EULAR/PRES recommendations for vaccination of paediatric patients with autoimmune inflammatory rheumatic diseases: update 2021.

OBJECTIVES: Recent insights supporting the safety of live-attenuated vaccines and novel studies on the immunogenicity of vaccinations in the era of biological disease-modifying antirheumatic drugs in paediatric patients with autoimmune/inflammatory rheumatic diseases (pedAIIRD) necessitated updating the EULAR recommendations. METHODS: Recommendations were developed using the EULAR standard operating procedures. Two international expert committees were formed to update the vaccination recommendations for both paediatric and adult patients with AIIRD. After a systematic literature review, separate recommendations were formulated for paediatric and adult patients. For pedAIIRD, six overarching principles and seven recommendations were formulated and provided with the level of evidence, strength of recommendation and Task Force level of agreement. RESULTS: In general, the National Immunisation Programmes (NIP) should be followed and assessed yearly by the treating specialist. If possible, vaccinations should be administered prior to immunosuppressive drugs, but necessary treatment should never be postponed. Non-live vaccines can be safely given to immunosuppressed pedAIIRD patients. Mainly, seroprotection is preserved in patients receiving vaccinations on immunosuppression, except for high-dose glucocorticoids and B-cell depleting therapies. Live-attenuated vaccines should be avoided in immunosuppressed patients. However, it is safe to administer the measles-mumps-rubella booster and varicella zoster virus vaccine to immunosuppressed patients under specific conditions. In addition to the NIP, the non-live seasonal influenza vaccination should be strongly considered for immunosuppressed pedAIIRD patients. CONCLUSIONS: These recommendations are intended for paediatricians, paediatric rheumatologists, national immunisation agencies, general practitioners, patients and national rheumatology societies to attain safe and effective vaccination and optimal infection prevention in immunocompromised pedAIIRD patients.

Siglec-1 expression on monocytes is associated with the interferon signature in juvenile dermatomyositis and can predict treatment response.

OBJECTIVE: JDM is a rare chronic immune-mediated inflammatory disease with a predominant role for type I IFN responses. We aimed to determine the potential of Siglec-1 expression on monocytes as a novel IFN-inducible biomarker for disease activity monitoring and prediction of treatment response in patients with JDM. METHODS: Siglec-1 was measured by flow cytometry on circulating monocytes of 21 newly diagnosed JDM patients before start of treatment and, for 10 of these, also during follow-up. The expression levels of five type I IFN-stimulated genes, MX1, IFI44, IFI44L, LY6E and IFIT3, were measured by RT-qPCR to determine the IFN signature and calculate an IFN score. IFN-inducible plasma proteins CXCL10 and galectin-9 were measured by multiplex immunoassay. RESULTS: Siglec-1 and IFN score were increased in JDM patients compared with controls and correlated with clinical disease activity. Stratification of patients by Siglec-1 expression at diagnosis identified those with high Siglec-1 expression as having a higher risk of requiring treatment intensification within the first 3 months after diagnosis (55% vs 0% of patients, P = 0.01). Siglec-1 expression strongly correlated with plasma levels of previously validated biomarkers CXCL10 (rs = 0.81, P < 0.0001) and galectin-9 (rs = 0.83, P < 0.0001), and was superior to the IFN score in predicting treatment response (area under the curve 0.87 vs 0.53, P = 0.01). CONCLUSION: Siglec-1 on monocytes is a novel IFN-inducible biomarker in JDM that correlates with clinical disease activity and identifies patients at risk for a suboptimal treatment response. Further studies are required to validate these findings and their clinical potential.

A phase I/II study of bevacizumab, irinotecan and erlotinib in children with progressive diffuse intrinsic pontine glioma.

