Hemophagocytic lymphohistiocytosis and macrophage activation syndrome: two rare sides of the same devastating coin.

Hemophagocytic lymphohistiocytosis (HLH) is a rare genetic hyperinflammatory syndrome that occurs early in life. Macrophage activation syndrome (MAS) usually refers to a secondary form of HLH associated with autoimmunity, although there are other causes of secondary HLH, such as infections and malignancy. In this article, we reviewed the concepts, epidemiology, clinical and laboratory features, diagnosis, differential diagnosis, prognosis, and treatment of HLH and MAS. We also reviewed the presence of MAS in the most common autoimmune diseases that affect children. Both are severe diseases that require prompt diagnosis and treatment to avoid morbidity and mortality.

A Case of Adult-onset Still's Disease (AOSD) with Gastrointestinal Lesions.

A 51-year-old woman with fever was admitted to our hospital. A computed tomography (CT) scan showed thickened colonic walls. Colonoscopy revealed erosion in the ileum and colon. Adult-onset Still's disease (AOSD) was diagnosed due to a subsequent sore throat and skin rash. Following AOSD treatment, methylprednisolone pulse therapy, followed by prednisolone and cyclosporine, was initiated. Despite achieving a temporary improvement, relapse occurred with fever, abdominal pain, with worsening CT and endoscopic findings. The reappearance of a skin rash confirmed an exacerbation of AOSD. Tocilizumab treatment alleviated the symptoms and improved the endoscopic findings. Considering their correlation with the symptoms and endoscopic findings, the observed gastrointestinal lesions may be linked to AOSD.

Relationships among gut microbiota, plasma metabolites, and juvenile idiopathic arthritis: a mediation Mendelian randomization study.

Objective: The objective of this study is to investigate the causal relationship between gut microbiota and juvenile idiopathic arthritis, and to identify and quantify the potential role of plasma metabolites as mediators. Methods: Using summary-level data from genome-wide association studies, a two-sample Mendelian randomization was conducted involving 131 gut microbiota genus, 1,400 plasma metabolites, and juvenile idiopathic arthritis. Additionally, a two-step approach was employed to quantify the proportion of the effect of gut microbiota on juvenile idiopathic arthritis mediated by plasma metabolites. Effect estimation primarily utilized Inverse Variance Weighting, with further validation using Bayesian weighted Mendelian randomization. Results: In our MR analysis, a positive correlation was observed between Rikenellaceae and the risk of juvenile idiopathic arthritis, while Dorea showed a negative correlation with juvenile idiopathic arthritis risk. Mediation analysis indicated that Furaneol sulfate levels acted as a mediator between Dorea and juvenile idiopathic arthritis, with an indirect effect proportion of 19.94, 95% CI [8.86-31.03%]. Conclusion: Our study confirms a causal relationship between specific microbial genus and juvenile idiopathic arthritis, and computes the proportion of the effect mediated by plasma metabolites, offering novel insights for clinical interventions in juvenile idiopathic arthritis.

Influenza vaccine uptake in juvenile idiopathic arthritis: a multi-centre cross-sectional study.

While most countries provide safe and effective influenza vaccines for at-risk groups, influenza vaccine coverage among children with rheumatic diseases remains uncertain. This study investigated influenza vaccination rates in children with juvenile idiopathic arthritis (JIA) during the 2019-2020 season and assessed the knowledge and attitudes of caregivers of children with JIA regarding influenza vaccination. The secondary aims were to identify barriers to vaccination and explore strategies to improve vaccination rates. A multi-centre, cross-sectional anonymous survey was conducted in 7 countries during the 2019-2020 influenza season to assess the uptake history of influenza vaccination. Among 287 participants, only 87 (30%) children with JIA received the influenza vaccine during the 2019-2020 season. Children who were more likely to be vaccinated were those with systemic juvenile idiopathic arthritis (sJIA), a history of previous vaccination and those aware of the vaccination recommendations. Conversely, children who previously experienced adverse vaccine-related events reported the lowest uptake. The primary reason for non-vaccination was lack of awareness about the necessity of influenza vaccination.  Conclusion: Despite variations among countries, the uptake of influenza vaccines remains low in children with JIA. Improving awareness among families about the importance of influenza vaccination may increase vaccination rates in children with rheumatic diseases. What is Known: • Rheumatic children are at increased risk for influenza infection due to immunosuppressive therapy and immune dysregulation. • Influenza vaccine is formally recommended to children with rheumatic diseases. What is New: • This multicentre study showed that influenza vaccine uptake rates remain suboptimal among children with Juvenile Idiopathic Arthritis despite formal recommendations. • Factors like previous experience with vaccination and information provided by medical professionals via different ways play essential roles in increasing vaccination rates and can contribute to improved health outcomes for these vulnerable children.

