Of the 67 patients diagnosed before 2010 with continued follow-up at our center, 34% began biologic treatment after GES implementation. Of 196 patients diagnosed post-GES, 46% were treated with biologics. JIA remission rates were significantly higher in patients diagnosed post-GES compared to pre-GES (43% vs 29%, P = 0.02). Post-GES, we observed a significant decrease in uveitis complications among JIA patients (45% vs 13%, P = 0.04).

CONCLUSION

The implementation of a national government-mandated universal access program for guaranteed JIA diagnosis and treatment led to earlier access to a pediatric rheumatologist and JIA diagnosis, increased rates of treatment with biologic drugs, higher rates of clinical remission, and lower rates of uveitis complications in Chilean children with JIA.

Genetic disorders with symptoms mimicking rheumatologic diseases: A single-center retrospective study

Musculoskeletal symptoms may be due to noninflammatory causes, including genetic disorders. We aimed to examine the final genetic diagnosis in patients who presented with musculoskeletal complaints to the rheumatology department. Patients who presented to the Department of Pediatric Rheumatology and were referred to the pediatric genetic department between January 2015 and May 2019 were evaluated retrospectively. A total of 60 patients, 19 boys (31.66%), with a mean age of 12.46 ± 1.41 years were included in the study. The total consanguinity rate was 25%. The most common (29.5%) cause of referral to the pediatric genetic department was the presence of skeletal anomalies (such as camptodactyly, clinodactyly, and short stature) with accompanying joint findings. Approximately one-third of the patients (n: 19) were diagnosed and followed up by the pediatric genetics department. The diagnoses of patients were as follows: camptodactyly, arthropathy, coxa vara, and pericarditis (CACP) syndrome (n: 3); trichorhinophalangeal syndrome (n: 1); progressive pseudorheumatoid dysplasia (n: 2); LIG4 syndrome (n: 1); H syndrome (n: 1); spondyloenchondrodysplasia (SPENCD) (n: 3); and nonspecific connective tissue disorders (n: 8). In the differential diagnosis of patients who are referred to the Department of Pediatric Rheumatology with complaints of the musculoskeletal system, genetic disorders should also be considered.

Toward Developing a Semiquantitative Whole Body-MRI Scoring for Juvenile Idiopathic Arthritis: Critical Appraisal of the State of the Art, Challenges, and Opportunities

With powerful new therapies available for management of juvenile idiopathic arthritis (JIA), early diagnosis leading to appropriate treatment may prevent long-term structural joint damage. Although magnetic resonance imaging (MRI) is typically used to assess individual body parts, indications for whole body (WB) MRI are increasing. Its utility as a diagnostic and monitoring tool has already been widely investigated in adult rheumatology patients, but less so in pediatric rheumatologic patients. This paper is a comprehensive review of scoring systems and a proposal for the conceptual development of a WB-MRI scoring system for the evaluation of JIA. In this review we identify, summarize, and critically appraise the available literature on the use of WB-MRI in inflammatory arthritis, addressing relevant considerations on components of a classification system that can lead to the development of a future pediatric WB-MRI scoring system for use in children with JIA. We also discuss advantages and challenges of developing such a WB-MRI scoring system for assessment of JIA and outline next steps toward the conceptual development of this scoring system.

Magnetic resonance imaging of the knee joint in juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is an umbrella term for a group of diseases in children younger than 16 years old lasting six weeks or longer. Synovitis may lead to destructive and irreversible joint changes with subsequent functional impairment. Prompt diagnosis is essential to prevent permanent joint damage and preserve joint functionality. In the course of JIA both the axial and peripheral skeleton may be involved in the inflammatory process, but the knee joint is most frequently affected. New drugs and treatment protocols have forced the need for diagnosis at the earliest possible stage. Magnetic resonance imaging (MRI) allows early detection of lesions and constitutes a superior diagnostic imaging method. Synovitis, tenosynovitis, enthesitis, bursitis, osteitis, cartilage loss, bone cysts, and erosions are lesions diagnosed in JIA, and they can be precisely imaged in MRI. This article aims to present MRI inflammatory features of the knee in children with JIA based on the literature.

