Search

Background Galactosialidosis (GS) is a rare inherited lysosomal storage disorder (LSD) which is characterized by a defect in the lysosomal glycoprotein catabolism. We report, for the first time, the case of a child affected by GS presenting with recurrent episodes of extensive joint inflammation in both knee joints. The aim of this case-report is to describe the clinical presentation as well as the laboratory, radiologic and microscopic features of this unique presentation of GS. Furthermore, we explore inflammatory mechanisms potentially responsible for the origination of the arthritic joint pathology observed in our patient. Case presentation We describe the rare case of a 12-year-old boy diagnosed with GS (late infantile form) who presented with multiple episodes of inflammatory arthritis involving both knees; no other joints were suspected for joint inflammation. Laboratory results did not indicate an autoimmune disorder. Synovial fluid tested negative for any bacterial infection and ruled out a malignancy and crystal-induced arthritis. Microscopic examination of the synovial tissue revealed numerous foamy macrophages with extensive vacuolization, consistent with the previous diagnosis of GS. Treatment consisted of aspiration of excessive joint fluid and subsequent intra-articular injection of triamcinolonhexacetonide with excellent but transient result. Given the evidence of storage products within macrophages of the inflamed synovial tissue and the absence of other etiological clues, GS itself was considered as the primary cause for the relapsing inflammatory joint pathology. According to the restricted data on articular manifestations in GS, to date, GS cannot be linked directly to joint inflammation. Nevertheless, in several other LSDs, the accumulation of storage material has been associated with numerous osteoimmunological changes that might play a role in the pathophysiology of arthritic processes. Conclusions We hypothesize that the articular build-up of GS storage products triggered systemic as well as local inflammatory processes, resulting in the extensive inflammatory joint pathology as observed in our patient. Future identification of other patients with GS is required to corroborate the existence of an arthritic clinical phenotype of GS and to assess the underlying pathophysiology.

Background Anti-tumor necrosis factor (TNF) drugs have improved the prognosis for juvenile idiopathic arthritis (JIA) significantly. However, evidence for individual treatment decisions based on serum anti-TNF drug levels and the presence of anti-drug antibodies (ADAbs) in children is scarce. We aimed to assess if anti-TNF drug levels and/or ADAbs influenced physician’s treatment decisions in children with JIA. Methods Patients’ records in our center were retrospectively screened for measurements of anti-TNF drug levels and ADAbs in children with JIA using etanercept, adalimumab or infliximab. Clinical characteristics and disease activity were retrieved from patient charts. Results We analyzed 142 measurements of anti-TNF drug levels in 65 children with JIA. Of these, ninety-seven (68.3%) were trough concentrations. N = 14/97 (14.4%) of these showed trough concentrations within the therapeutic drug range known for adults with RA and IBD. ADAbs against adalimumab were detected in seven patients and against infliximab in one patient. Seven (87,5%) of these ADAb-positive patients had non-detectable drug levels. A flowchart was made on decisions including rational dose escalation, stopping treatment in the presence of ADAbs and undetectable drug levels, showing that 45% of measurements influenced treatment decisions, which concerned 65% of patients (n = 42/65). Conclusions In the majority of patients, measurement of anti-TNF drug levels led to changes in treatment. A wide variation of anti-TNF drug levels was found possibly due to differences in drug clearance in different age groups. There is need for determination of therapeutic drug ranges and pharmacokinetic curves for anti-TNF and other biologics in children with JIA.

Background: Clinical phenotyping and predicting treatment responses in Systemic Lupus Erythematosus (SLE) patients is challenging. Extensive blood transcriptional profiling has identified various gene modules that are promising for stratification of SLE patients. We aimed to translate existing transcriptomic data into simpler gene signatures suitable for daily clinical practice. Methods: RT-PCR of multiple genes from the Interferon M1·2, Interferon M5·12, neutrophil (NPh) and plasma cell (PLC) modules followed by a principle component analysis, was used to identify indicator genes per gene signature. Gene signatures were measured in longitudinal samples from two childhood onset SLE cohorts (n=101 and n=34, respectively) and associated with clinical features. Disease activity was measured using SELENA-SLEDAI. Cluster analysis subdivided patients into three mutually exclusive fingerprint-groups termed 1) all-signatures-low, 2) only IFN high (M1·2 and/or M5·12) and 3) high NPh and/or PLC. Findings: All gene signatures were significantly associated with disease activity in cross-sectionally collected samples. The PLC-signature showed the highest association with disease activity. Also, in longitudinally collected samples, the PLC signature was associated with disease activity and showed a decrease over time. When patients were divided into fingerprints, the highest disease activity was observed in the high NPh and/or PLC group. The lowest disease activity was observed in the all-signatures-low group. The same distribution was reproduced in samples from an independent SLE cohort. Interpretation: The identified gene signatures are associated with disease activity and suitable tools to stratify SLE patients into groups with similar activated immune pathways that may guide future treatment choices. Funding: Sophia Children’s Hospital Fund, NVLE (Dutch patient organization for Lupus, APS, Scleroderma and MCTD) and Dutch Arthritis Society Declaration of Interest: SK received funding from GlaxoSmithKline outside the submitted work. All other authors declare no competing interests. Ethical Approval: Written informed consent was obtained from all participants in compliance with the Declaration of Helsinki. The study was approved by the ethics committee of each institution.