The Juvenile Arthritis Quality of Life Questionnaire in patients with juvenile idiopathic arthritis: Turkish version, validity, and reliability study.

INTRODUCTION: This study aimed to assess the cultural adaptation, validity, and reliability of the Turkish version of the Juvenile Arthritis Quality of Life Questionnaire (JAQQ) in patients with juvenile idiopathic arthritis (JIA). METHODS: A total of 100 JIA patients (64% female), aged 9 to 18 years, participated in the study conducted at a tertiary care university hospital. The JAQQ was culturally adapted through a rigorous translation process and administered alongside established measures, including the Childhood Health Assessment Questionnaire (CHAQ), Juvenile Arthritis Biopsychosocial Questionnaire (JABQ), and Children's Depression Inventory (CDI). Validity and reliability were evaluated using Spearman's correlation coefficients, Cronbach's alpha, intraclass correlation coefficient (ICC), standard error of the mean (SEM), and minimal detectable change (MDC). RESULTS: The Turkish version of JAQQ exhibited high convergent validity, correlating significantly with CHAQ, JABQ, and CDI. No floor or ceiling effects were observed in the total JAQQ score, indicating a balanced assessment. Internal consistency was excellent (Cronbach's α = 0.948), and test-retest reliability was satisfactory (ICC = 0.913). SEM and MDC95 values were 0.357 and 0.99, respectively. CONCLUSIONS: The Turkish adaptation of JAQQ emerges as a valid and reliable instrument for comprehensively assessing the health-related quality of life in children and adolescents diagnosed with JIA. The questionnaire's robust psychometric properties, coupled with distinctive features like individualized assessment, highlight its potential as a valuable tool for both clinical assessment and scientific research in the field of pediatric rheumatology. Key Points • The Juvenile Arthritis Quality of Life Questionnaire (JAQQ) is an important scale that evaluates the quality of life of children with Juvenile Idiopathic Arthritis (JIA). • JAQQ is known and used in the field of pediatric rheumatology in Turkey, but its Turkish adaptation has not been made before. • Our study includes 100 JIA patients aged between 9 and 18 years and shows that the Turkish version of JAQQ is valid and reliable in measuring the quality of life of these children. • This research contributes to the accurate assessment of the quality of life in Turkish children diagnosed with JIA, providing valuable insights for both clinical and scientific studies.

Treatment of Posterior Hip Dislocation due to Juvenile Idiopathic Arthritis. Report of Two Cases.

Introduction: Juvenile idiopathic arthritis ( JIA) is a persistent autoimmune-inflammatory disease that affects children younger than 16. Aggressive synovitis of the hip may cause joint destruction, hip protrusion, erosion, pseudosubluxation, dysplasia, and osteoarthritis. Subluxation of the hip had been reported previously. However, dislocation of the hip in JIA is an extremely rare situation, and only two cases have been reported up to date. Reduction of the dislocated hip has to be performed in any way. However, there is no algorithm to be followed for the treatment of hip dislocations caused by JIA. Case Presentation: In this study, we presented two cases of hip dislocation caused by JIA.Case 1: An 11-year-old boy had JIA and chronic recurrent multifocal osteomyelitis (CRMO). X-rays and computed tomography (CT) revealed a posterior dislocation of the left hip. An urgent operation was planned for the reduction of the hip. Avascular necrosis, dysplasia, or erosions were not evident at the last follow-up.Case 2: An 11-year-old girl was referred to the hospital with excessive left hip pain starting 24 h ago. A limited synovectomy with joint irrigation was performed. However, pathological examination of the synovium showed chronic inflammation consistent with JIA. On the post-operative 10th day, the patient was consulted for an increase in hip pain and deformity of the left hip. X-rays and MRI revealed posterior dislocation of the left hip with synovial hypertrophy. An urgent operation was planned. The hip could be reduced under anesthesia with mild traction, and a pelvipedal cast was applied only for 3 weeks. Avascular necrosis, dysplasia, destruction, or erosions were not evident at the last follow-up. Conclusion: For early diagnosed patient reduction under anesthesia and medial soft-tissue contracture release; for late diagnosed patient medial soft-tissue contracture release, capsulotomy and synovectomy were effective to prevent destruction and early degenerative changes of the hip joint for treatment of dislocation caused by JIA.