Current status of MR imaging of juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is the most common chronic arthropathy in the pediatric population. Although the diagnosis is essentially clinical for many affected joints, MR imaging has become an important tool for the assessment of joints that are difficult to evaluate clinically, such as temporomandibular and sacroiliac joints, and for screening of inflammatory changes in the entire body by whole body MRI (WBMRI) assessment. The utilization of MR imaging is challenging in the pediatric population given the need for discrimination between pathological and physiological changes in the growing skeleton. Several multicentric multidisciplinary organizations have made major efforts over the past decades to standardize, quantify, and validate scoring systems to measure joint changes both cross-sectionally and longitudinally according to rigorous methodological standards. In this paper, we (1) discuss current trends for the diagnosis and management of JIA, (2) review challenges for detecting real pathological changes in growing joints, (3) summarize the current status of standardization of MRI protocols for data acquisition and the quantification of joint pathology in JIA by means of scoring systems, and (4) outline novel MR imaging techniques for the evaluation of anatomy and function of joints in JIA. Optimizing the role of MRI as a robust biomarker and outcome measure remains a priority of future research in this field.

Ultrasound imaging in paediatric rheumatology

The role of ultrasound imaging in the diagnosis and monitoring of paediatric rheumatic diseases with special emphasis on recent scientific work regarding the evidence base and standardization of this technique is being reviewed. An overview of the most important practical aspects for the use of musculoskeletal ultrasound in a clinical setting is also provided. Huge scientific efforts and advances in recent years illustrate the increasing importance of musculoskeletal ultrasound in pediatric rheumatology. Several studies focused on setting an evidence-based standard for the ultrasound appearance of healthy and normal joints in children of all age groups. Physiologic vascularization and ossification were two main aspects of these studies. Other publications demonstrate that ultrasound imaging is also an important and useful tool to detect pathology as synovitis, tenosynovitis or enthesitis in children and to monitor pediatric patients with rheumatic conditions. Important practical aspects include training in the use of correct ultrasound techniques, as well as knowledge and experience of normal pediatric sonoanatomy and the appearance of pathological findings on ultrasound.

Thermal and Visual Imaging to Assist with Juvenile Idiopathic Arthritis Examination of the Knees

Juvenile idiopathic arthritis (JIA) causes inflammation of the joints, and it is frequently associated with their pain and stiffness. Its timely diagnosis is important to avoid its progressive damage to the bones and cartilage. Increases in the joint’s temperature and redness could be indicators of active JIA, hence their accurate quantification could assist with diagnosis. Thermal and visual images of the knees in 20 JIA participants (age: mean = 11.2 years, standard deviation = 2.3 years) were studied. The median temperature of knees with active inflammation was 3.198% higher than that of inactive knees. This difference, examined by a Wilcoxon signed-rank test, was statistically significant (p = 0.0078). In six out of the eight participants who had one active inflamed knee, thermal imaging identified the corresponding knee as warmer. In 16 out of 20 participants, the knee identified as warmer by thermal imaging was also identified as having a greater colour change by visual imaging as compared to their respective reference regions. The devised methods could accurately quantify the colour and temperature of the knees. It was concluded that thermal and visual imaging methods can be valuable in examining JIA. Further studies involving a larger number of participants and more detailed explorations would be needed prior to clinical application.

The Role of Ultrasound in Juvenile Idiopathic Arthritis: A Narrative Review From an Imaging Perspective

Objective:

Musculoskeletal sonography (MSKS) is increasingly being used in the setting of juvenile idiopathic arthritis (JIA). The purpose of this narrative review was to describe the role of sonography in JIA and outline strategies for operators of pediatric MSKS.

Methods:

A literature review through multiple medical databases was conducted by restricting the search to medical subject headings (MeSH). Peer-reviewed English-language articles from 2007 to 2018 were included, which focused the on common sonographic findings of JIA.

Results:

Twenty-six articles were selected for inclusion in the study after a complete reading. Many studies aimed to address the validity of sonographic techniques in the assessment of JIA, but few studies discussed the specific sonographic appearances of JIA, scanning pitfalls, and appropriate imaging techniques.

Conclusion:

MSKS reveals subclinical manifestations of arthropathy, but the true value of detecting subclinical disease is not well understood. MSKS is limited in the evaluation of articular cartilage thinning and bony erosions. Responsiveness of MSKS in JIA remains to be formally assessed with higher quality studies.

