The immunologic features of patients with early-onset and polyautoimmunity.

Inflammatory conditions are increasingly described in patients with primary immunodeficiencies; however, little is known about the prevalence of immune defects in patients who present first with autoimmunity. We describe the immunologic features of children with early-onset/polyautoimmunity followed in the Multiple Autoimmunity and Immunodeficiency (MAID) Clinic, where patients are co-managed by rheumatologists and immunologists. The most common autoimmune manifestations were cytopenias, lymphoproliferation, and colitis. Recurrent infections were noted in 65% of patients. Abnormalities in lymphocyte subsets and immunoglobulins were common. A pathogenic variant was identified in 19% of patients, and 2 novel inherited disorders were discovered. Additionally, 42% of patients had treatment changes implemented in the MAID clinic. By evaluating this unique cohort of patients, we report on the immunologic underpinning of early-onset/polyautoimmunity. The high rate of genetic diagnoses and treatment interventions in this population highlights the value of collaboration between rheumatologists and immunologists in the care of these complex patients.

Emergent high fatality lung disease in systemic juvenile arthritis.

OBJECTIVE: To investigate the characteristics and risk factors of a novel parenchymal lung disease (LD), increasingly detected in systemic juvenile idiopathic arthritis (sJIA). METHODS: In a multicentre retrospective study, 61 cases were investigated using physician-reported clinical information and centralised analyses of radiological, pathological and genetic data. RESULTS: LD was associated with distinctive features, including acute erythematous clubbing and a high frequency of anaphylactic reactions to the interleukin (IL)-6 inhibitor, tocilizumab. Serum ferritin elevation and/or significant lymphopaenia preceded LD detection. The most prevalent chest CT pattern was septal thickening, involving the periphery of multiple lobes ± ground-glass opacities. The predominant pathology (23 of 36) was pulmonary alveolar proteinosis and/or endogenous lipoid pneumonia (PAP/ELP), with atypical features including regional involvement and concomitant vascular changes. Apparent severe delayed drug hypersensitivity occurred in some cases. The 5-year survival was 42%. Whole exome sequencing (20 of 61) did not identify a novel monogenic defect or likely causal PAP-related or macrophage activation syndrome (MAS)-related mutations. Trisomy 21 and young sJIA onset increased LD risk. Exposure to IL-1 and IL-6 inhibitors (46 of 61) was associated with multiple LD features. By several indicators, severity of sJIA was comparable in drug-exposed subjects and published sJIA cohorts. MAS at sJIA onset was increased in the drug-exposed, but was not associated with LD features. CONCLUSIONS: A rare, life-threatening lung disease in sJIA is defined by a constellation of unusual clinical characteristics. The pathology, a PAP/ELP variant, suggests macrophage dysfunction. Inhibitor exposure may promote LD, independent of sJIA severity, in a small subset of treated patients. Treatment/prevention strategies are needed.

Multiple juvenile idiopathic arthritis subtypes demonstrate proinflammatory IgG glycosylation.

OBJECTIVE: Rheumatoid arthritis is associated with an excess of agalactosylated (G0) IgG that is considered relatively proinflammatory. Assessment of this association in juvenile idiopathic arthritis (JIA) is complicated by age-dependent IgG glycan variation. The aim of this study was to conduct the first large-scale survey of IgG glycans in healthy children and patients with JIA, with a focus on early childhood, the time of peak JIA incidence. METHODS: IgG glycans from healthy children and disease-modifying antirheumatic drug-naive patients with JIA were characterized using high-performance liquid chromatography. Agalactosylated glycans were quantitated with reference to monogalactosylated (G1) species. Associations were sought between the G0:G1 ratio and disease characteristics. RESULTS: Among healthy children ages 9 months to 16 years (n = 165), the G0:G1 ratio was highly age dependent, with the ratio peaking to 1.19 in children younger than age 3 years and declining to a nadir of 0.83 after age 10 years (Spearman's ρ = 0.60, P < 0.0001). In patients with JIA (n = 141), the G0:G1 ratio was elevated compared with that in control subjects (1.32 versus 1.02; P < 0.0001). The G0:G1 ratio corrected for age was abnormally high in all JIA subtypes (enthesitis-related arthritis was not assessed), most strikingly in systemic JIA. Glycosylation aberrancy was comparable in patients with and those without antinuclear antibodies and in both early- and late-onset disease and exhibited at most a weak correlation with markers of inflammation. CONCLUSION: IgG glycosylation is skewed toward proinflammatory G0 variants in healthy children, in particular during the first few years of life. This deviation is exaggerated in patients with JIA. The role for IgG glycan variation in immune function in children, including the predilection of JIA for early childhood, remains to be defined.