INTRODUCTION: This study investigates the safety, tolerability, and preliminary efficacy of combined treatment with VEGF inhibitor bevacizumab, topoisomerase I inhibitor irinotecan, and EGFR inhibitor erlotinib in children with progressive diffuse intrinsic pontine glioma (DIPG). METHODS: Biweekly bevacizumab (10 mg/kg) and irinotecan (125 mg/m2) were combined with daily erlotinib. Two cohorts received increasing doses of erlotinib (65 and 85 mg/m2) following a 3 + 3 dose-escalation schedule, until disease progression with a maximum of one year. Dose-limiting toxicities (DLT) were monitored biweekly. Secondary progression free survival (sPFS) and overall survival (OS) were determined based on clinical and radiological response measurements. Quality of life (QoL) during treatment was also assessed. RESULTS: Between November 2011 and March 2018, nine patients with disease progression after initial radiotherapy were enrolled. Median PFS at start of the study was 7.3 months (range 3.5-10.0). In the first dose cohort, one patient experienced a DLT (grade III acute diarrhea), resulting in enrollment of three additional patients in this cohort. No additional DLTs were observed in consecutive patients receiving up to a maximum dose of 85 mg/m2. Median sPFS was 3.2 months (range 1.0-10.9), and median OS was 13.8 months (range 9.3-33.0). Overall QoL was stable during treatment. CONCLUSIONS: Daily erlotinib is safe and well tolerated in doses up to 85 mg/m2 when combined with biweekly bevacizumab and irinotecan in children with progressive DIPG. Median OS of the study patients was longer than known form literature.

Pharmacogenetic interactions in amyotrophic lateral sclerosis: a step closer to a cure?

Genetic mutations related to amyotrophic lateral sclerosis (ALS) act through distinct pathophysiological pathways, which may lead to varying treatment responses. Here we assess the genetic interaction between C9orf72, UNC13A, and MOBP with creatine and valproic acid treatment in two clinical trials. Genotypic data was available for 309 of the 338 participants (91.4%). The UNC13A genotype affected mortality (p = 0.012), whereas C9orf72 repeat-expansion carriers exhibited a faster rate of decline in overall (p = 0.051) and bulbar functioning (p = 0.005). A dose-response pharmacogenetic interaction was identified between creatine and the A allele of the MOBP genotype (p = 0.027), suggesting a qualitative interaction in a recessive model (HR 3.96, p = 0.015). Not taking genetic information into account may mask evidence of response to treatment or be an unrecognized source of bias. Incorporating genetic data could help investigators to identify critical treatment clues in patients with ALS.

Incisional Hernia Repair of Medium- and Large-Sized Defects: Laparoscopic IPOM Versus Open SUBLAY Technique.

Background: Small incisional hernias can be repaired laparoscopically with low morbidity and reasonable recurrence rates. The aim of this study was to compare laparoscopic with open technique in medium- and large-sized defects regarding postoperative complications and recurrence rates. Methods: Between 2012 and 2016, 102 patients with medium- or large-sized defects according to EHS classification underwent incisional hernia repair. Patients' characteristics, hernia size and postoperative complications were prospectively recorded. In October 2016, eligible patients were assessed for recurrence. Results: About 31 patients underwent laparoscopic IPOM and 71 patients open SUBLAY repair. Morbidity rate was significantly lower in IPOM group than in SUBLAY group (19% versus 41%; p = .028). Postoperative complications according to Clavien-Dindo classification were significantly lower in the IPOM group (p = .021). Duration of surgery (88 versus 114 min; p = .009) and length of hospital stay (five versus eight days; p < .001) were significantly shorter for IPOM than for SUBLAY. 71 patients were available for follow-up. Recurrence rates showed no significant difference between study groups (13% versus 7%, p = .508). Conclusions: Laparoscopic repair in medium- and large-sized defects is a feasible and safe approach. IPOM compared to SUBLAY significantly reduces postoperative complications and hospital stay; recurrence rates are comparable.

Importance of Pancreatic Enzyme Replacement Therapy after Surgery of Cancer of the Esophagus or the Esophagogastric Junction.

