Enthesitis-related arthritis: current perspectives

Application of the new classification proposal for juvenile idiopathic arthritis of the pediatric rheumatology international trials organization in a group of Mexican patients

Objective

Apply the PRINTO classification proposal for diagnosing Juvenile Idiopathic Arthritis (JIA) to Mexican patients, analyzing demographic, clinical, and laboratory characteristics.

Material and methods

Cross-sectional study analyzing patients diagnosed with JIA using International League of Associations for Rheumatology (ILAR 2001) criteria over two years at a national rheumatic disease center. Reclassification was done using the Pediatric Rheumatology International Trials Organization (PRINTO) proposal. Comparisons were made between antinuclear antibodies (ANAs) positive vs. negative and rheumatoid factor (RF) positive vs. negative patients.

Results

Seventy-six patients were analyzed, mostly female. Median age was lower in systemic JIA (sJIA) and early onset JIA with positive ANAs (eoANA JIA). ANAs was present in 78.6% of patients. Reclassification according to PRINTO disorders showed RF positive polyarticular JIA, sJIA, and enthesitis-related JIA (ER JIA) reclassified to RF JIA, sJIA, and enthesitis/spondylitis-related JIA (ESR JIA) by 100%, 94.7%, and 80%, respectively. The ILAR category with the most variation was RF negative polyarticular JIA. Early disease onset was associated with a lower probability of positive RF after adjusting for sex, age, and ANAs. No association was found between ANAs positive vs. negative in adjusted multivariate analysis.

Conclusions

We found compatibility of sJIA, RF positive polyarticular JIA, and RE JIA categories with sJIA, RF JIA, and ESR JIA disorders, respectively. Differences were noted in variables such as sex and the number of affected joints. There was high ANAs positivity; however, few patients were classified into eoANA JIA disorder, with only one presenting uveitis. Most patients were classified as other JIA.

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.

Advances in the Diagnosis and Treatment of Enthesitis-Related Arthritis

Enthesitis-related arthritis (ERA) represents 5-30% of all cases of juvenile idiopathic arthritis (JIA) and belongs to the spectrum of the disorders included in the group of juvenile spondyloarthritis. In the last decade, there have been considerable advances in the classification, diagnosis, monitoring, and treatment of ERA. New provisional criteria for ERA have been recently proposed by the Paediatric Rheumatology INternational Trials Organisation, as part of a wider revision of the International League of Associations for Rheumatology criteria for JIA. The increased use of magnetic resonance imaging has shown that a high proportion of patients with ERA present a subclinical axial disease. Diverse instruments can be used to assess the disease activity of ERA. The therapeutic recommendations for ERA are comparable to those applied to other non-systemic JIA categories, unless axial disease and/or enthesitis are present. In such cases, the early use of a TNF-alpha inhibitor is recommended. Novel treatment agents are promising, including IL-17/IL-23 or JAK/STAT pathways blockers.

Juvenile Idiopathic Arthritis

Juvenile idiopathic arthritis (JIA) comprises a group of heterogenous disorders characterized by childhood-onset chronic joint inflammation. It is the most common rheumatologic disease in the pediatric population and an important cause of chronic illness in children. Early recognition and treatment are vital to prevent sequelae of uncontrolled inflammation on the developing skeleton. JIA can have significant complications that general pediatricians should be aware of, especially uveitis, which can be insidious and asymptomatic in very young children, and macrophage activation syndrome, which can be life-threatening if not recognized and appropriately treated. Although advances have been made in the past few decades, the etiology of JIA remains incompletely understood. Efforts are underway to refine the classification of JIA. The currently accepted classification scheme identifies subsets of JIA that are important clinically in terms of prognosis and tailoring treatment approaches. However, it is limited in identifying homogenous groups of children with early childhood onset and antinuclear antibody positivity, which may have different pathogenic mechanisms that could be important in developing more targeted and effective treatment approaches in the future. Treatment strategies for JIA have changed significantly in recent years with the availability of multiple newer targeted therapies, often modeled after medications used in adult-onset forms of arthritis. These treatments, and likely many others to come, have markedly improved symptom control and reduced complications in patients with JIA.