A taste of periodic fever syndromes.

Periodic fevers are acquired or inherited disorders of innate immunity, which were first described in the 1940s. The patients are typically young at onset and have regularly recurring fevers for a few days to a few weeks with systemic inflammatory symptoms that are interrupted by symptom-free periods. There is a variety of clinical manifestations including gastrointestinal complaints, myalgias, arthralgias, and rash. A differential diagnosis in these patients may include recurrent infections, other inflammatory disorders, and neoplastic disease. This clinical review focuses on a sample of autoinflammatory disorders including familial Mediterranean fever, tumor necrosis factor receptor 1-associated periodic syndrome, hyperimmunoglobulinemia D syndrome, the cryopyrin-associated periodic syndrome, and periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis syndrome. We review the basics, pertinent clinical and laboratory features, and management of each entity.

Pediatric Rheumatology Care and Outcomes Improvement Network's Quality Measure Set to Improve Care of Children With Juvenile Idiopathic Arthritis.

OBJECTIVE: To describe the selection, development, and implementation of quality measures (QMs) for juvenile idiopathic arthritis (JIA) by the Pediatric Rheumatology Care and Outcomes Improvement Network (PR-COIN), a multihospital learning health network using quality improvement methods and leveraging QMs to drive improved outcomes across a JIA population since 2011. METHODS: An American College of Rheumatology-endorsed multistakeholder process previously selected initial process QMs. Clinicians in PR-COIN and parents of children with JIA collaboratively selected outcome QMs. A committee of rheumatologists and data analysts developed operational definitions. QMs were programmed and validated using patient data. Measures are populated by registry data, and performance is displayed on automated statistical process control charts. PR-COIN centers use rapid-cycle quality improvement approaches to improve performance metrics. The QMs are revised for usefulness, to reflect best practices, and to support network initiatives. RESULTS: The initial QM set included 13 process measures concerning standardized measurement of disease activity, collection of patient-reported outcome assessments, and clinical performance measures. Initial outcome measures were clinical inactive disease, low pain score, and optimal physical functioning. The revised QM set has 20 measures and includes additional measures of disease activity, data quality, and a balancing measure. CONCLUSION: PR-COIN has developed and tested JIA QMs to assess clinical performance and patient outcomes. The implementation of robust QMs is important to improve quality of care. PR-COIN's set of JIA QMs is the first comprehensive set of QMs used at the point-of-care for a large cohort of JIA patients in a variety of pediatric rheumatology practice settings.

Incidence and Risk Factors for Eosinophilia and Lung Disease in Biologic-Exposed Children With Systemic Juvenile Idiopathic Arthritis.

OBJECTIVE: Although interleukin-1 (IL-1)/IL-6 inhibitors are effective therapies for systemic juvenile idiopathic arthritis (JIA), some patients develop eosinophilia and lung disease during treatment. This study was undertaken to retrospectively evaluate incidence and risk factors for eosinophilia and describe lung disease outcomes in IL-1/IL-6 inhibitor-exposed patients with systemic JIA. METHODS: Among JIA patients at our institution exposed to interleukin-1 (IL-1)/IL-6 inhibitors (1995-2022), we compared incidence rate of eosinophilia in systemic JIA compared to other JIA, stratified by medication class (IL-1/IL-6 inhibitors, other cytokine inhibitors, methotrexate). We used Cox models to identify predictors of eosinophilia during IL-1/IL-6 inhibitor use and summarized treatment changes and outcomes after eosinophilia, including lung disease. HLA typing was performed on a clinical or research basis. RESULTS: There were 264 new medication exposures in 75 patients with systemic JIA and 41 patients with other JIA. A total of 49% of patients with systemic JIA with HLA typing (n = 45) were positive for HLA-DRB1*15 alleles. Eosinophilia was common during IL-1/IL-6 inhibitor use and did not differ by systemic JIA compared to other JIA (0.08 and 0.07 per person-year, respectively; P = 0.30). Among systemic JIA patients, pretreatment macrophage activation syndrome (MAS) was associated with a higher rate of subsequent eosinophilia on biologic therapy (unadjusted hazard ratio 3.2 [95% confidence interval 1.2-8.3]). A total of 4 of 5 patients who switched therapy within 10 weeks of eosinophilia experienced disease flare compared to none of the patients who continued the original therapy. A total of 8 of 25 patients with pulmonary evaluations had lung disease, and all had severe manifestations of systemic JIA (MAS, intensive care unit stay). One death was attributed to systemic JIA-lung disease. CONCLUSION: Eosinophilia is common in JIA patients using IL-1/IL-6 inhibitors. Severe disease may be associated with eosinophilia and lung disease in systemic JIA.