Reliability assessment of the OMERACT whole-body magnetic resonance imaging scoring system for juvenile idiopathic arthritis.

Inter-reader reliability of a new scoring system for evaluating joint inflammation and enthesitis in whole body MRI (WBMRI) in juvenile idiopathic arthritis was tested. The scoring system grades 732 item-region combinations of bone marrow and soft tissue changes for commonly involved joints and entheseal sites. Five radiologists rated 17 WBMRI scans through an online rating platform. Item-wise reliability was calculated for 117 items with non-zero scores in >10 % of readings. Interquartile ranges of the five-reader Kappa reliability coefficients were 0.58-0.73 (range: 0.36-0.88) for the joints, 0.65-0.81 (range: 0.39-0.95) for the entheses, and 0.62-0.75 (range: 0.60-0.76) for chronic nonbacterial osteomyelitis-like lesions.

Asymptomatic intraspinal epidermoid cyst in a 7-year-old male with juvenile idiopathic arthritis identified by an advanced physiotherapist practitioner: a case report.

BACKGROUND: Pediatric intraspinal epidermoid cysts are rare with potential to cause life-altering outcomes if not addressed. Reports to date describe symptomatic presentations including loss of bladder or bowel function and motor and sensory losses. This case report identifies the diagnostic challenge of an asymptomatic intraspinal epidermoid cyst in the cauda equina region presenting in a 7-year-old male with juvenile idiopathic arthritis (JIA). DIAGNOSIS: An advanced physiotherapist practitioner assessed and diagnosed a previously healthy 7-year-old-male of South Asian descent with JIA based on persistent knee joint effusions. Complicating factors delayed the investigation of abnormal functional movement patterns, spinal and hip rigidity and severe restriction of straight leg raise, all atypical for JIA. Further delaying the diagnosis was the lack of subjective complaints including no pain, no reported functional deficits, and no neurologic symptoms. A spinal MRI investigation 10-months from initial appointment identified intraspinal epidermoid cysts occupying the cauda equina region requiring urgent referral to neurosurgery. DISCUSSION: Clinical characteristics and pattern recognition are essential for diagnosing spinal conditions in pediatric populations. Diagnostic challenges present in this case included co-morbidity (JIA), a severe adverse reaction to treatment, a lack of subjective complaints and a very low prevalence of intraspinal epidermoid cysts. IMPACT STATEMENTS: Early signs of pediatric asymptomatic intraspinal epidermoid cysts included abnormal functional movement patterns, rigidity of spine, severely limited straight leg raise and hip flexion without pain. Advanced physiotherapist practitioners can be integral to pediatric rheumatology teams considering their basic knowledge in musculoskeletal examination and functional mobility assessment when identifying rare spinal conditions that present within the complex context of rheumatic diseases.

Provider assessment of the temporomandibular joint in Juvenile idiopathic arthritis: a retrospective analysis from the CARRA database.