Revising diagnosis of juvenile idiopathic arthritis in adults: a single-center retrospective study

The study aimed to assess how many adult patients with juvenile idiopathic arthritis (JIA) treated with biologics fulfill classification criteria for adult rheumatic diseases and to evaluate the course of JIA in adulthood. 138 patients with JIA over 18 years old treated with biologics were included in a cross-sectional observative study. Among 138 adult patients with JIA treated with biologics, 81 patients remained with JIA diagnosis. 57 patients were rediagnosed. 31 patients met the criteria for spondyloarthropathy, among them 18 patients for ankylosing spondylitis, 10 patients for psoriatic arthritis, and 3 patients for non-radiographic axial spondyloarthritis. Rheumatoid arthritis was diagnosed in 24 patients and adults' Still disease in 2 patients. 84 patients of all adults with JIA received one biologic agent, 40 received two biologic agents, and 14 received three or more biologic therapies. 10 patients received biologic agents out of recommendations for JIA. Of the adult JIA patients treated with biologics, 41% met the classification criteria for adult inflammatory diseases. Spondyloarthropathy and rheumatoid arthritis were most commonly diagnosed. Nearly 40% of adult JIA patients required at least one modification of biological treatment. Therefore, it is worth considering a revision of JIA to adult-onset inflammatory disease entities, as it broadens the spectrum of disease-modifying drugs.

Enthesitis-related arthritis: the clinical characteristics and factors related to MRI remission of sacroiliitis

Background

To describe the clinical characteristics and explore the factors related to the MRI remission of sacroiliitis in patients with enthesitis-related arthritis (ERA).

Methods

Patients with ERA from 2018–2022 in our medical center were retrospectively reviewed, which identified according to Pediatric Rheumatology International Trials Organization (PRINTO) criteria. Demographics, clinical characteristics, examinations, and treatments were described. Univariate and multivariate logistic regression models were used to analyze the factors related to MRI remission of sacroiliitis in ERA.

Results

This retrospective study included 160 ERA patients (51.9% male) with a mean onset age of 9.2 ± 3.0 years. There were 144 cases (81.9%) with peripheral arthritis, and the hip, knee, and ankle joints were the most commonly involved joints. Enthesitis occurred in 48 cases (30.0%), and sacroiliitis occurred in 142 cases (88.5%) at diagnosis. Human leukocyte antigen (HLA)-B27 was positive in 33 cases (17.1%), and acute uveitis occurred in 3 cases (1.9%). The majority of patients (93.7%) were treated with disease-modifying anti-rheumatic drugs (DMARDs), and 60% with biologics. Among 62 patients with MRI-defined sacroiliitis, 27 (43.5%) cases showed improvement in the sacroiliac joint lesion after treatment. Multivariate logistic regression analysis showed that duration from onset to diagnosis of less than 3 months (OR = 3.609, 95% CI: 1.068–12.192) and active joints of more than 4 (OR = 4.916, 95% CI: 1.006–24.037) were independent factors.

Conclusion

We highlighted differences in ERA clinical characteristics. Patients with a shorter diagnosis time and more joint involvement improved more significantly in sacroiliac joint lesions after treatment.

Identification of Novel Loci Shared by Juvenile Idiopathic Arthritis Subtypes Through Integrative Genetic Analysis

OBJECTIVE

Juvenile idiopathic arthritis (JIA) is the most common chronic immune-mediated joint disease among children and encompasses a heterogeneous group of immune-mediated joint disorders classified into 7 subtypes according to clinical presentation. However, phenotype overlap and biologic evidence suggest a shared mechanistic basis between subtypes. This study was undertaken to systematically investigate shared genetic underpinnings of JIA subtypes.

METHODS

We performed a heterogeneity-sensitive genome-wide association study encompassing a total of 1,245 JIA cases (classified into 7 subtypes) and 9,250 controls, followed by fine-mapping of candidate causal variants at each genome-wide significant locus, functional annotation, and pathway and network analysis. We further identified candidate drug targets and drug repurposing opportunities by in silico analyses.

RESULTS

In addition to the major histocompatibility complex locus, we identified 15 genome-wide significant loci shared between at least 2 JIA subtypes, including 10 novel loci. Functional annotation indicated that candidate genes at these loci were expressed in diverse immune cell types.

CONCLUSION

This study identified novel genetic loci shared by JIA subtypes. Our findings identified candidate mechanisms underlying JIA subtypes and candidate targets with drug repurposing opportunities for JIA treatment.