Background:Systemic lupus erythematosus (SLE) is a severe, lifelong autoimmune disease known for its multisystem organ involvement. SLE patients are known to be at risk for premature atherosclerosis at a relatively young age (1). Endothelial dysregulation is one of the pathophysiologic mechanisms that can lead to the higher risk for cardiovascular disease in SLE (2). Multiple endothelial markers with dysregulation in SLE have been described so far, of which some are associated with disease activity.Objectives:To report a systematic literature review regarding endothelial markers that are dysregulated in SLE and search for associations with disease activity.Methods:The search was performed according to the Preferred Reporting Items for Systematic review and Meta-analysis Protocols (PRISMA-P) 2015 (3). In July 2020, the search terms were used in Embase, MEDLINE, Web of Science, Google Scholar and Cochrane. Inclusion criteria were 1) published studies after the year 2000 that reported measurements of endothelial cell markers in serum and/or plasma of SLE patients (diagnosed according to ACR/SLICC criteria), 2) English language peer reviewed articles and 3) disease activity measurement (i.e. SLEDAI, BILAG, SLAM, ECLAM or PGA). Exclusion criteria were 1) case reports or editorials, 2) studies performed in animals and 3) studies with microRNA/cytokine biomarkers. There was no minimum count for study population. The screening process is shown in figure 1.Results:From 1892 hits, we identified 110 eligible articles. Table 1 shows an overview of the most frequently studied endothelial markers. These identified endothelial markers are involved in endothelial cell (EC) activation, EC apoptosis, disturbed angiogenesis, defective vascular tone control, immune dysregulation and coagulopathy. In most studies, dysregulation of the endothelial marker was associated with disease activity. The majority of the studies had a cross-sectional design, longitudinal data on endothelial markers in SLE are scarce.Conclusion:We identified multiple endothelial markers that are dysregulated in SLE and this dysregulation was often associated with disease activity in cross-sectional studies. Our future plan is to test the identified endothelial markers in (longitudinally collected) samples of (childhood onset) SLE patients, disease- and healthy controls. This will be a next step in unravelling the pathophysiology of premature atherosclerosis and cardiovascular events in SLE-patients in young adulthood.Figure 1.References:[1]Vavlukis M, Pop-Gjorceva D, Poposka L, Sandevska E, Kedev S. Myocardial Infarction in Systemic Lupus Erythematosus - the Sex Specific Risk Profile. Curr Pharm Des. 2020 Dec 9.[2]Westerweel PE, Luyten RK, Koomans HA, Derksen RH, Verhaar MC. Premature atherosclerotic cardiovascular disease in systemic lupus erythematosus. Arthritis Rheum. 2007 May;56(5):1384-96.[3]Shamseer L, Moher D, Clarke M, Ghersi D, Liberati A, Petticrew M, Shekelle P, Stewart LA; PRISMA-P Group. Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015: elaboration and explanation. BMJ. 2015 Jan 2;350:g7647.Table 1.Endothelial markerArticles(no. of studies)Significant correlation with SLEDAI(no. of studies)Studies with control groups(no. of studies)Longitudinal data(no. of studies)YesNoUnknownHealthy controlsDiseased controlsVCAM-12620152338VEGF2213542022ICAM-11811521734Thrombomodulin1710521322E-Selectin136521021MCP-18620712P-Selectin6321611IP-106510501Pentraxin-35500512vWF5410502Neopterin3210202Fas3021201Angiopoeietin-2330021-Endothelin-1312030-PAI-1311120-Adrenomedullin320120-TWEAK311112-PECAM-1311130-Disclosure of Interests:None declared