Regulation of human neutrophil Fcγ receptor IIa by C5a receptor promotes inflammatory arthritis in mice.

OBJECTIVE: Rheumatoid arthritis culminates in joint destruction that, in mouse models of disease, is supported by innate immune molecules, including Fcγ receptors (FcγR) and complement. However, these findings may not be predictive of the outcome in humans, given the structural differences between murine and human activating FcγR on neutrophils, a prominent component of joint exudates. The aim of this study was to examine the role of human neutrophil FcγRIIa in the development of arthritis and probe the underlying mechanism by which FcγRIIa initiates disease. METHODS: K/BxN mouse serum transfer-induced arthritis was examined in mice expressing human FcγRIIa on neutrophils but lacking their own activating FcγR (γ-chain-deficient mice). The role of mast cells, complement (C3 and C5a), and CD18 integrins in FcγRIIa-initiated disease was examined using cell reconstitution approaches, inhibitors, and functional blocking antibodies, respectively. Crosstalk between the complement receptor C5aR and FcγRIIa on neutrophils was evaluated in vitro. RESULTS: The expression of human FcγRIIa on neutrophils was sufficient to restore susceptibility to K/BxN serum-induced neutrophil recruitment, synovitis, and bone destruction in γ-chain-deficient mice. Joint inflammation was robust and proceeded even in the absence of mast cells and vascular permeability, features shown to contribute to disease in wild-type mice. Neutrophil recruitment was dependent on the presence of a CD18 integrin, lymphocyte function-associated antigen 1, and C5aR. In addition, C5aR significantly enhanced FcγRIIa-mediated phagocytosis and oxidative burst in vitro. CONCLUSION: Human and murine activating FcγR on neutrophils are not functionally equivalent, and in humans, they may play a primary role in arthritis. Crosstalk between neutrophil C5aR and FcγRIIa is essential for disease progression, thus highlighting a new aspect of complement during the effector phase of inflammatory arthritis.

Longitudinal assessment of preparation for care transition among adolescents and young adults with rheumatologic disease: a single-center pilot study.

Adolescents and young adults (AYA) with rheumatologic diseases are at high risk for poor outcomes and gaps in care when transitioning from pediatric to adult care. However, tools for evaluating transition readiness and assessing the impact of transition interventions are limited. We implemented a written transition policy at our pediatric rheumatology center and evaluated preparation for transition among AYA 16 and older before and after distribution. 31 of 77 patients completed the follow-up survey (response rate 40%). Patient report of transition counseling increased following written transition policy implementation, though these results were not statistically significant in our small cohort. Most follow-up respondents (n = 19, 61%) had not yet completed care transfer; 4 (13%) had arranged a visit with an adult rheumatologist and 8 (26%) had fully transitioned to adult care. Those who successfully completed care transfer were older, had completed higher levels of education, and had significantly higher baseline transition preparation scores compared to those with no transfer arranged or planned visit only. Our single-center pilot study demonstrated that longitudinal assessment of transition preparation is feasible and that scores are significantly associated with care transfer outcomes. Tracking transition preparation over time may provide practices with information on areas of highest need for transition guidance and predict successful transfer among AYA with rheumatologic disease.

