Identification of Plasma Metabolomic Biomarkers of Juvenile Idiopathic Arthritis.

Identification of disease and therapeutic biomarkers remains a significant challenge in the early diagnosis and effective treatment of juvenile idiopathic arthritis (JIA). In this study, plasma metabolomic profiling was conducted to identify disease-related metabolic biomarkers associated with JIA. Plasma samples from treatment-naïve JIA patients and non-JIA reference patients underwent global metabolomic profiling across discovery (60 JIA, 60 non-JIA) and replication (49 JIA, 38 non-JIA) cohorts.

Large-scale mutational analysis identifies UNC93B1 variants that drive TLR-mediated autoimmunity in mice and humans.

Nucleic acid-sensing Toll-like receptors (TLR) 3, 7/8, and 9 are key innate immune sensors whose activities must be tightly regulated to prevent systemic autoimmune or autoinflammatory disease or virus-associated immunopathology. Here, we report a systematic scanning-alanine mutagenesis screen of all cytosolic and luminal residues of the TLR chaperone protein UNC93B1, which identified both negative and positive regulatory regions affecting TLR3, TLR7, and TLR9 responses. We subsequently identified two families harboring heterozygous coding mutations in UNC93B1, UNC93B1+/T93I and UNC93B1+/R336C, both in key negative regulatory regions identified in our screen.

Capturing the Range of Disease Involvement in Localized Scleroderma: The Localized Scleroderma Total Severity Scale.

Objective: Juvenile localized scleroderma (jLS) is a chronic autoimmune disease commonly associated with poor outcomes, including contractures, hemiatrophy, uveitis, and seizures. Despite improvements in treatment, >25% of patients with jLS have functional impairment. To improve patient evaluation, our workgroup developed the Localized scleroderma Total Severity Scale (LoTSS), an overall disease severity measure.

Patient-Reported Outcomes Among Patients Ages Two to Seventeen Years With Polyarticular-Course Juvenile Idiopathic Arthritis Treated With Subcutaneous Abatacept: Two-Year Results From an International Phase III Study.

Objective: To describe longitudinal changes in patient-reported outcomes (PROs) in children with polyarticular-course juvenile idiopathic arthritis (pJIA) treated with subcutaneous abatacept.

Methods: Secondary analysis of a single-arm, open-label 24-month study of patients ages 6-17 years and 2-5 years. PROs included Childhood Health Assessment Questionnaire-Disability Index (CHAQ-DI), parent global assessment of child well-being (PaGA), pain assessment, and Activity Limitation Questionnaire (ALQ).

Mechanisms to expedite pediatric clinical trial site activation: The DOSE trial experience.

Background: Timely trial start-up is a key determinant of trial success; however, delays during start-up are common and costly. Moreover, data on start-up metrics in pediatric clinical trials are sparse. To expedite trial start-up, the Trial Innovation Network piloted three novel mechanisms in the trial titled Dexmedetomidine Opioid Sparing Effect in Mechanically Ventilated Children (DOSE), a multi-site, randomized, double-blind, placebo-controlled trial in the pediatric intensive care setting.

Conducting clinical trials in persons with Down syndrome: summary from the NIH INCLUDE Down syndrome clinical trials readiness working group.

The recent National Institute of Health (NIH) INCLUDE (INvestigation of Co-occurring conditions across the Lifespan to Understand Down syndromE) initiative has bolstered capacity for the current increase in clinical trials involving individuals with Down syndrome (DS). This new NIH funding mechanism offers new opportunities to expand and develop novel approaches in engaging and effectively enrolling a broader representation of clinical trials participants addressing current medical issues faced by individuals with DS. To address this opportunity, the NIH assembled leading clinicians, scientists, and representatives of advocacy groups to review existing methods and to identify those areas where new approaches are needed to engage and prepare DS populations for participation in clinical trial research.

2021 American College of Rheumatology Guideline for the Treatment of Juvenile Idiopathic Arthritis: Therapeutic Approaches for Oligoarthritis, Temporomandibular Joint Arthritis, and Systemic Juvenile Idiopathic Arthritis.

Objective: To provide updated guidelines for pharmacologic management of juvenile idiopathic arthritis (JIA), focusing on treatment of oligoarthritis, temporomandibular joint (TMJ) arthritis, and systemic JIA with and without macrophage activation syndrome. Recommendations regarding tapering and discontinuing treatment in inactive systemic JIA are also provided.

Methods: We developed clinically relevant Patient/Population, Intervention, Comparison, and Outcomes questions.

2021 American College of Rheumatology Guideline for the Treatment of Juvenile Idiopathic Arthritis: Recommendations for Nonpharmacologic Therapies, Medication Monitoring, Immunizations, and Imaging.