Linking Joint Impairment and Gait Biomechanics in Patients with Juvenile Idiopathic Arthritis

Juvenile Idiopathic Arthritis (JIA) is a paediatric musculoskeletal disease of unknown aetiology, leading to walking alterations when the lower-limb joints are involved. Diagnosis of JIA is mostly clinical. Imaging can quantify impairments associated to inflammation and joint damage. However, treatment planning could be better supported using dynamic information, such as joint contact forces (JCFs). To this purpose, we used a musculoskeletal model to predict JCFs and investigate how JCFs varied as a result of joint impairment in eighteen children with JIA. Gait analysis data and magnetic resonance images (MRI) were used to develop patient-specific lower-limb musculoskeletal models, which were evaluated for operator-dependent variability (< 3.6°, 0.05 N kg-1 and 0.5 BW for joint angles, moments, and JCFs, respectively). Gait alterations and JCF patterns showed high between-subjects variability reflecting the pathology heterogeneity in the cohort. Higher joint impairment, assessed with MRI-based evaluation, was weakly associated to overall joint overloading. A stronger correlation was observed between impairment of one limb and overload of the contralateral limb, suggesting risky compensatory strategies being adopted, especially at the knee level. This suggests that knee overloading during gait might be a good predictor of disease progression and gait biomechanics should be used to inform treatment planning.

Juvenile spondyloarthritis and chronic recurrent multifocal osteomyelitis overlap syndrome in a 16-year-old adolescent. A case report and literature review

The authors present a very rare case of juvenile spondyloarthritis and chronic recurrent multifocal osteomyelitis overlap syndrome in a 16-year-old girl and discuss diagnostic difficulties associated with this case. Juvenile spondyloarthropathies are a type of rheumatic diseases characterized by non-symmetrical peripheral arthritis and enthesitis as well as by spondylitis. Chronic recurrent multifocal osteomyelitis is a rare, possibly autoimmune disease found primarily in children and adolescents. The disease is characterized by bone marrow inflammation and the presence of lytic and sclerotic lesions. Diagnostic imaging plays a key role in the identification of both diseases. The primary modality is X-ray; however, currently, magnetic resonance imaging and ultrasound are increasingly important. A correct early diagnosis allows one to start appropriate treatment to reduce the consequences of these diseases.

Preliminary Definitions for Sacroiliac Joint Pathologies in the OMERACT Juvenile Idiopathic Arthritis Magnetic Resonance Imaging Score (OMERACT JAMRIS-SIJ)

OBJECTIVE

To develop definitions for the assessment of magnetic resonance imaging (MRI) pathologies of the sacroiliac joints (SIJ) in juvenile idiopathic arthritis.

METHODS

An Outcome Measures in Rheumatology (OMERACT) consensus-driven methodology consisting of iterative surveys and focus group meetings within an international group of rheumatologists and radiologists.

RESULTS

Two domains, inflammation and structural, were identified. Definitions for bone marrow edema, joint space inflammation, capsulitis, and enthesitis were derived for joint inflammation; sclerosis, erosion, fatty lesion, and ankylosis were defined for assessing structural joint changes.

CONCLUSION

Preliminary consensus-driven definitions for inflammation and structural elements have been derived, underpinning the ongoing development of the OMERACT Juvenile Arthritis MRI SIJ scoring system (OMERACT JAMRIS-SIJ).

Prevalence and course of lower limb disease activity and walking disability over the first 5 years of juvenile idiopathic arthritis: results from the childhood arthritis prospective study

Objective

The aim was to investigate the time course of lower limb disease activity and walking disability in children with JIA over a 5-year course.

Methods

The Childhood Arthritis Prospective Study is a longitudinal study of children with a new JIA diagnosis. Childhood Arthritis Prospective Study data include demographics and core outcome variables at baseline, 6 months and yearly thereafter. Prevalence and transition rates from baseline to 5 years were obtained for active and limited joint counts at the hip, knee, ankle and foot joints; and walking disability, measured using the Childhood Health Assessment Questionnaire walking subscale. Missing data were accounted for using multiple imputation.