After surgical treatment of cancer of the esophagus or the esophagogastric junction we observed steatorrhea, which is so far seldom reported. We analyzed all patients treated in our rehabilitation clinic between 2011 and 2014 and focused on the impact of surgery on digestion of fat. Reported steatorrhea was anamnestic, no pancreatic function test was made. Here we show the results from 51 patients. Twenty-three (45%) of the patients reported steatorrhea. Assuming decreased pancreatic function pancreatic enzyme replacement therapy (PERT) was started or modified during the rehabilitation stay (in the following called STEA+). These patients were compared with the patients without steatorrhea and without PERT (STEA-). Maximum weight loss between surgery and rehabilitation start was 18 kg in STEA+ patient and 15.3 kg in STEA- patients. STEA+ patients gained more weight under PERT during the rehabilitation phase (3 wk) than STEA- patients without PERT (+1.0 kg vs. -0.3 kg, P = 0.032). We report for the first time, that patients after cancer related esophageal surgery show anamnestic signs of exocrine pancreas insufficiency and need PERT to gain body weight.

Correction to: A phase I/II study of gemcitabine during radiotherapy in children with newly diagnosed diffuse intrinsic pontine glioma.

In Table 2 of the original publication, there were errors in the baseline scores for the PedsQL TM 3.0 Cancer Module questionnaire, so a corrected version of Table 2 is shown in this erratum. In the subcategories of the PedsQL TM 3.0 Cancer Module questionnaire, nausea and fear of procedure did not score significantly lower after treatment compared to baseline. So, based on the corrected data in Table 2, there was no significant decrease in the total score of the cancer questionnaire, and this statement in the previous manuscript was incorrect.

Autoantibody pathogenicity in a multifocal motor neuropathy induced pluripotent stem cell-derived model.

OBJECTIVE: We investigated the pathogenicity of immunoglobulin M (IgM) anti-GM1 antibodies in serum from patients with multifocal motor neuropathy (MMN) using human induced pluripotent stem cell (iPSC)-derived motor neurons (MNs). METHODS: iPSCs were generated from fibroblasts and differentiated into MNs. We studied the binding of IgM to MNs, their complement-activating properties, and effects on structural integrity using fluorescence and electron microscopy. Live cell imaging was used to study effects of antibody binding on MNs in the presence and absence of complement. RESULTS: IgM antibody binding to MNs was detected using sera from MMN patients with and without detectable anti-GM1 IgM antibody titers in enzyme-linked immunosorbent assay, but not with sera from (disease) controls. Competition and depletion experiments showed that antibodies specifically bound to GM1 on iPSC-derived MNs. Binding of these antibodies disrupted calcium homeostasis by both complement-dependent and complement-independent pathways. MNs showed marked axonal damage after complement activation, and reduced antibody pathogenicity following treatment with immunoglobulin preparations. INTERPRETATION: Our data provide evidence for the pathogenicity of anti-GM1 IgM antibodies in MMN patients and link their presence to the clinical characteristics of axonal damage and immunoglobulin responsiveness. This iPSC-derived disease model will facilitate diagnosis, studies on autoantibody pathogenicity, drug development, and screening in immune-mediated neuropathies. Ann Neurol 2016;80:71-88.

A phase I/II study of gemcitabine during radiotherapy in children with newly diagnosed diffuse intrinsic pontine glioma.

