Real-world application of the pediatric Glucocorticoid Toxicity Index in childhood-onset lupus.

OBJECTIVES: The pediatric Glucocorticoid Toxicity Index (pGTI) is a new, pediatric-specific tool to quantify glucocorticoid (GC)-related morbidity in children. We evaluated the feasibility and construct validity of retrospective pGTI scoring in patients with pediatric-onset systemic lupus erythematosus (pSLE) and identified risk factors for cumulative toxicity. METHODS: We conducted a retrospective cohort study of patients with pSLE treated with GCs at two pediatric centers (1999-2023). GC exposure was estimated using interval-averaged oral prednisone-equivalent dose and cumulative prednisone-equivalent dose. We scored change in GC toxicity every 6 months (±2) using a modified pGTI including 7 of 10 domains. We calculated the Cumulative Worsening Score (CWS), a continuous summation of toxicity accrued. Mixed effects linear regression was used to identify factors associated with CWS. RESULTS: There were 126 patients with pSLE, including 88 with nephritis, with a median of 6 visits/patient. Nearly half (47 %) experienced toxicity in the Blood Pressure domain. Other common toxicities were mood disturbance (25 %), followed by increased body mass index (BMI), striae, and sleep disturbance (21 % each). Decreased growth velocity was observed in 18 %. There was modest correlation between cumulative GC dose and CWS (rho 0.3; p < 0.01). Greater cumulative toxicity was associated with younger age, elevated BMI, and rituximab use at the time of GC initiation, albeit indications for the latter were not captured. CONCLUSIONS: Patients with pSLE experience a high burden of GC toxicity, particularly related to blood pressure, BMI, sleep, and growth. Standardized, pediatric-specific GC toxicity assessment is feasible in real-world settings and can facilitate evaluation of strategies to reduce morbidity in children requiring chronic GC treatment.

Transition to Adult Rheumatology Care: A Disease-Specific Guide.

ABSTRACT: Young adults with childhood-onset rheumatic diseases are more frequently establishing and continuing care with adult rheumatologists. The transfer of care can be challenging for both the young adult patients and their adult rheumatologists, in large part due to differences between pediatric-onset rheumatic diseases and their adult-onset counterparts, or due to the rarity of some pediatric-onset rheumatic conditions. Other challenges are due to cultural differences between pediatric and adult medical care and to the young adult needing to increasingly perform self-management skills that were previously managed by parents or other caregivers. In this review, we will provide a summary of strategies for working effectively with young adults as they transition to adult care. We will then discuss a subset of childhood-onset rheumatic diseases-including juvenile idiopathic arthritis, localized scleroderma, autoinflammatory diseases, pediatric-onset systemic lupus erythematosus, juvenile-onset dermatomyositis, and autoimmune encephalitis-for which clinical manifestations, management, and prognosis frequently differ between pediatric onset and adult onset. Our aim is to highlight differences that make caring for this population of transitioning young adults unique, providing tools and knowledge to empower the adult rheumatologist to care for these young adults in ways that are evidence-based, effective, efficient, and rewarding.

Racial and Ethnic Composition of Populations Served by Freestanding Children's Hospitals and Disparities in Outcomes of Pediatric Lupus.