Results

A total of 1041 children (64% female), with a median age of 7.7 years at first visit, were included. Baseline knee and ankle synovitis prevalence was 71 and 34%, respectively, decreasing to 8–20 and 6–12%, respectively, after 1 year. Baseline hip and foot synovitis prevalence was <11%, decreasing to <5% after 6 months. At least mild walking disability was present in 52% at baseline, stabilizing at 25–30% after 1 year.

Conclusion

Lower limb synovitis and walking disability are relatively common around the time of initial presentation in children and young people with JIA. Mild to moderate walking disability persisted in ∼25% of patients for the duration of the study, despite a significant reduction in the frequency of lower limb synovitis. This suggests that there is an unmet need for non-medical strategies designed to prevent and/or resolve persistent walking disability in JIA.

Educational initiatives and training for paediatric rheumatology in Europe

The Paediatric Rheumatology European Society (PReS) has over many years, developed a portfolio of educational activities to address increasing educational needs of workforce and support young clinicians to acquire skills to develop new knowledge and deliver clinical care in the future. These educational activities aim to facilitate growth of paediatric rheumatology and ultimately improve the clinical care for children and families. This article describes the current portfolio of PReS educational activities and their relevance to the international paediatric rheumatology community.

Feasibility of a musculoskeletal ultrasound intervention to improve adherence in juvenile idiopathic arthritis: a proof-of concept trial

BACKGROUND

Non-adherence is a prevalent and modifiable issue in juvenile idiopathic arthritis (JIA) that currently lacks provider-based intervention. Education surrounding disease status is one way in which families remain engaged in their care. Musculoskeletal ultrasound is one such form of demonstrative, real-time education that may impact the way patients and caregivers self-manage their disease. The aims of this study are to 1) assess the feasibility, acceptability and perceived usefulness of musculoskeletal ultrasound as a non-adherence intervention tool and 2) to examine changes in methotrexate adherence in adolescents with JIA following the ultrasound.

METHODS

Eight adolescents with polyarticular or extended oligoarticular JIA and their caregivers completed this 12 week study. A within subject design was used to compare baseline and post-intervention adherence, quality of life and disease activity indices. Adherence measures included electronic measurement of methotrexate in addition to self-reported adherence questionnaires. The ultrasound intervention included a one-time, rheumatologist provided, educational examination of three or more currently or historically active joints.

RESULTS

The ultrasound intervention was found to be both feasible and acceptable. One hundred percent of eligible participants completed the ultrasound intervention. The ultrasound was well received by patients and caregivers, with most believing this to be a helpful tool. Baseline adherence was 75.3% among participants, with half of the participants being classified as non-adherent. Electronically measured and self-reported adherence measures did not show significant changes during the post-intervention period. Two participants improved, four participants maintained, and two participants decreased adherence. On ultrasound, 18/27 (66.7%) of the examined joints displayed abnormalities, with 63% being discrepant and additive to the rheumatologist's physical examination.

CONCLUSIONS

While our intervention did not show any changes in adherence, quality of life or disease activity indices in this proof-of-concept trial, the intervention does show promise in acceptability measures and merits future study in a more robust trial design. An additional study benefit was that the musculoskeletal ultrasound intervention was able to demonstrate subclinical disease, leading to clinically impactful therapeutic changes in several participants.

Reliability of ultrasonography to detect inflammatory lesions and structural damage in juvenile idiopathic arthritis

BACKGROUND

Musculoskeletal Ultrasonography (MSUS) is an important tool for the clinical assessment in Juvenile Idiopathic Arthritis (JIA). The objective of this study was to evaluate the reliability of MSUS to detect elementary lesions: synovitis, tenosynovitis, cartilage damage and bone erosions in the wrist and metacarpal (MCP) joints of patients with JIA.

METHODS

Thirty children in various subgroups of JIA according to ILAR criteria, were included in this cross-sectional study. Clinical data including painful, swollen and limited joints were recorded. Five rheumatologist ultrasonographers, blinded to the clinical evaluation, evaluated the presence of elementary lesions in the wrist and MCP 2 and 3 joints bilaterally. The synovitis was graded in B-Mode and Power Doppler (PD). In addition to descriptive statistics intra- and inter-observer reliability was calculated using Cohen's kappa according to Landis and Koch.