Consensus Approach to a Treat-to-target Strategy in Juvenile Idiopathic Arthritis Care: Report From the 2020 PR-COIN Consensus Conference.

OBJECTIVE: Treat to target (T2T) is a strategy of adjusting treatment until a target is reached. An international task force recommended T2T for juvenile idiopathic arthritis (JIA) treatment. Implementing T2T in a standard and reliable way in clinical practice requires agreement on critical elements of (1) target setting, (2) T2T strategy, (3) identifying barriers to implementation, and (4) patient eligibility. A consensus conference was held among Pediatric Rheumatology Care and Outcomes Improvement Network (PR-COIN) stakeholders to inform a statement of understanding regarding the PR-COIN approach to T2T. METHODS: PR-COIN stakeholders including 16 healthcare providers and 4 parents were invited to form a voting panel. Using the nominal group technique, 2 rounds of voting were held to address the above 4 areas to select the top 10 responses by rank order. RESULTS: Incorporation of patient goals ranked most important when setting a treatment target. Shared decision making (SDM), tracking measurable outcomes, and adjusting treatment to achieve goals were voted as the top elements of a T2T strategy. Workflow considerations, and provider buy-in were identified as key barriers to T2T implementation. Patients with JIA who had poor prognostic factors and were at risk for high disease burden were leading candidates for a T2T approach. CONCLUSION: This consensus conference identified the importance of incorporating patient goals as part of target setting and of the influence of patient stakeholder involvement in drafting treatment recommendations. The network approach to T2T will be modified to address the above findings, including solicitation of patient goals, optimizing SDM, and better workflow integration.

Proteomics based markers of clinical pain severity in juvenile idiopathic arthritis.

INTRODUCTION: Juvenile idiopathic arthritis (JIA) is a cluster of autoimmune rheumatic diseases occurring in children 16 years of age or less. While it is well-known that pain may be experienced during inflammatory and non-inflammatory states, much remains ambiguous regarding the molecular mechanisms that may drive JIA pain. Thus, in this pilot study, we explored the variability of the serum proteomes in relation to pain severity in a cohort of JIA patients. METHODS: Serum samples from 15 JIA patients (male and female, 12.7 ± 2.8 years of age) were assessed using liquid chromatography/mass spectrometry (LC/MS). Correlation analyses were performed to determine the relationships among protein levels and self-reported clinical pain severity. Additionally, how the expression of pain-associated proteins related to markers of inflammation (Erythrocyte Sedimentation Rate (ESR)) or morphological properties of the central nervous system (subcortical volume and cortical thickness) implicated in JIA were also evaluated. RESULTS: 306 proteins were identified in the JIA cohort of which 14 were significantly (p < 0.05) associated with clinical pain severity. Functional properties of the identified pain-associated proteins included but were not limited to humoral immunity (IGLV3.9), inflammatory response (PRG4) and angiogenesis (ANG). Associations among pain-associated proteins and ESR (IGHV3.9, PRG4, CST3, VWF, ALB), as well as caudate nucleus volume (BTD, AGT, IGHV3.74) and insular cortex thickness (BTD, LGALS3BP) were also observed. CONCLUSIONS: The current proteomic findings suggest both inflammatory- and non-inflammatory mediated mechanisms as potential factors associated with JIA pain. Validation of these preliminary observations using larger patient cohorts and a longitudinal study design may further point to novel serologic markers of pain in JIA.

An Evidence-Based Guideline Improves Outcomes for Patients With Hemophagocytic Lymphohistiocytosis and Macrophage Activation Syndrome.