The purpose of this phase I/II, open-label, single-arm trial is to investigate the safety, tolerability, maximum tolerated dose and preliminary efficacy of the potential radiosensitizer gemcitabine, administered concomitantly to radiotherapy, in children with newly diagnosed diffuse intrinsic pontine glioma (DIPG). Six doses of weekly gemcitabine were administered intravenously, concomitantly to 6 weeks of hyperfractionated radiotherapy. Successive cohorts received increasing doses of 140, 175 and 200 mg/m2 gemcitabine, respectively, following a 3 + 3 dose-escalation schedule without expansion cohort. Dose-limiting toxicities (DLT) were monitored during treatment period. Clinical response was assessed using predefined case report forms and radiological response was assessed using the modified RANO criteria. Quality of life (QoL) was assessed using PedsQL questionnaires. Between June 2012 and December 2016, nine patients were enrolled. Treatment was well tolerated, and no DLTs were observed up to the maximum dose of 200 mg/m2. All patients experienced reduction of tumor-related symptoms. QoL tended to improve during treatment. PFS and MOS were 4.8 months (95% CI 4.0-5.7) and 8.7 months (95% CI 7.0-10.4). Classifying patients according to the recently developed DIPG survival prediction model, intermediate risk patients (n = 4), showed a PFS and MOS of 6.4 and 12.4 months, respectively, versus a PFS and MOS of 4.5 and 8.1 months, respectively, in high risk patient (n = 5). Gemcitabine up to 200 mg/m2/once weekly, added to radiotherapy, is safe and well tolerated in children with newly diagnosed DIPG. PFS and MOS were not significantly different from literature.

External validation of the diffuse intrinsic pontine glioma survival prediction model: a collaborative report from the International DIPG Registry and the SIOPE DIPG Registry.

We aimed to perform external validation of the recently developed survival prediction model for diffuse intrinsic pontine glioma (DIPG), and discuss its utility. The DIPG survival prediction model was developed in a cohort of patients from the Netherlands, United Kingdom and Germany, registered in the SIOPE DIPG Registry, and includes age <3 years, longer symptom duration and receipt of chemotherapy as favorable predictors, and presence of ring-enhancement on MRI as unfavorable predictor. Model performance was evaluated by analyzing the discrimination and calibration abilities. External validation was performed using an unselected cohort from the International DIPG Registry, including patients from United States, Canada, Australia and New Zealand. Basic comparison with the results of the original study was performed using descriptive statistics, and univariate- and multivariable regression analyses in the validation cohort. External validation was assessed following a variety of analyses described previously. Baseline patient characteristics and results from the regression analyses were largely comparable. Kaplan-Meier curves of the validation cohort reproduced separated groups of standard (n = 39), intermediate (n = 125), and high-risk (n = 78) patients. This discriminative ability was confirmed by similar values for the hazard ratios across these risk groups. The calibration curve in the validation cohort showed a symmetric underestimation of the predicted survival probabilities. In this external validation study, we demonstrate that the DIPG survival prediction model has acceptable cross-cohort calibration and is able to discriminate patients with short, average, and increased survival. We discuss how this clinico-radiological model may serve a useful role in current clinical practice.

Human pontine glioma cells can induce murine tumors.

Diffuse intrinsic pontine glioma (DIPG), with a median survival of only 9 months, is the leading cause of pediatric brain cancer mortality. Dearth of tumor tissue for research has limited progress in this disease until recently. New experimental models for DIPG research are now emerging. To develop preclinical models of DIPG, two different methods were adopted: cells obtained at autopsy (1) were directly xenografted orthotopically into the pons of immunodeficient mice without an intervening cell culture step or (2) were first cultured in vitro and, upon successful expansion, injected in vivo. Both strategies resulted in pontine tumors histopathologically similar to the original human DIPG tumors. However, following the direct transplantation method all tumors proved to be composed of murine and not of human cells. This is in contrast to the indirect method that included initial in vitro culture and resulted in xenografts comprising human cells. Of note, direct injection of cells obtained postmortem from the pons and frontal lobe of human brains not affected by cancer did not give rise to neoplasms. The murine pontine tumors exhibited an immunophenotype similar to human DIPG, but were also positive for microglia/macrophage markers, such as CD45, CD68 and CD11b. Serial orthotopic injection of these murine cells results in lethal tumors in recipient mice. Direct injection of human DIPG cells in vivo can give rise to malignant murine tumors. This represents an important caveat for xenotransplantation models of DIPG. In contrast, an initial in vitro culture step can allow establishment of human orthotopic xenografts. The mechanism underlying this phenomenon observed with direct xenotransplantation remains an open question.