Background To evaluate radiographic progression of patients with new-onset juvenile idiopathic arthritis (JIA) in response to an early, tightly-controlled, treatment-to-target. Methods Patients with JIA participating in the BeSt-for-Kids-study, randomized to 3 treatment strategy arms, were eligible if at least 1 conventional wrist-radiograph was available. Bone damage as reflected by carpal length was assessed using the Poznanski-score. The BoneXpert-method was used to determine the Bone Age (BA, > 5 years) and bone mineral density (BMD) of the wrist. These scores were evaluated over time and compared between the treatment arms and mean JADAS10-score using linear mixed models corrected for age and symptom duration. Results In 60 patients, 252 radiographs were analysed. Baseline age and symptom duration were different between the arms. No difference in comparison to the healthy reference population was found at baseline for the Poznanski-score (IQR varying from − 0,82; 0.68), nor for BA (varying from − 0.88 to 0.74). Baseline BMD was statistically significantly lower in arm 3 (initial treatment with etanercept and methotrexate) (− 1.48; − 0.68) compared to arm 1 (− 0.84; − 0.04) and arm 2 (− 0.93; 0.15). After treatment to target inactive disease, the Poznanski-scores and the BA remained clinically unchanged, while the BMD in arm 3 improved (p

Background:Higher dosage regimes for Infliximab (IFX) have been described to be effective in partial- or non-responding adults and children with rheumatic disease and appear to be safe (1,2). To optimize IFX treatment in juvenile idiopathic arthritis (JIA) patients, therapeutic drug monitoring (TDM) might be beneficial. To support routine TDM of IFX and dose regimen optimization in JIA patients, more in-depth knowledge of the pharmacokinetic (PK) variability of IFX is needed. Ultimately, as soon as the optimal therapeutic drug ranges will be known, PK model-based simulation can be used to individualize drug dosing recommendations. Individual dosages may be adjusted by taking specific patient characteristics into account that explain inter-patient variability in pharmacokinetics (PK). Inter-patient variability can be quantified and investigated by the population approach.Objectives:Our hypothesis is that optimizing dosage and frequency of IFX administration for individual patients will improve treatment outcome. In this current study, the population PK for IFX are described for JIA patients.Methods:Data including IFX trough concentrations and anti-IFX antibodies of 27 JIA patients on IFX maintenance treatment were retrieved from electronic charts. Three population pharmacokinetic models from literature were validated for our dataset using nonlinear-mixed effects modeling program NONMEM (3,4,5). A novel population pharmacokinetic model was developed based on our study data.Results:A total of 65 obtained blood samples after a median of 32 days after the last IFX infusion (IQR 28-42) were analyzed. The three published models underpredicted the observed trough concentrations. A newly developed one compartment model best described the IFX serum concentration over time data in JIA patients (see Figure 1).Conclusion:Our study shows a novel and the first PK model for IFX in JIA patients. Our main finding was that a one- compartment model best described the IFX serum concentration over time data. Predictive performance of the known models from literature was insufficient for our patient data. Our data also show that different PK models are needed for different age categories (children or adults) and in different diseases.References:[1]Nozaki Y et al. Infliximab dose adjustment can improve the clinical and radiographic outcomes of rheumatoid arthritis patients: REVIVE study results. Biologics. 2018.[2]Tambralli A et al. High doses of infliximab in the management of juvenile idiopathic arthritis. J Rheumatol. 2013.[3]Fasanmade AA et al. Pharmacokinetic properties of infliximab in children and adults with Crohn’s disease: a retrospective analysis of data from 2 phase III clinical trials. Clin Ther. 2011.[4]Xu Z et al. Population pharmacokinetics of infliximab in patients with ankylosing spondylitis. J Clin Pharmacol. 2008.[5]Ternant D et al. Relationship between inflammation and infliximab pharmacokinetics in rheumatoid arthritis. Br J Clin Pharmacol. 2014.Table 1.Patient characteristicsN=27 patientsWeight (kg)52 [40 – 62]BSA1.6 [1.3 – 1.8]Age (years)14 [11 – 17]Male, N (%)6 (22%)CRP (mg/L)0.5 [0.2 – 0.7]WBC count6.5 [5.6 –7.5]Antibodies-to-IFX1 (4%)Dose (mg)300 [200-400]Dose (mg/kg)5.4 [4.9 -7.0]Hemoglobine (mmol/L)7.9 [7.5 -8.2]ESR (mm/h)5 [5-8]Uveitis3 (11%)Disclosure of Interests:None declared.