Comparison of the outcomes between early and late anti-tumor necrosis factor therapy in patients with enthesitis-related subcategory of juvenile idiopathic arthritis: a multi-center study in Southeast Asia

BACKGROUND

Little is known about the impact of delayed initiation of anti-tumor necrosis factor (TNF) therapy in patients with enthesitis-related arthritis (ERA). Here, we compared the impact of delayed treatment on disease outcomes of ERA patients in Southeast Asia.

RESEARCH DESIGN AND METHODS

This retrospective study enrolled 149 ERA patients from Thailand and Singapore. Early (e-aTNF) and late (l-aTNF) treatment groups received anti-TNF therapy starting at ≤6 months and >6 months, respectively, after diagnosis. Outcomes included mean differences in disease activity parameters, Juvenile Spondyloarthritis Disease Activity (JSpADA) score, Juvenile Arthritis Diseases Activity (JADAS)-10 score, and American College of Rheumatology Pediatric (ACR Pedi) criteria, and the frequency of clinically inactive disease and first flare event.

RESULTS

The mean changes in JSpADA (p = 0.002) and JADAS-10 (p < 0.001) scores over time were significantly higher in the e-aTNF group than in the l-aTNF group. A significantly higher proportion of patients in the e-aTNF group than l-aTNF group satisfied ACR Pedi 100 criteria at 2 years (p = 0.042). All other long-term outcomes were not significantly different between the groups.

CONCLUSIONS

Although early anti-TNF treatment improved disease activity parameters somewhat better than delayed anti-TNF therapy, there was no significant difference in long-term outcomes.

Enthesitis-related arthritis: monitoring and specific tools

OBJECTIVES

In this article, the authors aimed to review the different tools used in the monitoring of enthesitis-related arthritis.

SOURCES

The authors performed a literature review on PubMed, Google Scholar, and Scopus databases. The dataset included the original research and the reviews including patients with enthesitis-related arthritis or juvenile spondylarthritis up to October 2020.

SUMMARY OF FINDING

Enthesitis-related arthritis is a category of juvenile idiopathic arthritis. It is characterized by the presence of enthesitis, peripheral arthritis, as well as axial involvement. The only validated tool for disease activity measurement in juvenile idiopathic arthritis is the Disease Activity Score: It has proven its reliability and sensitivity. Nevertheless, due to an absence of validated evaluation tools, the extent of functional impairment, as well as the children and parents' perception of the disease, could not be objectively perceived. Despite the great progress in the field of imaging modalities, the role they play in the evaluation of disease activity is still controversial. This is partially due to the lack of validated scoring systems.

CONCLUSIONS

Further work is still required to standardize the monitoring strategy and validate the outcome measures in enthesitis-related arthritis.

B Cells on the Stage of Inflammation in Juvenile Idiopathic Arthritis: Leading or Supporting Actors in Disease Pathogenesis?

Juvenile idiopathic arthritis (JIA) is a term that collectively refers to a group of chronic childhood arthritides, which together constitute the most common rheumatic condition in children. The International League of Associations for Rheumatology (ILAR) criteria define seven categories of JIA: oligoarticular, polyarticular rheumatoid factor (RF) negative (RF-), polyarticular RF positive (RF+), systemic, enthesitis-related arthritis, psoriatic arthritis, and undifferentiated arthritis. The ILAR classification includes persistent and extended oligoarthritis as subcategories of oligoarticular JIA, but not as distinct categories. JIA is characterized by a chronic inflammatory process affecting the synovia that begins before the age of 16 and persists at least 6 weeks. If not treated, JIA can cause significant disability and loss of quality of life. Treatment of JIA is adjusted according to the severity of the disease as combinations of non-steroidal anti-inflammatory drugs (NSAIDs), synthetic and/ or biological disease modifying anti-rheumatic drugs (DMARDs). Although the disease etiology is unknown, disturbances in innate and adaptive immune responses have been implicated in JIA development. B cells may have important roles in JIA pathogenesis through autoantibody production, antigen presentation, cytokine release and/ or T cell activation. The study of B cells has not been extensively explored in JIA, but evidence from the literature suggests that B cells might have indeed a relevant role in JIA pathophysiology. The detection of autoantibodies such as antinuclear antibodies (ANA), RF and anti-citrullinated protein antibodies (ACPA) in JIA patients supports a breakdown in B cell tolerance. Furthermore, alterations in B cell subpopulations have been documented in peripheral blood and synovial fluid from JIA patients. In fact, altered B cell homeostasis, B cell differentiation and B cell hyperactivity have been described in JIA. Of note, B cell depletion therapy with rituximab has been shown to be an effective and well-tolerated treatment in children with JIA, which further supports B cell intervention in disease development.