Personalised medicine in juvenile dermatomyositis: From novel insights in disease mechanisms to changes in clinical practice.

Juvenile dermatomyositis is characterized by childhood-onset chronic inflammation of the muscles and skin, with potential involvement of other organs. Patients are at risk for long-term morbidity due to insufficient disease control and steroid-related toxicity. Personalised treatment is challenged by a lack of validated tools that can reliably predict treatment response and monitor ongoing (subclinical) inflammation, and by a lack of evidence regarding the best choice of medication for individual patients. A better understanding of the involved disease mechanisms could reveal potential biomarkers and novel therapeutic targets. In this review, we highlight the most relevant immune and non-immune mechanisms, elucidating the effects of interferon overexpression on tissue alongside the interplay between the interferon signature, mitochondrial function, and immune cells. We review mechanism-based biomarkers that are promising for clinical implementation, and the latest advances in targeted therapy development. Finally, we discuss key steps needed for translating these discoveries into clinical practice.

Pharmacokinetics and Pharmacodynamics of Systemic Corticosteroids in Autoimmune and Inflammatory Diseases: A Review of Current Evidence.

BACKGROUND AND OBJECTIVE: Systemic corticosteroids have a long history of use in the treatment of autoimmune and inflammatory diseases. Both efficacy and safety show large interindividual variability (IIV), suggesting that corticosteroids may have the potential for individualised dosing strategies to optimise therapy. This systematic review aims to provide an overview of current evidence on the pharmacokinetic (PK) and pharmacodynamic (PD) relationships of systemic corticosteroids in patients with autoimmune and inflammatory diseases. METHODS: A systematic literature search was conducted in PubMed and Embase for PK/PD studies of systemic corticosteroids in autoimmune and inflammatory diseases in humans published until December 2023. Studies were scored from 1 to 5 according to criteria for the levels of evidence, as inspired by the Oxford Centre for Evidence-Based Medicine. RESULTS: Twelve studies (1981-2016) were included. The majority of these studies had a small sample size. The corticosteroids involved were prednisone, prednisolone, methylprednisolone and budesonide. Substantial IIV of corticosteroid PK was described in all studies. Evidence for a relationship between the PK of corticosteroids and efficacy was inconclusive and limited. However, there was some evidence for a relationship between the PK of prednisolone and the severity of Cushingoid features. CONCLUSION: There is insufficient evidence to draw firm conclusions on the potential associations between PK and clinical outcome of systemic corticosteroid treatment in autoimmune and inflammatory diseases. This is remarkable given the many decades that steroid drugs have been used in clinical care. Prospective research is recommended with robust and well-defined cohorts to fully quantify the PK/PD associations of corticosteroids.

Brain MRI White Matter Abnormalities in Pediatric Non-Infectious Uveitis.

BACKGROUND: Childhood chronic non-infectious uveitis (cNIU) is a challenging disease whose differential diagnosis may include demyelinating diseases. We aim to describe the white matter abnormalities (WMA) in brain MRI in childhood cNIU. METHODS: This is a multicentric retrospective study involving children with cNIU followed at the Pediatric rheumatology units of Florence and the ophthalmology department of the UMC Utrecht who underwent a Brain MRI. Demographic, clinical, laboratory and imaging information was collected. The presence of WMA was considered as the main outcome. RESULTS: Data of 123 children was collected (66 from Utrecht and 57 from Florence), of whom 51 were males, with a median uveitis onset at age 9 years (range 3-16) for the UMC Utrecht and 8.75 years (range 1.6-15.1) for Florence. We evaluated 39 children with anterior uveitis, 35 with intermediate uveitis, 1 with posterior uveitis and 48 with panuveitis. Uveitis was idiopathic in 105. On brain MRI, 33 patients (26.8%) showed WMA, and most of them had non-anterior uveitis (72.8%). WMA were more frequent in males (χ2 5.25, p = 0.02). No difference in underlying systemic disease was seen between patients with and without WMA, but 40% of patients with TINU and 27.3% of patients with idiopathic uveitis showed WMA. None of the patients received a diagnosis of demyelinating disease during follow-up. CONCLUSION: As WMA were found in 26.8% of patients who were screened in our cohort, brain MRI might be useful in cNIU. However, the clinical significance of these WMA could not be determined in this study. An interdisciplinary evaluation is necessary to assess the appropriate management, and a longer follow up is necessary to determine the prognosis of some of these WMA.