OBJECTIVE: Health disparities may be driven by hospital-level factors. We assessed whether racial and ethnic composition of populations hospitals serve explain or modify disparities in hospital outcomes of children with systemic lupus erythematosus (SLE). METHODS: In this retrospective cohort study of patients 5 to 26 years old with SLE at 47 children's hospitals in the Pediatric Health Information System (2006-2021), race and ethnicity were assessed at the patient level and hospital level (proportion of total admissions composed of Black or Hispanic patients, respectively). Outcomes included intensive care unit (ICU) admission or adverse renal outcome (end-stage renal disease, dialysis, or transplant) during follow-up. We estimated racial and ethnic disparities, adjusted or stratified by hospital racial or ethnic composition. RESULTS: Of 8,125 patients with SLE, 2,293 (28%) required ICU admission, and 698 (9%) had an adverse renal outcome. Black and non-Hispanic White disparities in ICU admission were observed only at hospitals serving higher proportions of Black patients (odds ratio [OR] 1.29, 95% confidence interval [95% CI] 1.04-1.59 vs OR 1.07, 95% CI 0.83-1.38). Larger Black and non-Hispanic White disparities in adverse renal outcomes were observed at hospitals with higher Black racial composition (OR 2.0, 95% CI 1.4-2.8 vs OR 1.7, 95% CI 1.1-2.4). Conversely, Hispanic versus non-Hispanic disparities in renal outcomes persisted after adjustment for hospital-reported Hispanic ethnic composition but were observed only at hospitals with lower proportions of Hispanic patients. CONCLUSION: Worse Black and White disparities in SLE outcomes are observed at children's hospitals serving more Black children, whereas distinct patterns are observed for Hispanic and non-Hispanic disparities. Reporting of hospital characteristics related to populations served is needed to identify modifiable drivers of hospital-level variation.

Implications of Inflammatory Processes on a Developing Central Nervous System in Childhood-Onset Systemic Lupus Erythematosus.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that is increasingly affecting pediatric and adult populations. Neuropsychiatric manifestations (ie, cognitive dysfunction and mood disorders) appear to occur with greater severity and poorer prognosis in childhood-onset SLE (cSLE) versus adult-onset SLE, negatively impacting school function, self-management, and psychosocial health, as well as lifelong health-related quality of life. In this review, we describe pathogenic mechanisms active in cSLE, such as maladaptive inflammatory processes and ischemia, which are hypothesized to underpin central phenotypes in patients with cSLE, and the role of alterations in protective central nervous system (CNS) barriers (ie, the blood-brain barrier) are also discussed. Recent findings derived from novel neuroimaging approaches are highlighted because the methods employed in these studies hold potential for identifying CNS abnormalities that would otherwise remain undetected with conventional multiple resonance imaging studies (eg, T2-weighted or fluid-attenuated inversion recovery sequences). Furthermore, we propose that a more robust presentation of neuropsychiatric symptoms in cSLE is in part due to the harmful impact of a chronic inflammatory insult on a developing CNS. Although the immature status of the CNS may leave patients with cSLE more vulnerable to harboring neuropsychiatric manifestations, the same property may represent a greater urgency to reverse the maladaptive effects associated with a proneuroinflammatory state, provided that effective diagnostic tools and treatment strategies are available. Finally, considering the crosstalk among the CNS and other organ systems affected in cSLE, we postulate that a finer understanding of this interconnectivity and its role in the clinical presentation in cSLE is warranted.

Elevation of IL-17 Cytokines Distinguishes Kawasaki Disease From Other Pediatric Inflammatory Disorders.

OBJECTIVE: Kawasaki disease (KD) is a systemic vasculitis of young children that can lead to development of coronary artery aneurysms. We aimed to identify diagnostic markers to distinguish KD from other pediatric inflammatory diseases. METHODS: We used the proximity extension assay to profile proinflammatory mediators in plasma samples from healthy pediatric controls (n = 30), febrile controls (n = 26), and patients with KD (n = 23), multisystem inflammatory syndrome in children (MIS-C; n = 25), macrophage activation syndrome (n = 13), systemic and nonsystemic juvenile idiopathic arthritis (n = 14 and n = 10, respectively), and juvenile dermatomyositis (n = 9). We validated the key findings using serum samples from additional patients with KD (n = 37) and febrile controls (n = 28). RESULTS: High-fidelity proteomic profiling revealed distinct patterns of cytokine and chemokine expression across pediatric inflammatory diseases. Although KD and MIS-C exhibited many similarities, KD differed from MIS-C and other febrile diseases in that most patients exhibited elevation in one or more members of the interleukin-17 (IL-17) cytokine family, IL-17A, IL-17C, and IL-17F. IL-17A was particularly sensitive and specific, discriminating KD from febrile controls with an area under the receiver operator characteristic curve of 0.95 (95% confidence interval 0.89-1.00) in the derivation set and 0.91 (0.85-0.98) in the validation set. Elevation of all three IL-17-family cytokines was observed in over 50% of KD patients, including 19 of 20 with coronary artery aneurysms, but was rare in all other comparator groups. CONCLUSION: Elevation of IL-17 family cytokines is a hallmark of KD and may help distinguish KD from its clinical mimics.