Background:Juvenile Idiopathic Arthritis (JIA) is the most common auto-immune disease in children and pain is a common symptom. Despite treatment advances in recent years, pain often persists when the disease is inactive. Treating JIA to target has been widely recommended1, but effectiveness in pain reduction has not been proven yet2.Objectives:To compare pain scores over two years in three treatment arms in JIA patients that were treated to target and to identify baseline characteristics predicting unfavorable pain outcomes.Methods:DMARD naïve children who participated in the BeSt for kids study3 with oligoarticular JIA, RF negative polyarticular JIA and juvenile psoriatic arthritis were included. Patient were treated to target aimed at inactive disease according to 1 of 3 different treatment groups; 1) initial sequential DMARD monotherapy 2) initial methotrexate (MTX) with prednisolone bridging or 3) initial MTX with etanercept. Pain intensity was measured using a 100 mm Visual Analogue Scale during 24 months of follow up with 3-monthly intervals. Potential differences in VAS pain scores over time between treatment arms were compared using linear mixed models with random intercept and random slope for visits clustered within patients. A similar multivariable mixed model was used to assess the ability of several baseline characteristics to predict the chance of high pain levels during follow-up.Results:92 patients were randomized into the three treatment groups. Overall, pain scores over time reduced from mean 55.3 (SD 21.7) at baseline to 19.5 (SD 25.3) after 24 months. When comparing pain over time per arm, pain scores decreased significantly over time β -1.37 (95% CI -1.726; -1.022). No significant difference was found in pain over time between treatment groups (interaction term treatment arm*time (months) β (95% CI) arm 1 0.13 (-0.36; 0.62) and arm 2 0.37 (-0.12; 0.86) compared to arm 3), Figure 1. Correction for sex and symptom duration as possible confounders yielded similar results. Multiple baseline characteristics demonstrated a significant predictive value for pain over time: VAS pain (scale 0-100) with β 0.44 (95% CI 0.25; 0.65), VAS physician (scale 0-100) with β -0.34 (-0.55; -0.06), number of active joints with β 0.77 (0.19; 1.34), Child Health Questionnaire Physical summary Score with β -0.42 (-0.72; -0.11) and Psychosocial summary Score β -0.42 (-0.77; -0.06). Symptom duration, VAS patient/parent and NSAID use were no significant predictors, Table 1.Conclusion:Treatment to target seems effective in pain reduction in non-systemic JIA patients irrespective of initial treatment strategy. Several baseline predictors for pain over time were identified, which could serve as an initial indication for non-systemic JIA-patients with a high risk of pain despite a strict treat-to-target strategy.References:[1]Ravelli A, Consolaro A, Horneff G, et al. Treating juvenile idiopathic arthritis to target: recommendations of an international task force. Ann Rheum Dis. 2018;77(6):819–828.[2]Schoemaker, C.G., Swart, J.F. & Wulffraat, N.M. Treating juvenile idiopathic arthritis to target: what is the optimal target definition to reach all goals?. Pediatr Rheumatol. 18, 34 (2020)[3]Hissink Muller P, Brinkman DMC, Schonenberg-Meinema D, et al. Treat to target (drug-free) inactive disease in DMARD-naive juvenile idiopathic arthritis: 24-month clinical outcomes of a three-armed randomised trial. Ann Rheum Dis. 2019 Jan;78(1):51-59.Table 1.Baseline Characteristicsβp-value95% Confidence IntervalVAS Pain0.450.0000.25 to 0.65VAS Physician-0.310.014-0.55 to -0.06VAS Patient/parent-0.020.873-0.21 to 0.18No. of active joints0.770.0090.19 to 1.34PhS*-0.420.008-0.72 to -0.11PsS**-0.420.022-0.77 to -0.06Symptom duration (mo.)8.090.118-2.08 to 18.26NSAID use-1.300.791-10.91 to 8.31VAS Pain, VAS physician and VAS patient/parent was measures on a 100mm scale.*PhS= Physical Summary Score of the Child Health Questionnaire Parent form 50 (scale 0-100).**PsS= Psychosocial Summary Score of the CHQ-PF50 (scale 0-100).Disclosure of Interests:None declared