RESULTS

US detected more synovitis than the clinical examination (62% vs 28%, 30% vs 23% and 22% vs 17% in the wrist, second and third MCP joints respectively). The intra-observer concordance for synovitis in all joints was excellent in B-Mode (k 0.84 .63-1.0 p = 0.001), except for MCP 2, where it was good (0.61, IC 95% .34-89, p = 0.001). For both modalities (PD, B-Mode) tenosynovitis, cartilage damage and bone erosions it was also excellent. Regarding synovitis grading the concordance was excellent for all grades (0.83-1.0, IC 95% 0.51.1.0, p = 0.001), except for grade 1 where it was good (0.61, IC 95% 0.43-.83, p = 0.001). Reliability inter-observer for grayscale synovitis (0.67-0.95, IC 95% 0.67-1.0, p = 0.001), tenosynovitis grayscale (0.89, IC 95% 0.78-0.99, p.001), damage cartilage (0.89, IC 95% 0.78-0.99, p = 0.001), PD (0.66, IC 95% 0.39-1.0, p = 0.001). The concordance for grading synovitis was excellent, but for grayscale grade 1 and 2 (.66, IC 95% .53-.74, p = 0.007) and PD grade 1 and 2 (0.63, IC 95% .58-.91, p = 004) was good.

CONCLUSIONS

The intra- and inter-observer reliability of MSUS for inflammatory and structural lesions is good to excellent for the wrist and MCP in patients with JIA.

Correction to: Melatonin as an alternative sedation method during magnetic resonance imaging in preschool children with musculoskeletal problems

AbstractMagnetic resonance imaging (MRI) in preschool children is often challenging due to excessive motion artifacts. Sedation or general anesthesia (GA) are commonly used to prevent children from moving in the MRI scanner, with increased risk for cardiopulmonary complications and requirement for skilled personnel. Herein we investigated whether oral melatonin, a natural hormone implicated in circadian rhythm regulation, could be used as an alternative sedation method prior to the MRI in preschool children with musculoskeletal problems. Fifteen children with suspected juvenile idiopathic arthritis underwent a total of 16 MRI examinations following administration of 10 mg of oral melatonin; satisfactory images were obtained in all but one case, with no adverse events.Conclusion: The use of melatonin before the musculoskeletal MRI in preschool children is an effective, safe and inexpensive alternative to standard sedation and general anesthesia in preventing motion artifacts. What is known: • Magnetic resonance imaging (MRI) is a well-recognized diagnostic method to visualize synovial inflammation and changes of cartilage and bone in juvenile idiopathic arthritis.• MRI examination requires sedation or general anesthesia to ensure immobility in children who are uncooperative. What is new: • Additional to previous published studies we were able to show that melatonin for sedation for an MRI of joints, even without sleep deprivation, in the studied population may provide an alternative in children without behavioral problems, in order to avoid sedation/GA.

Melatonin as an alternative sedation method during magnetic resonance imaging in preschool children with musculoskeletal problems

Magnetic resonance imaging (MRI) in preschool children is often challenging due to excessive motion artifacts. Sedation or general anesthesia (GA) is commonly used to prevent children from moving in the MRI scanner, with increased risk for cardiopulmonary complications and requirement for skilled personnel. Herein, we investigated whether oral melatonin, a natural hormone implicated in circadian rhythm regulation, could be used as an alternative sedation method prior to the MRI in preschool children with musculoskeletal problems. Fifteen children with suspected juvenile idiopathic arthritis underwent a total of 16 MRI examinations following administration of 10 mg of oral melatonin; satisfactory images were obtained in all but one case, with no adverse events.

CONCLUSION

The use of melatonin before the musculoskeletal MRI in preschool children is an effective, safe, and inexpensive alternative to standard sedation and general anesthesia in preventing motion artifacts. What is Known: • Magnetic resonance imaging (MRI) is a well-recognized diagnostic method to visualize synovial inflammation and changes of cartilage and bone in juvenile idiopathic arthritis. • MRI examination requires sedation or general anesthesia to ensure immobility in children who are uncooperative. What is New: • Melatonin without sleep deprivation is efficacious and safe alternative to conventional sedation and general anesthesia before the musculoskeletal contrast-enhanced MRI in preschool children with JIA with timely insertion of intravenous cannula.