Development of a Screening Algorithm for Lung Disease in Systemic Juvenile Idiopathic Arthritis.

OBJECTIVE: Lung disease (LD) is an increasingly recognized complication of systemic juvenile idiopathic arthritis (sJIA). As there are no currently available guidelines for pulmonary screening in sJIA, we sought to develop such an algorithm at our institution. METHODS: A multidisciplinary workgroup was convened, including members representing rheumatology, pulmonary, stem cell transplantation, and patient families. The workgroup leaders drafted an initial algorithm based on published literature and experience at our center. A modified Delphi approach was used to achieve agreement through three rounds of anonymous, asynchronous voting and a consensus meeting. Statements approved by the workgroup were rated as appropriate with moderate or high levels of consensus. These statements were organized into the final approved screening algorithm for LD in sJIA. RESULTS: The workgroup ultimately rated 20 statements as appropriate with a moderate or high level of consensus. The approved algorithm recommends pulmonary screening for newly diagnosed patients with sJIA with clinical features that the workgroup agreed may confer increased risk for LD. These "red flag features" include baseline characteristics (young age of sJIA onset, human leukocyte antigen type, trisomy 21), high disease activity (macrophage activation syndrome [MAS], sJIA-related ICU admission, elevated MAS biomarkers), respiratory symptoms or abnormal pulmonary examination findings, and features of drug hypersensitivity-like reactions (eosinophilia, atypical rash, anaphylaxis). The workgroup achieved consensus on the recommended pulmonary work-up and monitoring guidelines. CONCLUSION: We developed a pulmonary screening algorithm for sJIA-LD through a multidisciplinary consensus-building process, which will be revised as our understanding of sJIA-LD continues to evolve.

Type I interferon signature and cycling lymphocytes in macrophage activation syndrome.

BACKGROUNDMacrophage activation syndrome (MAS) is a life-threatening complication of Still's disease (SD) characterized by overt immune cell activation and cytokine storm. We aimed to further understand the immunologic landscape of SD and MAS.METHODWe profiled PBMCs from people in a healthy control group and patients with SD with or without MAS using bulk RNA-Seq and single-cell RNA-Seq (scRNA-Seq). We validated and expanded the findings by mass cytometry, flow cytometry, and in vitro studies.RESULTSBulk RNA-Seq of PBMCs from patients with SD-associated MAS revealed strong expression of genes associated with type I interferon (IFN-I) signaling and cell proliferation, in addition to the expected IFN-γ signal, compared with people in the healthy control group and patients with SD without MAS. scRNA-Seq analysis of more than 65,000 total PBMCs confirmed IFN-I and IFN-γ signatures and localized the cell proliferation signature to cycling CD38+HLA-DR+ cells within CD4+ T cell, CD8+ T cell, and NK cell populations. CD38+HLA-DR+ lymphocytes exhibited prominent IFN-γ production, glycolysis, and mTOR signaling. Cell-cell interaction modeling suggested a network linking CD38+HLA-DR+ lymphocytes with monocytes through IFN-γ signaling. Notably, the expansion of CD38+HLA-DR+ lymphocytes in MAS was greater than in other systemic inflammatory conditions in children. In vitro stimulation of PBMCs demonstrated that IFN-I and IL-15 - both elevated in MAS patients - synergistically augmented the generation of CD38+HLA-DR+ lymphocytes, while Janus kinase inhibition mitigated this response.CONCLUSIONMAS associated with SD is characterized by overproduction of IFN-I, which may act in synergy with IL-15 to generate CD38+HLA-DR+ cycling lymphocytes that produce IFN-γ.