Objective: To provide recommendations for the management of juvenile idiopathic arthritis (JIA) with a focus on nonpharmacologic therapies, medication monitoring, immunizations, and imaging, irrespective of JIA phenotype.

Methods: We developed clinically relevant Patient/Population, Intervention, Comparison, and Outcomes questions. After conducting a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation approach was used to rate the quality of evidence (high, moderate, low, or very low).

2021 American College of Rheumatology Guideline for the Treatment of Juvenile Idiopathic Arthritis: Therapeutic Approaches for Oligoarthritis, Temporomandibular Joint Arthritis, and Systemic Juvenile Idiopathic Arthritis.

Objective: To provide updated guidelines for pharmacologic management of juvenile idiopathic arthritis (JIA), focusing on treatment of oligoarthritis, temporomandibular joint (TMJ) arthritis, and systemic JIA with and without macrophage activation syndrome. Recommendations regarding tapering and discontinuing treatment in inactive systemic JIA are also provided.

Methods: We developed clinically relevant Patient/Population, Intervention, Comparison, and Outcomes questions.

Metabolomic Profiling Identifies Exogenous and Microbiota-Derived Metabolites as Markers of Methotrexate Efficacy in Juvenile Idiopathic Arthritis.

Variability in methotrexate (MTX) efficacy represents a barrier to early and effective disease control in the treatment of juvenile idiopathic arthritis (JIA). This work seeks to understand the impact of MTX on the plasma metabolome and to identify metabolic biomarkers of MTX efficacy in a prospective cohort of children with JIA. Plasma samples from a cohort of children with JIA ( = 30) collected prior to the initiation of MTX and after 3 months of therapy were analyzed using a semi-targeted global metabolomic platform detecting 673 metabolites across a diversity of biochemical classes.

Low Etanercept Concentrations in Children With Obesity and Juvenile Idiopathic Arthritis.

Objective: To evaluate the impact of obesity on etanercept (ETN) drug exposure in children with juvenile idiopathic arthritis (JIA).

Methods: We conducted a pilot, cross-sectional, observational study in a real-world cohort of children with JIA receiving ETN as standard of care from a single center. We analyzed the relationship between body size and ETN plasma concentrations, adjusting for dosage.

Safety updates in novel therapeutics for pediatric rheumatic disease.

Purpose Of Review: Biologics and novel targeted therapeutics have transformed the management of pediatric rheumatic diseases over the past two decades; however, questions about short-term and long-term safety remain. Safety data gathered from recent clinical trials, long-term extensions of prior trials, registries, and other real-world evidence are summarized here for biologics and novel therapeutics commonly prescribed for pediatric rheumatic diseases.

Recent Findings: With nearly 20 years of therapeutic experience, tumor necrosis inhibitors (TNFi) are generally well tolerated, although infections, malignancy, and development of new autoimmunity remain a concern.

A population physiologically-based pharmacokinetic model to characterize antibody disposition in pediatrics and evaluation of the model using infliximab.

Aims: In order to better predict the pharmacokinetics (PK) of antibodies in children, and to facilitate dose optimization of antibodies in paediatric patients, there is a need to develop systems PK models that integrate ontogeny-related changes in human physiological parameters.

Methods: A population-based physiological-based PK (PBPK) model to characterize antibody PK in paediatrics has been developed, by incorporating age-related changes in body weight, organ weight, organ blood flow rate and interstitial volumes in a previously published platform model. The model was further used to perform Monte Carlo simulations to investigate clearance vs.

Factors associated with reduced infliximab exposure in the treatment of pediatric autoimmune disorders: a cross-sectional prospective convenience sampling study.

Background: Inadequate systemic exposure to infliximab (IFX) is associated with treatment failure. This work evaluated factors associated with reduced IFX exposure in children with autoimmune disorders requiring IFX therapy.

Methods: In this single-center cross-sectional prospective study IFX trough concentrations and anti-drug antibodies (ADAs) were measured in serum from children diagnosed with inflammatory bowel disease (IBD) (n = 73), juvenile idiopathic arthritis (JIA) (n = 16), or uveitis (n = 8) receiving maintenance IFX infusions at an outpatient infusion clinic in a tertiary academic pediatric hospital.

Use of Electronic Health Records to Identify Exposure-Response Relationships in Critically Ill Children: An Example of Midazolam and Delirium.

Adverse drug events are common in critically ill children and often result from systemic or target organ drug exposure. Methods of drug dosing and titration that consider pharmacokinetic alterations may improve our ability to optimally dose critically ill patients and reduce the risk for drug-related adverse events. To demonstrate this possibility, we explored the exposure-response relationship between midazolam and delirium in critically ill children.