OBJECTIVE: To compare clinical outcomes in children with hemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS) who were managed before and after implementation of an evidence-based guideline (EBG). METHODS: A management algorithm for MAS-HLH was developed at our institution based on literature review, expert opinion, and consensus building across multiple pediatric subspecialties. An electronic medical record search retrospectively identified hospitalized patients with MAS-HLH in the pre-EBG (October 15, 2015, to December 4, 2017) and post-EBG (January 1, 2018, to January 21, 2020) time periods. Predetermined outcome metrics were evaluated in the 2 cohorts. RESULTS: After the EBG launch, 57 children were identified by house staff as potential patients with MAS-HLH, and rheumatology was consulted for management. Ultimately, 17 patients were diagnosed with MAS-HLH by the treating team. Of these, 59% met HLH 2004 criteria, and 94% met 2016 classification criteria for MAS complicating systemic juvenile idiopathic arthritis. There was a statistically significant reduction in mortality from 50% before implementation of the EBG to 6% in the post-EBG cohort (P = 0.02). There was a significant improvement in time to 50% reduction in C-reactive protein level in the post-EBG vs pre-EBG cohorts (log-rank P < 0.01). There were trends toward faster time to MAS-HLH diagnosis, faster initiation of immunosuppressive therapy, shorter length of hospital stay, and more rapid normalization of MAS-HLH-related biomarkers in the patients post-EBG. CONCLUSION: While the observed improvements may be partially attributed to advances in treatment of MAS-HLH that have accumulated over time, this analysis also suggests that a multidisciplinary treatment pathway for MAS-HLH contributed meaningfully to favorable patient outcomes.

Disordered T cell-B cell interactions in autoantibody-positive inflammatory arthritis.

T peripheral helper (Tph) cells, identified in the synovium of adults with seropositive rheumatoid arthritis, drive B cell maturation and antibody production in non-lymphoid tissues. We sought to determine if similarly dysregulated T cell-B cell interactions underlie another form of inflammatory arthritis, juvenile oligoarthritis (oligo JIA). Clonally expanded Tph cells able to promote B cell antibody production preferentially accumulated in the synovial fluid (SF) of oligo JIA patients with antinuclear antibodies (ANA) compared to autoantibody-negative patients. Single-cell transcriptomics enabled further definition of the Tph gene signature in inflamed tissues and showed that Tph cells from ANA-positive patients upregulated genes associated with B cell help to a greater extent than patients without autoantibodies. T cells that co-expressed regulatory T and B cell-help factors were identified. The phenotype of these Tph-like Treg cells suggests an ability to restrain T cell-B cell interactions in tissues. Our findings support the central role of disordered T cell-help to B cells in autoantibody-positive arthritides.

Aberrant IgG galactosylation precedes disease onset, correlates with disease activity, and is prevalent in autoantibodies in rheumatoid arthritis.

OBJECTIVE: To examine the association between aberrant IgG galactosylation and disease parameters in rheumatoid arthritis (RA). METHODS: Analysis of N-glycan in serum samples from multiple cohorts was performed. The IgG N-glycan content and the timing of N-glycan aberrancy relative to disease onset were compared in healthy subjects and in patients with RA. Correlations between aberrant galactosylation and disease activity were assessed in the RA cohorts. The impact of disease activity, sex, age, anti-cyclic citrullinated peptide (anti-CCP) antibody titer, disease duration, and C-reactive protein level on aberrant galactosylation was determined using multivariate analysis. The N-glycan content was also compared between epitope affinity-purified autoantibodies and the remaining IgG repertoire in RA patients. RESULTS: Our results confirm the aberrant galactosylation of IgG in RA patients as compared with healthy controls (mean +/- SD 1.36 +/- 0.43 versus 1.01 +/- 0.23; P < 0.0001). We observed a significant correlation between levels of aberrant IgG galactosylation and disease activity (Spearman's rho = 0.37, P < 0.0001). This correlation was higher in women (Spearman's rho = 0.60, P < 0.0001) than in men (Spearman's rho = 0.16, P = 0.10). Further, aberrant IgG galactosylation substantially predated the onset of arthritis and the diagnosis of RA (3.5 years) and resided selectively in the anticitrullinated antigen fraction. CONCLUSION: Our findings identify aberrant IgG galactosylation as a dysregulated component of the humoral immune response in RA that begins prior to disease onset, associates with disease activity in a sex-specific manner, and resides preferentially in autoantibodies.

Vestibular Evaluation and Management of Children with Sensorineural Hearing Loss.

Vestibular dysfunction is the most common comorbidity associated with childhood sensorineural hearing loss. Early identification of vestibular dysfunction enables early intervention to mitigate its impact of motor, behavioral, and neurocognitive deficits of developing children. Screening for vestibular impairment can be achieved in the busy clinical setting.