Left atrial stiffness and strain are novel indices of left ventricular diastolic function in children: validation followed by application in multisystem inflammatory syndrome in children due to COVID-19.

AIMS: We hypothesized left atrial (LA) stiffness may serve as a surrogate marker in children to differentiate elevated pulmonary capillary wedge pressure (PCWP) from normal and help detect diastolic dysfunction in myocardial injury due to multisystem inflammatory syndrome in children (MIS-C). METHODS AND RESULTS: We validated LA stiffness in 76 patients (median age 10.5 years), 33 had normal PCWP (<12 mmHg) and 43 had elevated PCWP (≥12 mmHg). LA stiffness was applied to 42 MIS-C patients [28 with myocardial injury (+) and 14 without myocardial injury (-)], defined by serum biomarkers. The validation group consisted of a group with and without cardiomyopathies, whose PCWP values ranged from normal to severely elevated. Peak LA strain was measured by speckle-tracking and E/e' from apical four chamber views. Noninvasive LA stiffness was calculated as: LAStiffness=E/e'LAPeakStrain (%-1). Patients with elevated PCWP showed significantly elevated LA stiffness [median 0.71%-1 vs. 0.17%-1, P < 0.001]. Elevated PCWP group showed significantly decreased LA strain (median: 15.0% vs. 38.2%, P < 0.001). Receiver operator characteristic (ROC) curve for LA stiffness yielded an area under the curve (AUC) of 0.88 and cutoff value of 0.27%-1. In MIS-C group, ROC curve yielded an AUC of 0.79 and cutoff value of 0.29%-1 for identifying myocardial injury. CONCLUSION: In children with elevated PCWP, LA stiffness was significantly increased. When applied to children with MIS-C, LA stiffness classified myocardial injury accurately. LA stiffness and strain may serve as noninvasive markers of diastolic function in the pediatric population.

Opioid use in children with inflammatory bowel disease-related arthritis.

OBJECTIVES: Concomitant arthritis may increase risk of chronic opioid use in youngsters with IBD. We aimed to assess trends and clinical features associated with opioid use in children with IBD-related arthritis. METHODS: Adolescents under 18 years of age with IBD-related arthritis, at least 1 year of continuous enrolment, and at least 1 pharmacy claim in the Truven Health MarketScan Claims and Encounter Database were included. Subjects were identified using previously validated algorithms consisting of ICD codes, pharmacy claims and procedure codes. The primary outcome was chronic opioid exposure. Temporal trends in opioid exposure were tested using the Cuzick-Wilcoxon test. The association of chronic opioid use and baseline covariates in the IBD and IBD-arthritis cohorts were examined using multivariable logistic regression models. RESULTS: 14,943 adolescents with IBD, 480 of whom had arthritis, were included. Chronic opioid use was non-trivial in youngsters with IBD-related arthritis, higher than that of total IBD cohort (12.3% vs. 5%) and remained stable over the years of study. Using multivariable regression, joint pain and arthritis were significantly associated with chronic opioid exposure in young people with IBD. Among IBD-related arthritis patients older age, public insurance, gastrointestinal surgery, hospitalisation and psychiatric comorbidities were significantly associated with chronic opioid use. CONCLUSIONS: Chronic opioid use in adolescents with IBD-related arthritis was higher than that of total IBD cohort but stable over the years of study. Future study is needed to explore ways to optimise non-narcotic pain management strategies and ensuring appropriate use of opioids when necessary.

Improving Outcomes of Pediatric Lupus Care Delivery With Provider Goal-Setting Activities and Multidisciplinary Care Models.