BACKGROUND: Temporomandibular joint (TMJ) involvement is an often underrecognized complication of juvenile idiopathic arthritis (JIA) that can cause decreased mandibular growth, altered facial morphology, and orofacial pain. It is estimated that the TMJ is affected in 30-45% of children with JIA. Standardized physical examination and imaging evaluations are important in accurately assessing active TMJ arthritis and sequalae. Little is known about the rate at which providers evaluate TMJ involvement in their clinical practice. METHODS: Data were obtained from the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry. Data fields related to assessment for TMJ arthritis were added in 2019. Patients were included in the study if they had a diagnosis of JIA and had data recorded between January 2020 and August 2021. Standard descriptive statistics were used to describe demographic and clinical features. RESULTS: A total of 17,761 visits were reviewed for a total of 7473 patients with JIA. A total of 52.7% of patients had maximal mouth opening (MMO) recorded as finger breadths or total incisal distance (TID). Only 8% had TID measured. A total of 5.0% had MRI with contrast performed. A total of 939 patients had a diagnosis of TMJ arthritis. Of these, 28.5% had an MRI documented, 83% had an MMO documented, and 40% had TID measured. Few patient-level characteristics were statistically related to having MMO assessed. MRI was more likely to be obtained in older and in female patients. MMO was recorded at a given visit > 80% of the time at 17 sites, and it was recorded < 1% of the time at 8 sites. MRIs were infrequently performed at all sites, with 27 sites having no MRIs obtained and only 7 sites having an MRI obtained at > 10% of visits. CONCLUSIONS: MMO is not consistently measured in patients with JIA, and it is rarely measured quantitatively. Similarly, TMJ MRIs are rarely obtained in patients with JIA. Site of care is more associated with TMJ assessments than patient-level characteristics. These data suggest that provider education is needed to improve the assessment of the TMJ in patients with JIA to enable earlier recognition and prevent long-term complications.

Predictors of disease course in systemic juvenile idiopathic arthritis.

PURPOSE: To identify potential predictors of the disease course of systemic juvenile idiopathic arthritis (sJIA) at the time of diagnosis. METHODS: This retrospective observational study was conducted in patients diagnosed with sJIA in our hospital between April 2009 and October 2023. The relationship between the disease course of sJIA patients and demographic, clinical, laboratory findings and complications were analyzed. RESULTS: Of the 51 patients diagnosed with sJIA, 26 (51%) patients had monocyclic, 7 (13.7%) polycyclic and 18 (35.2%) persistent disease course. 3 (5.8%) patients had a persistent disease course with persistent arthritis developed flares with systemic manifestations during follow-up. The presence of arthritis, polyarticular involvement, and hip involvement at the time of diagnosis were associated with persistent disease course (p=0.009, p=0.003, p=0.003). Serositis and higher white blood cell and neutrophil counts at the time of diagnosis were associated with a monocyclic disease course (p=0.034, p=0.002, p=0.008). However, no significant correlation was found between macrophage activation syndrome (MAS) and disease course (p=1). CONCLUSIONS: Systemic JIA patients with polyarthritis and hip involvement at disease onset may develop a persistent course. Although MAS is an important complication of sJIA, its effect on the course of the disease was not found in this study.

Anxiety and depression symptoms in adolescents and young adults with juvenile idiopathic arthritis: results of an outpatient screening.