Spondyloarthritides: Theories and beyond

Spondyloarthritides (SpA) are a family of interrelated rheumatic disorders with a typical disease onset ranging from childhood to middle age. If left untreated, they lead to a severe decrease in patients' quality of life. A succesfull treatment strategy starts with an accurate diagnosis which is achieved through careful analysis of medical symptoms. Classification criterias are used to this process and are updated on a regular basis. Although there is a lack of definite knowledge on the disease etiology of SpA, several studies have paved the way for understanding plausible risk factors and developing treatment strategies. The significant increase of HLA-B27 positivity in SpA patients makes it a strong candidate as a predisposing factor and several theories have been proposed to explain HLA-B27 driven disease progression. However, the presence of HLA-B27 negative patients underlines the presence of additional risk factors. The current treatment options for SpAs are Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), TNF inhibitors (TNFis), Disease-Modifying Anti-Rheumatic Drugs (DMARDs) and physiotherapy yet there are ongoing clinical trials. Anti IL17 drugs and targeted synthetic DMARDs such as JAK inhibitors are also emerging as treatment alternatives. This review discusses the current diagnosis criteria, treatment options and gives an overview of the previous findings and theories to clarify the possible contributors to SpA pathogenesis with a focus on Ankylosing Spondylitis (AS) and enthesitis-related arthritis (ERA).

Enthesitis-related arthritis and spondylarthritis: the same disease or disparate entities?

OBJECTIVES

The aim of this study is to compare the clinical features, disease activity and physical impairment, between enthesitis-related arthritis, adult and late-onset spondylarthritis in Tunisian patients.

METHODS

This study included 190 patients divided into three groups according to their age at the onset of symptoms: ERA (onset of symptoms ≤ 16 years of age), AOSpA (16 < onset of symptoms < 50 years of age) and LOSpA (onset of symptoms ≥ 50 years of age). AOSpA and LOSpA patients fulfilled the ASAS criteria for SpA. Whereas, ERA patients were classified according to the ILAR criteria.

RESULTS

Among 190 patients, 21% had ERA, 70.5% had AOSpA, and 8.5% had LOSpA. There were no differences in gender ratio between ERA and AOSpA groups. Regarding the clinical presentation, ERA and LOSpA groups had more peripheral symptoms than AOSpA in whom the axial manifestation pattern continued throughout the course of the disease. HLA-B27 was more associated with ERA (p = 0,007). Extra-articular manifestations were more observed in the ERA group (p = 0.004). Disease activity, functional status and anthropometric parameters were similar between groups. Nevertheless, health-related quality-of-life assessed by ASQoL and SF-36 scores were better in the AOSpA group but with no significant differences. Regarding the treatment option, methotrexate was widely used in the ERA group (p < 0.001).

CONCLUSION

ERA is characterized mainly by marked peripheral arthritis, more extra-articular manifestations, and a higher frequency of hip involvement.

Immunopathophysiology of Juvenile Spondyloarthritis (jSpA): The "Out of the Box" View on Epigenetics, Neuroendocrine Pathways and Role of the Macrophage Migration Inhibitory Factor (MIF)

Juvenile spondyloarthritis (jSpA) is a an umbrella term for heterogeneous group of related seronegative inflammatory disorders sharing common symptoms. Although it mainly affects children and adolescents, it often remains active during adulthood. Genetic and environmental factors are involved in its occurrence, although the exact underlying immunopathophysiology remains incompletely elucidated. Accumulated evidence suggests that, in affected patients, subclinical gut inflammation caused by intestinal dysbiosis, is pivotal to the future development of synovial-entheseal complex inflammation. While the predominant role of IL17/23 axis, TNF-α, and IL-7 in the pathophysiology of SpA, including jSpA, is firmly established, the role of the cytokine macrophage migration inhibitory factor (MIF) is generally overlooked. The purpose of this review is to discuss and emphasize the role of epigenetics, neuroendocrine pathways and the hypothalamic-pituitary (HPA) axis, and to propose a novel hypothesis of the role of decreased NLRP3 gene expression and possibly MIF in the early phases of jSpA development. The decreased NLRP3 gene expression in the latter, due to hypomethylation of promotor site, is (one of) the cause for inflammasome malfunction leading to gut dysbiosis observed in patients with early jSpA. In addition, we highlight the role of MIF in the complex innate, adaptive cellular and main effector cytokine network, Finally, since treatment of advanced bone pathology in SpA remains an unmet clinical need, I suggest possible new drug targets with the aim to ultimately improve treatment efficacy and long-term outcome of jSpA patients.