OBJECTIVE: The present study was undertaken to evaluate high-quality care delivery in the context of provider goal-setting activities and a multidisciplinary care model using an electronic health record (EHR)-enabled pediatric lupus registry. We then determined associations between care quality and prednisone use among youth with systemic lupus erythematosus (SLE). METHODS: We implemented standardized EHR documentation tools to autopopulate a SLE registry. We compared pediatric Lupus Care Index (pLCI) performance (range 0.0-1.0; 1.0 representing perfect metric adherence) and timely follow-up 1) before versus during provider goal-setting activities and population management, and 2) in a multidisciplinary lupus nephritis versus rheumatology clinic. We estimated associations between pLCI and subsequent prednisone use adjusted for time, current medication, disease activity, clinical features, and social determinants of health. RESULTS: We analyzed 830 visits by 110 patients (median 7 visits per patient [interquartile range 4-10]) over 3.5 years. The provider-directed activity was associated with improved pLCI performance (adjusted ß 0.05 [95% confidence interval (95% CI) 0.01, 0.09]; mean 0.74 versus 0.69). Patients with nephritis in multidisciplinary clinic had higher pLCI scores (adjusted ß 0.06 [95% CI 0.02, 0.10]) and likelihood of timely follow-up than those in rheumatology (adjusted relative risk [RR] 1.27 [95% CI 1.02, 1.57]). A pLCI score of ≥0.50 was associated with 0.72-fold lower adjusted risk of subsequent prednisone use (95% CI 0.53, 0.93). Minoritized race, public insurance, and living in areas with greater social vulnerability were not associated with reduced care quality or follow-up, but public insurance was associated with higher risk of prednisone use. CONCLUSION: Greater attention to quality metrics is associated with better outcomes in childhood SLE. Multidisciplinary care models with population management may additionally facilitate equitable care delivery.

Variation in Early Anakinra Use and Short-Term Outcomes in Multisystem Inflammatory Syndrome in Children.

OBJECTIVE: Evidence regarding effectiveness of interleukin-1 receptor antagonism in multisystem inflammatory syndrome in children (MIS-C) is lacking. We characterized variation in initial treatment with anakinra and evaluated cardiovascular outcomes associated with adding anakinra to standard initial therapy. METHODS: We conducted a retrospective cohort study of MIS-C cases in a US surveillance registry from November 2020 to December 2021. Day 0 was the first calendar day of immunomodulatory treatment. Factors associated with initial anakinra use (days 0-1) were identified. We compared cases in patients ages 2-20 years receiving intravenous immunoglobulin (IVIG) and glucocorticoids versus anakinra plus IVIG and/or glucocorticoids on days 0-1, using inverse probability weighting to balance disease severity. Primary outcomes were vasopressor requirement on day 3 and impaired left ventricular ejection fraction on days 3-4. The secondary outcome was 50% reduction in C-reactive protein on day 3. RESULTS: Among 1,516 MIS-C cases at 44 sites, 193 (13%) patients received anakinra alone or with other immunomodulators as initial treatment (range 0-74% by site). Site accounted for 59% of residual variance in anakinra use. After balancing disease severity, initial treatment with anakinra plus IVIG and/or glucocorticoids (n = 121) versus IVIG plus glucocorticoids (n = 389) was not associated with significant differences in vasopressor requirement (25.6% versus 20.1%, respectively; risk ratio [RR] 1.27 [95% confidence interval (95% CI) 0.88-1.84]), ventricular dysfunction (33.7% versus 25.7%, respectively; RR 1.31 [95% CI 0.98-1.75]), or C-reactive protein reduction. CONCLUSION: We identified substantial variation in initial anakinra use in a real-world population of children with MIS-C, but no average short-term improvement in cardiovascular outcomes associated with early addition of anakinra to IVIG and/or glucocorticoids compared to IVIG and glucocorticoids alone.

Patient-Reported Outcomes Among Transition-Age Young Adults With Juvenile Idiopathic Arthritis in the Childhood Arthritis and Rheumatology Research Alliance Registry.