BACKGROUND: Previous studies have shown that growing up with rheumatic conditions can fuel dissatisfaction and psychological distress, which in turn affects disease self-management and treatment adherence. Primary objective of this study was to estimate the prevalence of anxiety and depression symptoms in adolescents and young adults (AYA) with juvenile idiopathic arthritis (JIA) and to identify correlates of conspicuous screening results. METHODS: Initiated as part of the COACH multicenter observational study, outpatients aged 12 to 21 years participating in the National Pediatric Rheumatological Database (NPRD) were prospectively screened for mental health using the Patient Health Questionnaire-9 (PHQ-9) and the Generalised Anxiety Disorder Scale-7 (GAD-7). RESULTS: Data from 1,150 adolescents with JIA (mean age 15.6 ± 2.2 years; mean disease duration 7.2 ± 4.9 years, 69% female, 43% oligoarthritis, 26% polyarthritis) were analysed. Overall, 32.7% (n = 316) of AYA showed conspicuous screening results, of whom 30.4% reported clinically relevant suicidal or self-harm thoughts. About 19% of screened patients showed moderate to severe depressive or anxious symptoms. AYA with conspicuous screening results were older (15.8 vs. 15.2 years; p < 0.0001), more often female (81% vs. 64%; p < 0.0001) and more often overweight (25% vs. 17%; p = 0.006). They had higher disease activity (physician global assessment on NRS 0-10; 1.7 vs. 1.2; p < 0.0001), more functional limitations (CHAQ; 0.44 vs. 0.14; <0.0001) and rated their health status worse (NRS 0-10; 3.5 vs. 1.8; p < 0.0001) than AYA with inconspicuous screening results. Females (OR 2.33 [CI 1.53-3.56]; p < 0.0001), older age (OR 1.09 [CI 1.01-1.18]; p = 0.026), patients with more functional limitations (OR 3.36 [CI 1.98-5.72]; p < 0.0001), and patients with worse subjective health status (OR 1.17 [CI 1.07-1.27]; p < 0.0001) were more likely to have a conspicuous screening result. Regular sports participation was associated with a lower likelihood of conspicuous screening result (OR 0.69 [CI 0.49-0.98]; p = 0.039). CONCLUSIONS: A large-scale outpatient screening of AYA with JIA in Germany shows a high prevalence of anxiety and depression symptoms. The need for routine screening for early detection of mental health problems became apparent.

Does sacroiliitis is a mandatory criterion for enthesitis-related arthritis diagnosis? / ¿La sacroilitis es un criterio obligatorio para el diagnóstico de artritis relacionada con entesitis?

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.(AU)

Introducción y objetivos: La sensibilidad y especificidad de la resonancia magnética parecen estar menos estudiadas en la artritis relacionada con entesitis (ERA). Nuestro objetivo era determinar la capacidad de la resonancia magnética de la articulación sacroilíaca para diagnosticar pacientes con ERA. Materiales y métodos: Realizamos un estudio retrospectivo que incluyó a 44 pacientes con artritis idiopática juvenil (AIJ). A cada paciente se le realizó una resonancia magnética de la articulación sacroilíaca. Dividimos a los pacientes en dos grupos: G1: pacientes con ERA y G2: pacientes con subtipo no ERA. Resultados: Se observó ERA en 61% de los casos. Las articulaciones sacroilíacas resultaron dolorosas en 15 pacientes (34%). La resonancia magnética fue normal en 25 pacientes (57%) (G1:11 vs. G2:14) y mostró edema de médula ósea en las articulaciones sacroilíacas en 19 pacientes (34%) (G1=16 vs. G2=3, p=0,005). La sensibilidad y especificidad de la resonancia magnética de articulaciones sacroilíacas en el diagnóstico de ERA fueron de 61,54 y 82,35%, respectivamente. Los valores predictivos positivos y negativos fueron 84,21 y 58,33%, respectivamente. Además, el dolor en la articulación sacroilíaca en el examen clínico fue capaz de predecir el edema del hueso sacroilíaco en la resonancia magnética con un odds ratio de 6,8 (IC 95%: 1,68 a 28,09; p=0,006). Conclusión: Nuestro estudio demostró que la resonancia magnética de la articulación sacroilíaca tiene buena especificidad y valor predictivo positivo en el diagnóstico de pacientes con ERA entre pacientes con AIJ. Esto subraya la utilidad de la resonancia magnética de la articulación sacroilíaca en el diagnóstico temprano de pacientes con ERA.(AU)

Measuring synovial thickness on knee MRI in pediatric patients with arthritis: is contrast necessary?