Recombinant Interleukin-1 Receptor Antagonist Is an Effective First-Line Treatment Strategy in New-Onset Systemic Juvenile Idiopathic Arthritis, Irrespective of HLA-DRB1 Background and IL1RN Variants.

OBJECTIVE: Human leukocyte antigen (HLA)-DRB1*15:01 has been recently associated with interstitial lung disease (LD), eosinophilia, and drug reactions in systemic juvenile idiopathic arthritis (sJIA). Additionally, genetic variants in IL1RN have been linked to poor response to anakinra. We sought to reproduce these findings in a prospective cohort study of patients with new-onset sJIA treated with anakinra as first-line therapy. METHODS: HLA and IL1RN risk alleles were identified via whole-genome sequencing. Treatment responses and complications were compared between carriers versus noncarriers. RESULTS: Seventeen of 65 patients (26%) carried HLA-DRB1*15:01, comparable with the general population, and there was enrichment for HLA-DRB1*11:01, a known risk locus for sJIA. The rates of clinical inactive disease (CID) at 6 months, 1 year, and 2 years were generally high, irrespective of HLA-DRB1 or IL1RN variants, but significantly lower in carriers of an HLA-DRB1*11:01 allele. One patient, an HLA-DRB1*15:01 carrier, developed sJIA-LD. Of the three patients with severe drug reactions to biologics, one carried HLA-DRB1*15:01. The prevalence of eosinophilia did not significantly differ between HLA-DRB1*15:01 carriers and noncarriers at disease onset (6.2% vs 14.9%, P = 0.67) nor after the start of anakinra (35.3% vs 37.5% in the first 2 years of disease). CONCLUSION: We observed high rates of CID using anakinra as first-line treatment irrespective of HLA-DRB1 or IL1RN variants. Only one of the 17 HLA-DRB1*15:01 carriers developed sJIA-LD, and of the three patients with drug reactions to biologics, only one carried HLA-DRB1*15:01. Although thorough monitoring for the development of drug hypersensitivity and refractory disease courses in sJIA, including sJIA-LD, remains important, our data support the early start of biologic therapy in patients with new-onset sJIA irrespective of HLA-DRB1 background or IL1RN variants.

Humoral and cellular immunogenicity, effectiveness and safety of COVID-19 mRNA vaccination in patients with pediatric rheumatic diseases: A prospective cohort study.