OBJECTIVE: To evaluate patient-reported care utilization and outcomes among young adults with juvenile idiopathic arthritis (JIA), including factors associated with complete transfer to adult rheumatology. METHODS: We included young adults with JIA enrolled in the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry from 2015 to 2019 with age ≥ 18 years at their last clinical site visit. We used data from the CARRA Registry Long-term Follow-up program, which follows inactive CARRA Registry patients and collects patient-reported information through phone surveys. We compared the characteristics of respondents with complete and incomplete transfer to adult rheumatology care at their first Long-term Follow-up phone survey. RESULTS: We identified 540 young adults with JIA; 187 (35%) responded to the Long-term Follow-up phone survey. The 54% of respondents with complete transfer to adult rheumatology were slightly older and reported more self-assessed disease activity, morning stiffness, and pain compared to those with incomplete transfer. Biologic use was high at both timepoints and did not differ by transfer status. Patients who completed the transfer were more likely to have private insurance and be actively pursuing postsecondary education compared to those with an incomplete transfer. Across the cohort, 65% reported problems with pain or discomfort and 45% with anxiety or depression. CONCLUSION: Young adult respondents with JIA in the CARRA Registry commonly report persistent medication use, but still report more problems with pain as compared to population norms. Additional work is needed to understand how best to address comorbid pain around the period of transition to adult care.

Implementation of Rheumatology Health Care Transition Processes and Adaptations to Systems Under Stress: A Mixed-Methods Study.

OBJECTIVES: Despite poor health care transition outcomes among young adults with pediatric rheumatic diseases, adoption of transition best practices is low. We sought to understand how structured transition processes were operationalized within pediatric rheumatology practices and what factors were perceived to enable adaptations during a global pandemic. METHODS: We conducted a mixed methods study of team leaders' experiences during an interim analysis of a pilot project to implement transition policy discussions at sites in the Childhood Arthritis and Rheumatology Research Alliance Transition Learning Collaborative. We combined quantitative assessments of organizational readiness for change (9 sites) and semistructured interviews of team leaders (8 sites) using determinants in the Exploration, Preparation, Implementation, Sustainment Framework. RESULTS: Engagement of nursing and institutional improvement efforts facilitated decisions to implement transition policies. Workflows incorporating educational processes by nonphysicians were perceived to be critical for success. When the pandemic disrupted contact with nonphysicians, capacity for automation using electronic medical record (EMR)-based tools was an important facilitator, but few sites could access these tools. Sites without EMR-based tools did not progress despite reporting high organizational readiness to implement change at the clinic level. Lastly, educational processes were often superseded by acute issues, such that youth with greater medical/psychosocial complexity may not receive the intervention. CONCLUSION: We generated several considerations to guide implementation of transition processes within pediatric rheumatology from the perspectives of team leaders. Careful assessment of institutional and nursing support is advisable before conducting complex transition interventions. Ideally, new strategies would ensure interventions reach youth with high complexity.

Pediatric to Adult Transition Literature: Scoping Review and Rheumatology Research Prioritization Survey Results.

The transition from pediatric to adult care is the focus of growing research. It is important to identify how to direct future research efforts for maximum effect. Our goals were to perform a scoping review of the transition literature, highlight gaps in transition research, and offer stakeholder guidance on the importance and feasibility of research questions designed to fill identified gaps. The transition literature on rheumatic diseases and other common pediatric-onset chronic diseases was grouped and summarized. Based on the findings, a survey was developed and disseminated to pediatric rheumatologists and young adults with rheumatic diseases as well as their caregivers. The transitional care needs of patients, healthcare teams, and caregivers is well described in the literature. While various transition readiness scales exist, no longitudinal posttransfer study confirms their predictive validity. Multiple outcome measures are used alone or in combination to define a successful transition or intervention. Multimodal interventions are most effective at improving transition-related outcomes. How broader health policy affects transition is poorly studied. Research questions that ranked highest for importance and feasibility included those related to identifying and tracking persons with psychosocial vulnerabilities or other risk factors for poor outcomes. Interventions surrounding improving self-efficacy and health literacy were also ranked highly. In contrast to healthcare teams (n = 107), young adults/caregivers (n = 23) prioritized research surrounding improved work, school, or social function. The relevant transition literature is summarized and future research questions prioritized, including the creation of processes to identify and support young adults vulnerable to poor outcomes.