BACKGROUND: The use of contrast-enhanced imaging has long been standard for magnetic resonance imaging (MRI) assessments of synovitis in juvenile idiopathic arthritis (JIA). However, advancements in MRI technology have allowed for reliable identification of synovium without contrast. OBJECTIVE: To assess the equivalence of unenhanced MRI with contrast-enhanced MRI in evaluating synovial thickness. MATERIALS AND METHODS: This is an institutional review board approved, retrospective study performed in a tertiary children's hospital. Pediatric JIA patients under 21 years old were included who underwent knee MRI scans (1.5 T or 3 T) without and with contrast between January 2012 and January 2022. Two radiologists independently measured synovial thickness at 6 knee sites on contrast-enhanced and unenhanced sequences. Numerical measurements and ordinal scores based on juvenile idiopathic arthritis magnetic resonance imaging scoring (JAMRIS) system were recorded, and tests of equivalence were conducted, as well as between-reader and within-reader reliability by concordance correlation coefficient (CCC). All tests were considered significant at the 5% level. RESULTS: A total of 38 studies from 35 patients (25 females, median age 14 years; interquartile range 7 to 15.7) were included. Equivalence was demonstrated at each of the 6 sites for both continuous measurements (P-values < 0.05) and ordinal scores (P-values < 0.05) based on the average over readers. Within-reader reliability was moderate to high (CCC 0.50-0.89), except for the cruciate ligaments site. Averaged over the 6 sites, reliability between readers was low for unenhanced (CCC 0.47, with 95% CI: [0.41, 0.53]) and moderate for contrast-enhanced (CCC 0.64, with 95% CI: [0.59, 0.69]) sequences. CONCLUSION: Unenhanced knee MRI is equivalent to contrast-enhanced MRI in assessment of synovial thickness using conventional MRI sequences. Contrast material helped improve inter-reader reliability.

Bone health and physical activity in adolescents with juvenile idiopathic arthritis: a cross-sectional case-control study.

BACKGROUND: Adolescents with juvenile idiopathic arthritis (JIA) tend to engage in less physical activity than their typically developing peers. Physical activity is essential for bone development and reduced physical activity may detrimentally effect bone health. Thus, we examined differences in total body bone mineral content (BMC) and areal bone mineral density (aBMD) between adolescents with JIA and adolescent controls without JIA. We also examined associations between moderate-to-vigorous physical activity (MVPA), lean mass, and bone outcomes. METHODS: Participants included 21 adolescents with JIA (14 females, 7 males) and 21 sex- and age-matched controls aged 10-20 years. Assessments included: height; weight; triple-single-leg-hop distance (TSLH); MVPA by accelerometry; and total body BMC, aBMD, and lean mass measured using dual X-ray absorptiometry. Height-adjusted z-scores were calculated for BMC and aBMD and used for all analyses. Multiple linear mixed effects models examined group differences in BMC and aBMD, adjusting for sex, maturity, MVPA, TSLH, and lean mass. Participants clusters, based on sex and age (within 18 months), were considered random effects. RESULTS: Adolescents with JIA had lower total body aBMD z-scores [ß (95% CI); -0.58 (-1.10 to -0.07), p = 0.03] and BMC z-scores [-0.47 (-0.91 to -0.03), p = 0.04] compared with controls. Mean daily MVPA was 22.0 min/day lower in adolescents with JIA than controls; however, MVPA was not associated with aBMD [-0.01 (-0.01 to 0.01), p = 0.32] or BMC [0.00 (-0.01 to 0.00), p = 0.39]. Lean mass was positively associated with aBMD [0.05 (0.01 to 0.09) g/cm2, p = 0.03] and BMC [0.06 (0.03 to 0.10) g, p < 0.001]. CONCLUSION: Adolescents with JIA had lower total body aBMD and BMC compared with sex- and age-matched controls without JIA. Group differences in bone outcomes were not associated with the lower MVPA participation of adolescents with JIA. Despite this, physical activity should still be encouraged as it promotes physical well-being.

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.

Measles-specific antibodies loss after a single dose of MMR vaccine in children with oligo-articular JIA on methotrexate treatment: a single-center case-controlled study.