Juvenile idiopathic arthritis: from aetiopathogenesis to therapeutic approaches

Juvenile idiopathic arthritis (JIA) is the most common paediatric rheumatological disorder and is classified by subtype according to International League of Associations for Rheumatology criteria. Depending on the number of joints affected, presence of extra-articular manifestations, systemic symptoms, serology and genetic factors, JIA is divided into oligoarticular, polyarticular, systemic, psoriatic, enthesitis-related and undifferentiated arthritis. This review provides an overview of advances in understanding of JIA pathogenesis focusing on aetiology, histopathology, immunological changes associated with disease activity, and best treatment options. Greater understanding of JIA as a collective of complex inflammatory diseases is discussed within the context of therapeutic interventions, including traditional non-biologic and up-to-date biologic disease-modifying anti-rheumatic drugs. Whilst the advent of advanced therapeutics has improved clinical outcomes, a considerable number of patients remain unresponsive to treatment, emphasising the need for further understanding of disease progression and remission to support stratification of patients to treatment pathways.

Hip involvement in children with enthesitis related arthritis (ERA) is associated with poor outcomes in adulthood

Background

The data on long-term outcome in enthesitis-related arthritis (ERA), the commonest category of JIA in India, is scant. Thus, we studied outcomes of ERA in a resource-constrained setting.

Methods

Patients with ERA (ILAR classification) (≥ 5 years of disease and ≥ 18 years) were included. Data on clinical features, Bath indices (BASMI, BASDAI, BASFI), ASDAS, and health assessment questionnaire-disability index (HAQ-DI) was collected. X-ray pelvis including hips was obtained and compared with baseline X-ray for progression of sacroiliitis and hip arthritis. Fulfillment of adult criteria of spondyloarthropathy (SpA) were also assessed.

Results

Seventy-three 73 patients (72 males) of median age 20 (18–23) years and disease duration 8 (5.5–11) years were recruited. There was delay in diagnosis of 4 (1.75–6) years. Thirty-nine (53%) had BASDAI ≥ 4 and 63 (91%) had ASDAS-CRP > 1.3. Two-third (60%) had functional disability (HAQ-DI ≥ 0.5). Poor outcome (BASDAI ≥ 4, ASDAS > 2.1, BASFI > 0.9, or HAQ-DI ≥ 0.5) was seen in three-fourths (n = 56.76%) of patients and was associated with hip involvement, HLA-B27 positivity, and fulfillment of axial ASAS criteria. Sixty-seven (91%) patients fulfilled axial ASAS criteria, while 71 (97%) fulfilled peripheral ASAS criteria.

Overall, 81% had X-ray sacroiliitis and 37% had hip involvement. Nearly half (46.6%) and one-fourths (25%) of the patients had X-ray sacroiliitis and hip arthritis progression, respectively. Those with X-ray hip arthritis had longer delay in diagnosis (6 vs 3 years), higher Bath indices, ASDAS, and HAQ-DI. Hip arthritis correlated with radiological sacroiliitis (r = 0.301). Fulfillment of modified NY criteria was seen more often in patients with hip arthritis (95 vs 63%; p < 0.002).

Conclusion

Most ERA patients had active disease in adulthood. Hip involvement, axial involvement, and HLA-B27 positivity were predictors of poor outcome.

Key Points • Almost 90% of adults with ERA had active disease even after 8 years of disease. • Poor outcomes were seen in three-fourths of patients and hip involvement, presence of HLA B27, and axial involvement were the predictors of poor outcome.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10067-021-05807-3.