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.

Hydroxychloroquine and immunosuppressant adherence patterns and their association with subsequent hospitalization rates among children with systemic lupus erythematosus.

OBJECTIVES: Using a representative sample of children with systemic lupus erythematosus (SLE) in the United States, we characterized prescription claim-based hydroxychloroquine and immunosuppressant adherence estimates and evaluated their concurrent and predictive validity. METHODS: We identified children ages 5-18 with SLE in the Truven Health MarketScan® Commercial and Medicaid claims databases (2013-2018). Among new users of hydroxychloroquine and immunosuppressant medications, we calculated proportion of days covered (PDC) over 365 days to estimate adherence by user group (mycophenolate, azathioprine, methotrexate, and any immunosuppressant use). Agreement between adherence estimates was evaluated with intraclass correlation coefficients (ICC) and kappa statistics. Separate negative binomial regression models were used to estimate associations between (a) hydroxychloroquine, (b) immunosuppressant, or (c) concurrent immunosuppressant/hydroxychloroquine non-adherence and subsequent hospitalizations, adjusted for baseline demographics, disease severity, and healthcare utilization. RESULTS: Among 423 new hydroxychloroquine/immunosuppressant users, 63% were Medicaid recipients. Sufficient adherence (PDC≥80%) ranged from 33 to 45% for immunosuppressants vs. 51-52% for hydroxychloroquine. Agreement between hydroxychloroquine and immunosuppressant adherence was modest overall, but better for mycophenolate (ICC 0.55) than methotrexate (0.27). Hydroxychloroquine non-adherence was associated with a 2.9-fold higher incidence of subsequent hospitalizations (95% CI [1.2-7.1]), whereas immunosuppressant and concurrent non-adherence were associated with 5.9 [2.4-14.6] and 5.6-fold [2.0-15.5] increased incidence, respectively. Use of concurrent adherence improved upon estimation of hospitalization risk compared to hydroxychloroquine adherence, but not immunosuppressant adherence alone. CONCLUSIONS: Hydroxychloroquine adherence is an imperfect proxy for adherence to other lupus medications among children with SLE, and therefore assessing immunosuppressant adherence concurrently adds value to hydroxychloroquine adherence assessments. Prescription claims-based immunosuppressant adherence measures are predictive of acute care utilization and may inform population management strategies.

Use of renin angiotensin aldosterone system inhibitors in children with lupus and time to glucocorticoid discontinuation.

There is little data to inform use of renin angiotensin aldosterone system (RAAS) inhibitors in pediatric patients with systemic lupus erythematosus (SLE). Here, we sought to characterize RAAS inhibitor use in pediatric SLE and determine whether early RAAS inhibitor initiation among children with incident lupus nephritis is associated with decreased duration of chronic glucocorticoid exposure. A retrospective cohort study was performed of children (ages 5-18) with SLE and/or lupus nephritis in the Truven MarketScan™ Medicaid and Commercial databases (2013-2018) and estimated RAAS inhibitor use. Among incident nephritis cases, we used competing risk hazard models with inverse probability of treatment weighting to estimate the association between RAAS inhibitor initiation less than 180 days after diagnosis and time to glucocorticoid discontinuation with kidney failure as a competing event. Among 592 children with nephritis and 1407 children with non-kidney SLE, 67% and 15% ever received RAAS inhibitors, respectively. Median duration of RAAS inhibitor use among 323 incident users was 14 and 9 months in children with and without nephritis, respectively. Medicaid enrollment was independently associated with greater likelihood of RAAS inhibitor use, irrespective of nephritis. Among 158 incident nephritis cases, early RAAS inhibitor initiation was significantly associated with a faster rate of glucocorticoid discontinuation (adjusted sub-distribution hazard ratio 1.81, 95% confidence interval [1.09 - 3.00]). Thus, early initiation of RAAS inhibitors may have a role in children newly diagnosed with lupus nephritis; not only those with refractory proteinuria after induction therapy. Hence, integrated health systems data could be leveraged to confirm these findings and optimize adjunctive therapies in pediatric lupus.