OBJECTIVES: To evaluate immunogenicity, effectiveness and safety of COVID-19 vaccination in patients with pediatric autoimmune inflammatory rheumatic disease (pedAIIRD). METHODS: A prospective cohort study was performed at the pediatric rheumatology department of the Wilhelmina Children's Hospital in Utrecht, the Netherlands. Vaccination dates, COVID-19 cases and vaccine-related adverse events (AEs) were registered for all pedAIIRD patients during regular clinic visits from March 2021 - August 2022. SARS-CoV-2 IgG antibody levels and T-cell responses were measured from serum samples after vaccination, and clinical and drug therapy data were collected from electronic medical records. Rate of COVID-19 disease was compared between vaccinated and unvaccinated patients in a time-varying Cox regression analysis. RESULTS: A total of 157 patients were included in this study and 88 % had juvenile idiopathic arthritis (JIA). One hundred thirty-seven patients were fully vaccinated, of which 47 % used biological agents at the time of vaccination, and 20 patients were unvaccinated. Geometric mean concentrations (GMCs) of post-vaccine antibody levels against SARS-CoV-2 were above the threshold for positivity in patients who did and did not use biological agents at the time of vaccination, although biological users demonstrated significantly lower antibody levels (adjusted GMC ratio: 0.38, 95 % CI: 0.21 - 0.70). T-cell responses were adequate in all but two patients (9 %). The adjusted rate of reported COVID-19 was significantly lower for fully vaccinated patients compared to non-vaccinated patients (HR: 0.53, 95 % CI: 0.29 - 0.97). JIA disease activity scores were not significantly different after vaccination, and no serious AEs were reported. CONCLUSIONS: COVID-19 mRNA vaccines were immunogenic (both cellular and humoral), effective and safe in a large cohort of pedAIIRD patients despite their use of immunosuppressive medication.

The protective effect of COVID-19 vaccines on developing multisystem inflammatory syndrome in children (MIS-C): a systematic literature review and meta-analysis.

OBJECTIVE: To review whether the current COVID-19 vaccines can prevent the occurrence of multisystem inflammatory syndrome in children (MIS-C) and adolescents. METHODS: A systematic literature review and meta-analysis were performed. The data were abstracted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Primary outcome was the efficacy of COVID-19 vaccination in preventing MIS-C development. The search was performed in PubMed and Embase. RESULTS: The review yielded 13 studies, which were included for critical appraisal and data extraction. The available studies showed a reduced incidence of MIS-C after mRNA COVID-19 vaccination in children aged 12-18 years. Four studies were eligible for meta-analysis and the pooled odds ratio for MIS-C in vaccinated children compared to unvaccinated children was 0.04 (95% confidence interval: 0.03-0.06). Additionally, the risk of MIS-C as an adverse effect of vaccination was much lower compared to the risk of MIS-C post-infection. CONCLUSIONS: Our systematic review highlights the current available evidence on the efficacy of COVID-19 vaccination in preventing MIS-C. The published studies so far - mainly conducted during the Delta wave - indicate that (original strain) COVID-19 mRNA vaccines in children are safe and associated with significantly less development of MIS-C. These findings further reinforce the recommendation for COVID-19 vaccination in children, which should be promoted and largely supported.

Long-term immunoprotection after live attenuated measles-mumps-rubella booster vaccination in children with juvenile idiopathic arthritis.

INTRODUCTION: Vaccines, especially live attenuated vaccines, in children with JIA pose a great challenge due to both potential lower immunogenicity and safety as a result of immunosuppressive treatment. For many years, in the Netherlands, JIA patients receive a measles-mumps-rubella (MMR) booster vaccine at the age of nine years as part of the national immunization program. OBJECTIVES: To study long-term humoral immunoprotection in a large cohort of JIA patients who received the MMR booster vaccine while being treated with immunomodulatory therapies at the Wilhelmina Children's Hospital in Utrecht, the Netherlands. METHODS: MMR-specific IgG antibody concentrations in stored serum samples of vaccinated JIA patients were determined with chemiluminescent microparticle immunoassays (CMIA). Samples were analyzed five years after MMR booster vaccination and at last available follow-up visit using both crude and adjusted analyses. Additional clinical data were collected from electronic medical records. RESULTS: In total, 236 samples from 182 patients were analyzed, including 67 samples that were available five years post-vaccination, and an additional 169 samples available from last visits with a median duration after vaccination of 6.9 years (IQR: 2.8-8.8). Twenty-eight patients were using biologic disease-modifying antirheumatic drugs (bDMARDS) of whom 96% anti-TNF agents and 4% tocilizumab. Percentages of protective antibody levels against measles after five years were significantly lower for patients who used bDMARD therapy at vaccination compared to patients who did not: 60% versus 86% (P = 0.03). For mumps (80% versus 94%) and rubella (60% versus 83%) this difference did not reach statistical significance (P = 0.11 and P = 0.07, respectively). Antibody levels post-vaccination decreased over time, albeit not significantly different between bDMARD users and non-bDMARD users. CONCLUSION: The MMR booster vaccine demonstrated long-term immunogenicity in the majority of children with JIA from a large cohort, although lower percentages of protective measles antibody levels were observed in bDMARD users. Hence, it might be indicated to measure antibody levels at least five years after MMR booster vaccination in the latter group and advice an extra booster accordingly.