Distinguishing Blau Syndrome from Systemic Sarcoidosis.

Purpose Of Review: The purpose of this review is to provide a framework to distinguish Blau syndrome/Early Onset Sarcoidosis and Sarcoidosis clinically. We also discuss relevant differences in genetics, pathogenesis, and management of these diseases.

Recent Findings: Blau syndrome and Sarcoidosis share the characteristic histologic finding of noncaseating granulomas as well as some similar clinical characteristics; nevertheless, they are distinct entities with important differences between them.

Down Syndrome-Associated Arthritis Cohort in the New Childhood Arthritis and Rheumatology Research Alliance Registry: Clinical Characteristics, Treatment, and Outcomes.

Objective: Down syndrome-associated arthritis (DA) is underrecognized, and current therapies used for juvenile idiopathic arthritis (JIA) appear to be poorly tolerated and less effective in patients with DA. The objective of this study was to characterize clinical manifestations and therapeutic preferences in DA compared to JIA, using the new Childhood Arthritis and Rheumatology Research Alliance (nCARRA) registry.

Methods: In a case-control study, between July 2015 and March 2019, patients with a diagnosis of JIA and Down syndrome (DS) were identified and matched by age, sex, and JIA subtype to patients who have JIA without DS.

Assessment and treatment of Down syndrome-associated arthritis: a survey of pediatric rheumatologists.

Background: Inflammatory arthritis in children with Down syndrome (DS) was first described in 1984 and is now termed Down syndrome-associated arthritis (DA). Studies have shown that DA is under-recognized with a 19-month average delay in diagnosis. Additionally, most patients present with polyarticular, rheumatoid factor (RF) and anti-nuclear antibody (ANA) negative disease.

Altered Folate Homeostasis in Children with Down Syndrome: A Potential Basis for Enhanced Methotrexate Toxicity.

Methotrexate is used to treat autoimmune and oncologic diseases in children with Down syndrome. However, increased methotrexate-related toxicity is reported in this population. We evaluated differences in the concentrations and distribution of erythrocyte folates in children with Down syndrome as a potential basis for this enhanced toxicity.

Association of *14 Allele with Poor Response to Methotrexate in Juvenile Idiopathic Arthritis Patients.

Objective: Variants in the gene, encoding a hepatic methotrexate (MTX) transporter, affect clearance of high-dose MTX. We tested whether in the *14 and *15 alleles of influenced the response to low-dose MTX in juvenile idiopathic arthritis (JIA) patients.

Methods: The study included 310 JIA patients genotyped for three single nucleotide polymorphisms (SNPs) in (rs4149056, rs2306283, and rs11045819).

Metabolomic Profiling to Identify Molecular Biomarkers of Cellular Response to Methotrexate In Vitro.

Variation in methotrexate (MTX) efficacy represents a significant barrier to early and effective disease control in the treatment of autoimmune arthritis. We hypothesize that the utilization of metabolomic techniques will allow for an improved understanding of the biochemical basis for the pharmacological activity of MTX, and can promote the identification and evaluation of novel molecular biomarkers of MTX response. In this work, erythroblastoid cells were exposed to MTX at the physiologic concentration of 1,000 nM and analyzed using three metabolomic platforms to give a broad spectrum of cellular metabolites.

Initial Results from a Pilot Comparative Effectiveness Study of 3 Methotrexate-based Consensus Treatment Plans for Juvenile Localized Scleroderma.

Objective: To perform a comparative effectiveness feasibility study in juvenile localized scleroderma (LS), using standardized treatment regimens (consensus treatment plans; CTP).

Methods: A prospective, multicenter 1-year pilot observational cohort study was performed by Childhood Arthritis and Rheumatology Research Alliance (CARRA) LS workgroup members. Patients with active, moderate to severe juvenile LS were treated with one of 3 CTP: methotrexate alone, or in combination with intravenous (30 mg/kg/dose for 3 mos) or oral corticosteroids (2 mg/kg/day tapered by 48 weeks).

Developing comparative effectiveness studies for a rare, understudied pediatric disease: lessons learned from the CARRA juvenile localized scleroderma consensus treatment plan pilot study.

Background: We designed and initiated a pilot comparative effectiveness study for juvenile localized scleroderma (jLS), for which there is limited evidence on best therapy. We evaluated the process we used, in relation to the specific protocol and to the general task of identifying strategies for implementing studies in rare pediatric diseases.

Methods: This was a prospective, multi-center, observational cohort study of 50 jLS patients initiating treatment, designed and conducted by the jLS group of the Childhood Arthritis and Rheumatology Research Alliance (CARRA) from 2012 to 2015.