Novel treatments have revolutionized the care and outcome of patients with juvenile idiopathic arthritis (JIA). Patients with rheumatic diseases are susceptible to infections, including vaccine preventable ones, due to waning immunity, failing immune system and immunosuppressive treatment received. However, data regarding long-term immunological memory and response to specific vaccines are limited. Assessment of the impact of methotrexate (MTX) treatment on measles-specific-IgG titers, in children with oligo-JIA previously vaccinated with Measles Mumps Rubella (MMR) vaccine (1 dose); by evaluating the persistence of antibodies produced after measles vaccination while on immunomodulating treatment at 0, 12 and 24 months. Single-center controlled study including 54 oligo-JIA patients and 26 healthy controls. Seroprotection rates and measles-specific-IgG titers were measured by ELISA and were expressed as GMCs (Geometric Mean Concentrations).The two groups had similar demographic characteristics, vaccination history and immunization status. Seroprotection rates were adequate for both groups. Nonetheless, measles GMCs were significantly lower in the oligo-JIA compared to the control group at one (p = 0.039) and two years' follow-up (p = 0.021). Children with oligo-JIA on MTX treatment appeared to have lower measles-specific-IgG titers. Further studies are required to assess the long-term immunity conveyed by immunizations given at an early stage in children with rheumatic diseases on synthetic Disease Modifying Antirheumatic Drugs (sDMARDs) and to assess the need for booster doses to subjects at risk.

Construction and validation of a machine learning model for the diagnosis of juvenile idiopathic arthritis based on fecal microbiota.

Purpose: Human gut microbiota has been shown to be significantly associated with various inflammatory diseases. Therefore, this study aimed to develop an excellent auxiliary tool for the diagnosis of juvenile idiopathic arthritis (JIA) based on fecal microbial biomarkers. Method: The fecal metagenomic sequencing data associated with JIA were extracted from NCBI, and the sequencing data were transformed into the relative abundance of microorganisms by professional data cleaning (KneadData, Trimmomatic and Bowtie2) and comparison software (Kraken2 and Bracken). After that, the fecal microbes with high abundance were extracted for subsequent analysis. The extracted fecal microbes were further screened by least absolute shrinkage and selection operator (LASSO) regression, and the selected fecal microbe biomarkers were used for model training. In this study, we constructed six different machine learning (ML) models, and then selected the best model for constructing a JIA diagnostic tool by comparing the performance of the models based on a combined consideration of area under receiver operating characteristic curve (AUC), accuracy, specificity, F1 score, calibration curves and clinical decision curves. In addition, to further explain the model, Permutation Importance analysis and Shapley Additive Explanations (SHAP) were performed to understand the contribution of each biomarker in the prediction process. Result: A total of 231 individuals were included in this study, including 203 JIA patients and Non-JIA individuals. In the analysis of diversity at the genus level, the alpha diversity represented by Shannon value was not significantly different between the two groups, while the belt diversity was slightly different. After selection by LASSO regression, 10 fecal microbe biomarkers were selected for model training. By comparing six different models, the XGB model showed the best performance, which average AUC, accuracy and F1 score were 0.976, 0.914 and 0.952, respectively, thus being used to construct the final JIA diagnosis model. Conclusion: A JIA diagnosis model based on XGB algorithm was constructed with excellent performance, which may assist physicians in early detection of JIA patients and improve the prognosis of JIA patients.

Level and correlates of physical activity among children and adolescents with juvenile idiopathic arthritis compared to controls: results from a German nationwide prospective observational cohort study.

BACKGROUND: Physical active lifestyles are essential throughout growth and maturation and may offer potential preventive and therapeutic benefit in patients with juvenile idiopathic arthritis (JIA). Insufficient physical activity (PA), in contrast, can lead to aggravation of disease-related symptoms. This study aimed to i) examine PA levels in children and adolescents with JIA compared to general population controls and ii) investigate correlates of pronounced physical inactivity in order to identify risk groups for sedentary behaviour. METHODS: Data from children and adolescents with JIA and population controls aged 3 to 17 years documented in the National Pediatric Rheumatologic Database (NPRD) and the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) were used. Self-reported PA was collected from parents/guardians of children up to 11 years of age or adolescents 12 years of age and older. To compare PA-related data, age- and sex-specific pairwise analyses were conducted considering NPRD/KiGGS participants' data from 2017. Correlates of physical inactivity among patients were identified using a linear regression model. RESULTS: Data of 6,297 matched-pairs (mean age 11.2 ± 4.2 years, female 67%, patients' disease duration 4.5 ± 3.7 years, persistent oligoarthritis 43%) were available for evaluation. Almost 36% of patients aged 3-17 years (vs. 20% of controls) achieved the WHO recommended amount of PA, while PA steadily decreased with age (18% of patients aged ≥ 12 years) and varied between JIA categories. Female adolescents and patients with enthesitis-related arthritis were least likely to achieve the minimum recommended level of PA. Physical inactivity was associated with female sex, higher age at disease onset, longer disease duration, more functional disability (C-HAQ) and higher disease activity (cJADAS-10). CONCLUSIONS: Depending on JIA category, children and adolescents with JIA were similarly or even more likely to achieve the WHO recommended minimum level of PA compared to general population controls. However, since a large proportion of young JIA patients appear to be insufficiently physically active, engagement in targeted efforts to promote PA is urgently needed.