Safety of Measles-Mumps-Rubella booster vaccination in patients with juvenile idiopathic arthritis: A long-term follow-up study.

OBJECTIVES: To study short and long-term disease activity and vaccine-related adverse events in a cohort of JIA patients who received the live attenuated measles-mumps-rubella (MMR) booster vaccine while being treated with immunosuppressive and immunomodulatory therapies. METHODS: A retrospective study was performed in the UMC Utrecht, clinical and therapeutic data were collected from electronic medical records for two visits before and two visits after the MMR booster vaccine of JIA patients. Drug therapy was collected and adverse events related to the vaccine were requested from the patients during clinical visits or by short phone interviews. Associations between MMR booster vaccination and the active joint count, physician global assessment of disease activity, patient-reported visual analogue scale (VAS) for well-being and clinical Juvenile Arthritis Disease Activity Score (cJADAS) were analyzed using multivariable linear mixed effects analyses. RESULTS: A total of 186 JIA patients were included in the study. At the time of vaccination, 51% of the patients used csDMARD and 28% used bDMARD therapy. Overall, adjusted disease activity scores after MMR booster vaccination were not significantly different compared to pre-vaccination. Mild adverse events related to the MMR booster were reported for 7% of the patients. No serious adverse events were reported. CONCLUSION: MMR booster vaccination was safe and did not worsen disease activity during long-term follow-up in a large cohort of JIA patients being treated with both csDMARDs and biological DMARDs.

Meningococcal ACWY conjugate vaccine immunogenicity in adolescents with primary or secondary immune deficiencies, a prospective observational cohort study.

BACKGROUND: Immunization with meningococcal ACWY conjugate vaccine induces protective antibodies against invasive meningococcal disease (IMD) caused by serogroups A, C, W and Y. We studied MenACWY-TT vaccine immunogenicity in adolescents with a heterogenous group of primary and secondary immune deficiency including patients with systemic lupus erythematosus, mixed connective tissue disease, vasculitis, uveitis, 22Q11 syndrome, sickle cell disease, and patients who underwent stem cell transplantation for bone marrow failure. FINDINGS: We enrolled 69 individuals aged 14-18 years diagnosed with a primary or secondary immune deficiency in a prospective observational cohort study. All patients received a single dose of MenACWY-TT vaccine during the catch-up campaign 2018-19 because of the IMD-W outbreak in the Netherlands. Capsular polysaccharide-specific (PS) IgG concentrations against MenACWY were measured before and 3-6, 12, and 24 months after vaccination. Overall, geometric mean concentrations (GMCs) of MenACWY-PS-specific IgG were lower in patients compared to data from healthy, aged-matched controls (n = 75) reaching significance at 12 months postvaccination for serogroup A and W (adjusted GMC ratios 0.26 [95% CI: 0.15-0.47] and 0.22 [95% CI: 0.10-0.49], respectively). No serious adverse events were reported by study participants. CONCLUSIONS: The MenACWY conjugate vaccine was less immunogenic in adolescent patients with primary or secondary immunodeficiency compared to healthy controls, urging the need for further surveillance of these patients and supporting considerations for booster MenACWY conjugate vaccinations in these patient groups.