Enthesitis Related Arthritis in a Longitudinal Southeast Asian Registry: High Prevalence of HLA-B27, Different Sacroiliitis Risk Factors and Less Common Drug-Free Remission

Objective. To describe the clinical characteristics, predictors and treatment of children with Enthesitis Related Arthritis (ERA) in a Singapore longitudinal cohort over 11 years. Methods. ERA patients were recruited from our registry (2009–2019). Nonparametric descriptive statistics including median (interquartile range, IQR) were used to describe data. Kaplan–Meier survival and logistic/Cox regression analyses were used to estimate the probabilities and determine predictors of clinical variables, respectively. The significance level was set at <0.05. Results. One hundred and forty-six ERA patients (87% male, 82% Chinese) were included. Median onset age was 11.9 years (IQR 9.4–14.0) and median disease duration was 4.9 years (IQR 2.6–8.3). Family history of Human Leukocyte Antigen (HLA)-B27 associated diseases was positive in 7.5%. Acute uveitis occurred in 3.4%. Oligoarthritis was present in 89.7%. Hip, knee and ankle joints were among the most common joints involved. One-fourth had enthesitis at diagnosis (Achilles tendon entheses, 82.9%). Sacroiliitis occurred in 61%. Probabilities of sacroiliitis development were 0.364, 0.448 and 0.578 at 1, 2 and 5 years after onset, respectively. Negative HLA-B27, female, older age at onset and hip arthritis at diagnosis were associated with shorter time for sacroiliitis development (p = 0.001–0.049). Methotrexate (MTX) remained the most common disease modifying anti-rheumatic drug (DMARD) used (77.4%). However, 77.9% required anti-TNF (aTNF) therapy secondary to MTX failure. Among MTX-treated sacroiliitis patients, 85.3% failed, requiring aTNF, as compared to 63.2%patients without axial disease. Longer duration to diagnosis (p = 0.038) and MTX use (p = 0.007) predicted aTNF therapy. None had joint deformity. Conclusions. This study underscores differences in ERA clinical characteristics, predictors and treatment responses. Our ERA population had many unique findings but good functional outcomes.

Capturing the enthesitis related arthritis contemporary profile of Caucasian patients in the era of biologics

To describe the profile of Enthesitis Related Arthritis' (ERA) patients, in the era of biologic DMARDs (bDMARDs). This retrospective cohort study included patients with ERA monitored on a 3-month schedule for at least 1 year. Their metric assessment included the disease status and damage by applying the contemporary tools clinical-Juvenile Arthritis Disease Activity Score (c-JADAS), Juvenile Spondyloarthritis Disease Activity Index (JSpADA), clinical remission (CR) on/off medication and Juvenile Arthritis Damage Index (JADI). 43 patients (males 26) were enrolled, with a mean disease onset of 10.75 years. Median lag time from diagnosis to bDMARDs was 8.5 months. Patients with sacroiliitis received earlier bDMARDs (hazard ratio, HR 3.26). 36/43 patients achieved CR on medication (median time 11 months), which was correlated with compliance (HR: 3.62). The percentage of CR in patients with or without sacroiliitis was 35% and 63% respectively (p = 0.02). Twenty patients (47%) experienced a flare following CR (75%). The median flare-free survival following CR on/off medication was 42 and 34 months, respectively. At the last evaluation, both median baseline cJADAS and JSpADA dropped to 0, 13/43 patients had a persistent disease activity, while 17/43 and 13/43 patients were in CR on/off medication, respectively. The median patient percentage of CR was 54% and no patient had a JADI > 0. Increased lag time to bDMARDs was associated with increased CR (Odds ratio: 1.48). Early administration of bDMARDs and compliance improved long-term outcome of ERA. Sacroiliitis was a negative prognostic factor with an increased need for bDMARDs and diminished rates of CR.

Enthesitis-related Arthritis: Prevalence and Complications of Associated Uveitis in Children and Adolescents From a Population-based Nationwide Study in Germany

Objective.

Enthesitis-related arthritis (ERA) represents a subgroup of juvenile idiopathic arthritis (JIA) that is regularly accompanied by anterior uveitis. This study describes the prevalence and characteristics of ERA-related uveitis.

Methods.

Cross-sectional data from the National Pediatric Rheumatological Database (NPRD) were used to characterize ERA-related uveitis (ERA-U). In addition to sociodemographic variables, we documented the occurrence of uveitis and course of disease, including symptoms, visual acuity, and complications, as well as JIA characteristics such as disease activity (Juvenile Arthritis Disease Activity Score 10), functional ability (Childhood Health Assessment Questionnaire score), laboratory variables, and treatment.