A multidisciplinary assessment of pain in juvenile idiopathic arthritis.

INTRODUCTION: Pain is prevalent in juvenile idiopathic arthritis (JIA). Unknowns regarding the biological drivers of pain complicate therapeutic targeting. We employed neuroimaging to define pain-related neurobiological features altered in JIA. METHODS: 16 male and female JIA patients (12.7 ± 2.8 years of age) on active treatment were enrolled, together with age- and sex-matched controls. Patients were assessed using physical examination, clinical questionnaires, musculoskeletal MRI, and structural neuroimaging. In addition, functional magnetic resonance imaging (fMRI) data were collected during the resting-state, hand-motor task performance, and cold stimulation of the hand and knee. RESULTS: Patients with and without pain and with and without inflammation (joint and systemic) were evaluated.  Pain severity was associated with more physical stress and poorer cognitive function. Corrected for multiple comparisons, morphological analysis revealed decreased cortical thickness within the insula cortex and a negative correlation between caudate nucleus volume and pain severity. Functional neuroimaging findings suggested alteration within neurocircuitry structures regulating emotional pain processing (anterior insula) in addition to the default-mode and sensorimotor networks. CONCLUSIONS: Patients with JIA may exhibit changes in neurobiological circuits related to pain. These preliminary findings suggest mechanisms by which pain could potentially become dissociated from detectable joint pathology and persist independently of inflammation or treatment status.

Th1 polarization defines the synovial fluid T cell compartment in oligoarticular juvenile idiopathic arthritis.

Oligoarticular juvenile idiopathic arthritis (oligo JIA) is the most common form of chronic inflammatory arthritis in children, yet the cause of this disease remains unknown. To understand immune responses in oligo JIA, we immunophenotyped synovial fluid T cells with flow cytometry, bulk RNA-Seq, single-cell RNA-Seq (scRNA-Seq), DNA methylation studies, and Treg suppression assays. In synovial fluid, CD4+, CD8+, and γδ T cells expressed Th1-related markers, whereas Th17 cells were not enriched. Th1 skewing was prominent in CD4+ T cells, including Tregs, and was associated with severe disease. Transcriptomic studies confirmed a Th1 signature in CD4+ T cells from synovial fluid. The regulatory gene expression signature was preserved in Tregs, even those exhibiting Th1 polarization. These Th1-like Tregs maintained Treg-specific methylation patterns and suppressive function, supporting the stability of this Treg population in the joint. Although synovial fluid CD4+ T cells displayed an overall Th1 phenotype, scRNA-Seq uncovered heterogeneous effector and regulatory subpopulations, including IFN-induced Tregs, peripheral helper T cells, and cytotoxic CD4+ T cells. In conclusion, oligo JIA is characterized by Th1 polarization that encompasses Tregs but does not compromise their regulatory identity. Targeting Th1-driven inflammation and augmenting Treg function may represent important therapeutic approaches in oligo JIA.

Providing Inpatient Medical Care to Children With Autism Spectrum Disorder.

Autism spectrum disorder (ASD) is a common neurodevelopmental disorder, affecting an estimated 1 in 40 children. Children with ASD have high rates of medical comorbidity and often experience high levels of distress during medical admissions, increasing the risk of agitation. Pediatric hospitalists receive minimal formal training on the inpatient care of children with ASD. In this article, we review strategies that pediatric hospitalists can use to optimize the care of children with ASD during inpatient admissions. These include gathering an ASD-related history early in the admission to understand the child's baseline core ASD symptoms, including social and communication ability, sensory needs, and restricted or repetitive behaviors. This information can be used to tailor the hospitalist's approach in each of these 3 domains. We conclude by reviewing procedure-related considerations, an approach to managing agitation, and quality improvement interventions.

On the Alert for Cytokine Storm: Immunopathology in COVID-19.

Poor outcomes in COVID-19 correlate with clinical and laboratory features of cytokine storm syndrome. Broad screening for cytokine storm and early, targeted antiinflammatory therapy may prevent immunopathology and could help conserve limited health care resources. While studies are ongoing, extrapolating from clinical experience in cytokine storm syndromes may benefit the multidisciplinary teams caring for patients with severe COVID-19.