Racial Disparities in Renal Outcomes Over Time Among Hospitalized Children With Systemic Lupus Erythematosus.

OBJECTIVE: Racial and ethnic minority groups have excess morbidity related to renal disease in pediatric-onset systemic lupus erythematosus (SLE). This study was undertaken to evaluate temporal trends in renal outcomes and racial disparities among hospitalized children with SLE over a period of 14 years. METHODS: We identified patients 21 years old or younger with discharge diagnoses of SLE in the Pediatric Health Information System inpatient database (2006-2019). Adverse renal outcomes included end-stage renal disease (ESRD), dialysis, or transplant, analyzed as a composite and separately. We estimated the odds of adverse renal outcomes at any hospitalization or the first occurrence of an adverse renal outcome, adjusted for calendar period, patient characteristics, and clustering by hospital. We tested whether racial disparities differed by calendar period. RESULTS: There were 20,893 admissions for 7,434 SLE patients, of which 32%, 16%, 12%, and 8% were Black, Hispanic White, Hispanic Other, and Asian, respectively. Proportions of admissions with adverse renal outcomes decreased over time (P < 0.01). Black children remained at the highest risk of adverse renal outcomes at any admission (odds ratio [OR] 2.5 [95% confidence interval (95% CI) 1.8-3.5] versus non-Hispanic White patients). Black and Asian children remained at a higher risk of incident adverse renal outcomes, driven by ESRD among Black children (OR 1.6 [95% CI 1.2-2.1]) and dialysis among Asians (OR 1.7 [95% CI 1.1-2.7]). Relative disparities did not change significantly over time. CONCLUSION: Significant reductions in ESRD and dialysis occurred over time for children with SLE across all racial and ethnic groups. The lack of corresponding reductions in racial disparities highlights the need for targeted interventions to achieve greater treatment benefit among higher risk groups.

Clinical features, treatment patterns and short-term outcomes of children with inflammatory bowel disease evaluated in rheumatology clinic.

OBJECTIVES: This study evaluated the clinical features, treatment patterns, and short-term outcomes of children with inflammatory bowel disease (IBD)-associated musculoskeletal manifestations. METHODS: This was a retrospective cohort study of children with IBD evaluated for joint complaints in a paediatric rheumatology clinic from 2015 to 2020. The index visit was the date of initial rheumatology evaluation. Clinical features were evaluated using standard descriptive statistics. Differences in outcomes over time were compared using rank-sum tests. Univariate logistic regression was used to test associations between clinical features and persistent arthritis or enthesitis. RESULTS: Seventy-five patients met inclusion criteria. 61% had active arthritis or enthesitis at initial evaluation, 1/3 of whom were not yet diagnosed with IBD. Of those with known IBD, over half with joint complaints had arthritis or enthesitis. Active joint disease was common even among patients already receiving tumour necrosis factor (TNF) inhibitors or other immunomodulatory medications for IBD and despite inactive gastrointestinal disease. Treatment escalation was often needed to control articular disease, which included changes in immunomodulatory therapy and NSAIDs. Treatment outcomes for arthritis were good and significant improvements in functional mobility were observed (p<0.01), while enthesitis often persisted at follow-up (11/28, 39%). Moreover, a significant proportion of patients with pain at the index visit reported persistent pain at follow-up (29/44, 65%). CONCLUSIONS: This study provides several findings relevant to the multidisciplinary care of children with IBD, including high rates of active arthritis and enthesitis despite ongoing use of immunomodulatory medications for the management of IBD, responses to treatment, and pain management.