Canakinumab in the treatment of systemic juvenile idiopathic arthritis: a retrospective single center study in China.

Objective: Systemic juvenile idiopathic arthritis (sJIA) is characterized by excessive production of proinflammatory cytokines. As an anti-IL-1 agent, canakinumab has been approved in the USA and Europe for the treatment of sJIA patients aged ≥2 years. However, the use of canakinumab has never been reported in China. In this study, we aimed to assess the efficacy and safety of canakinumab in Chinese patients with sJIA. Methods: A total of 11 patients with sJIA who were treated with canakinumab were included in this study. Clinical data were collected retrospectively from medical records. Efficacy was evaluated by the systemic juvenile arthritis disease activity score (sJADAS). The follow-up was performed at canakinumab initiation, at months 1, 3, 6, 9 and 12, or at the last follow-up. Results: Of the 11 patients enrolled, 91.0% (10/11) had previously received treatment with tocilizumab. The mean duration of canakinumab was 9 (3-18) months. 45.5% (5/11) of patients showed complete response, 45.5% (5/11) showed partial response, and 9.0% (1/11) showed no response. 18.2% (2/11) experienced disease flare during the treatment with canakinumab. 81.8% (9/11) of patients successfully reduced the dose of corticosteroids, with six discontinuing corticosteroids. 45.6% (5/11) of patients experienced infection. No serious adverse events occurred during the treatment with canakinumab. Conclusions: Canakinumab may be effective and tolerable for Chinese sJIA patients, helping to reduce the dosage of corticosteroids. However, additional researches on large samples are required to evaluate its efficacy and safety.

Long-term efficacy and safety of subcutaneous tocilizumab in clinical trials of polyarticular or systemic juvenile idiopathic arthritis.

OBJECTIVE: To investigate the safety and efficacy of subcutaneous tocilizumab (SC-TCZ) treatment in a long-term extension (LTE) of clinical trials in polyarticular or systemic juvenile idiopathic arthritis (pJIA, sJIA). METHODS: Patients with pJIA or sJIA from two open-label, 52-week phase 1 b core trials of SC-TCZ who had adequate response per investigator assessment entered the LTE and continued SC-TCZ treatment according to body weight-based dosing regimens until commercial availability or up to 5 years. Pharmacokinetics, pharmacodynamics, and efficacy were assessed for up to 3 years and safety for up to 5 years in the LTE. RESULTS: Forty-four patients with pJIA and 38 patients with sJIA entered the LTE. Tocilizumab trough concentrations were maintained within the range expected to provide clinical benefit (mean values: pJIA, ∼10 µg/ml; sJIA, ∼75 µg/ml over 3 years). Pharmacodynamic parameters (interleukin-6, soluble interleukin-6 receptor, erythrocyte sedimentation rate, C-reactive protein) were maintained throughout the LTE at levels achieved in the core trials. Inactive disease per American College of Rheumatology provisional criteria was reported for 90% (17/19) and 53% (8/15) of patients with pJIA and 91% (10/11) and 92% (12/13) of patients with sJIA in the <30 kg and ≥30 kg body weight groups, respectively. Serious adverse events in the LTE were reported in six patients with pJIA (13.6%; five serious infections) and five patients with sJIA (13.2%; one serious infection). CONCLUSION: Patients with pJIA or sJIA experienced long-term disease control with SC-TCZ treatment. Long-term safety was consistent with the known tocilizumab safety profile.