Results.

In the years from 2002 to 2014, there were 3778 (15.2%) of a total of 24,841 JIA patients recorded in the NPRD who had ERA, and 280 (7.4%) of them had developed uveitis. Detailed ophthalmological documentation by a uveitis add-on module was available for 22.9% of these patients. Uveitis onset was acutely symptomatic in 63% of patients. Patients with uveitis were more frequently male, HLA-B27–positive, younger at ERA onset, and they had higher erythrocyte sedimentation rate values at first uveitis documentation than those without uveitis. Uveitis was diagnosed at a mean age of 11.5 (± 3.9) years (50% within 2 years after ERA onset). Systemic treatment with corticosteroids and synthetic and biologic disease-modifying antirheumatic drugs was associated with a (not significantly) lower risk of developing uveitis.

Conclusion.

The course of disease in ERA-U patients is frequently similar to HLA-B27–associated uveitis in adults; however, a subgroup of patients presents with asymptomatic uveitis.

Musculoskeletal ultrasound in children: Current state and future directions

Juvenile idiopathic arthritis (JIA) is a heterogeneous group of chronic inflammatory arthritides that if inadequately treated, may be associated with chronic disability and deformity. Early diagnosis and treatment initiation is essential in the management of patients with JIA. Conventional means of evaluation of disease presence, disease activity and response to therapy including physical exam, labs and x-rays are at times limited and may be insufficient in making an accurate assessment. Musculoskeletal ultrasound (MSUS) is a well-established modality that is patient and family-friendly, non-invasive, does not require sedation and can be performed at the bedside in real-time. MSUS offers information that cannot be attained by standard outcome measures, and may help to advance both diagnosis and treatment of patients with JIA ultimately improving patient outcomes. This review explores the background of MSUS and the current evidence to support its potential role as a diagnostic, disease activity monitoring and interventional tool.

Patients with enthesitis related arthritis show similar monocyte function pattern as seen in adult axial spondyloarthropathy

BACKGROUND

Axial SpA and Enthesitis related arthritis (ERA) patients show strong HLA-B27 association, gut dysbiosis, high toll like receptor (TLR)2 and 4 expression on monocytes, pro-inflammatory cytokine production and elevated levels of TLR4 endogenous ligands [tenascin-c (TNC) and myeloid related protein (MRP)8/14] in serum. Hence, we aimed to understand if these diseases have similar or different monocyte response.

METHODS

Fifty adult axial SpA, 52 ERA patients and 25 healthy controls (HC) were enrolled. Cytokine-producing monocyte frequency before and after stimulation with lipopolysaccharide (LPS), peptidoglycan (PG), TNC or MRP8 were measured in whole blood (WB) and synovial fluid mononuclear cells (SFMC) by flow cytometry. Also, IL-6, TNF, MMP3, TNC and MRP8/14 levels were measured in unstimulated and TLR ligand stimulated WB cultures supernatant by ELISA. Finally, the mRNA expression levels of TNF and IL-6 were measured post stimulation with LPS, TNC and MRP8.

RESULTS

At baseline, ERA and axial SpA patients showed similar TNF-α producing monocyte frequency which was higher than HC. MRP8 simulation led to increased TNF-α producing monocyte frequency in ERA than axial SpA. TNC and MRP8 stimulation led to similar IL-6 producing monocyte frequency in axial SpA and ERA patients. Baseline TNF and IL-6 producing monocyte frequency also modestly correlated with disease activity scores. TNF and IL-6 producing monocyte frequency increased in response to TLR stimulation in SFMC from both patients. In culture supernatants, axial SpA and ERA patients showed similar TNF production at baseline. MRP8 and TNC stimulation led to higher TNF production from ERA. Baseline IL-6 and MMP3 production was higher in ERA while TLR stimulation led to similar IL-6 and MMP3 production from axial SpA and ERA. TNC stimulation led to higher MMP3 production in ERA. mRNA expression in response to TLR stimulation was observed to be similar in axial SpA and ERA. TNC production was higher in ERA at baseline, while MRP8/14 production was higher in axial SpA than ERA post stimulation.

CONCLUSION

ERA patients have similar monocyte response to exogenous and endogenous TLR ligands as patients with axial SpA. This suggests that differences between pediatric and adult-onset SpA are minimal and they may have a common pathogenesis.