Background:Even in the hands of experienced clinicians, clinical phenotyping and predicting treatment responses in Systemic Lupus Erythematosus (SLE) patients remains challenging. Therefore, the identification of biomarkers that can help physicians to divide patients into subgroups based upon aberrantly activated pathways is relevant and might guide future treatment strategies. Extensive blood transcriptional profiling has identified various gene modules that seem promising for stratification of SLE patients into subgroups (1). However, the feasibility to implement these complicated and expensive tests for use in the daily practice of routine clinical laboratories is challenging if not impossible.Objectives:The aim of this study was to develop gene signatures that stratify patients into groups with comparable disease profiles and are feasible to perform in routine clinical laboratories.Methods:To identify coordinated expression of a set of genes and reduce data complexity, genes from 4 previously described modules (Interferon M1.2, Interferon M5.12, Neutrophil- and Plasmablast (PB)(1)) were measured using real-time quantitative PCR expression on whole blood RNA samples. Subsequently, a principle component analysis was used to select 2-5 indicator genes, that represent a specific signature. Expression levels of these genes were measured in healthy donors (n=42) and samples from two independent childhood-onset SLE cohorts (n=51 and n=20). Scores higher than the mean + 2 S.D. score of healthy controls were defined as high gene signature scores. Based on their expression levels, gene signatures were divided over 14 clusters. Associated clusters were subsequently grouped into three gene fingerprints termed 1) all-signatures-low, 2) only high IFN (M1.2 and/or M5.12) and 3) high PB and/or Neutrophil. Disease activity was measured by the SELENA-SLEDAI score.Results:All four gene signatures were higher expressed in patients compared to healthy controls and showed a significant correlation with the SLEDAI. The PB signature showed the highest association with disease activity (r= 0.6512, PConclusion:Various gene signatures are associated with disease activity, which underlines the involvement of different pathophysiological mechanisms in SLE. Combining these signatures into gene fingerprints can help to stratify patients into comparable groups and guide individualized treatment choices for patients in the future.References:[1]Banchereau R, Hong S, Cantarel B, Baldwin N, Baisch J, Edens M, et al. Personalized Immunomonitoring Uncovers Molecular Networks that Stratify Lupus Patients. Cell. 2016;165(6):1548-50.Figure 1.SELENA-SLEDAI scores based on gene fingerprint distribution. Blue indicates time point one of cohort 1 (n=51); pink indicates time point two of cohort 1 (n=45); red indicates time point one of the replication cohort (n=20)Disclosure of Interests:None declared

Background:It has been suggested that a capillary scleroderma pattern in patients with systemic lupus erythematosus (SLE)-patients predisposes for clinical signs of systemic sclerosis (SSc) or overlap disease (1). However, this was previously shown not to be the case in a cross-sectional study in childhood-onset SLE (cSLE) (2).Objectives:To assess if nailfold capillary patterns in cSLE change over time and if a capillary scleroderma pattern is associated with prospective development of clinical SSc-features, higher SLE disease activity or –damage.Methods:Prospective clinical and capillaroscopy data were used from a longitudinal cohort of cSLE patients. Patients with a disease onset before the age of 18 years and diagnosis according to SLICC 2012 criteria were included. Disease activity was defined by SLEDAI score and disease damage by the SLICC damage index. Nailfold images from eight fingers (excluding thumbs) were obtained by videocapillaroscopy. A scleroderma pattern was defined according to the ‘fast track algorithm’ (3). An abnormal capillary pattern that did not match the criteria for a scleroderma pattern was defined as ‘microangiopathy’.Results:Our longitudinal study cohort consisted of n=53 cSLE patients with a median disease onset of 14 years (IQR 12.5-15.5 years) and a median SLEDAI score at diagnosis of 11 (IQR 8-15.5). Clinical follow-up data were available from 0.5-16 years after disease onset. Median disease duration at first capillaroscopy was 17 months (IQR 5.5-51.5 months) and 17/53 (32.1%) of patients had Raynaud’s phenomenon. In total, n=9 (17%) showed a scleroderma pattern (at some point in time), n=37 (70%) had microangiopathy and n=7 (13%) showed a normal capillary pattern. N=27 patients had follow up with capillaroscopy (1-7 times over 1-5 years). In most patients (23/27) we did not observe any change in capillary pattern during follow-up. Two patients showed changes from microangiopathy to a scleroderma pattern, one patient from a scleroderma pattern to microangiopathy and one patient from microangiopathy to a normal pattern. Raynaud’s phenomenon was equally distributed among patients with different capillaroscopy patterns (p=0.487), as was median SLEDAI score at diagnosis (p=0.285). Follow-up patients with a capillary scleroderma pattern did not show any clinical features for SSc over time (follow-up over 1-5 years, Table 1 below. Patients with a capillary scleroderma pattern showed significantly more disease damage (Chi-square, p=0.008), also indicated by a survival analysis for disease damage (Figure 1, p=0.042).Conclusion:Our study indicates that a capillary scleroderma pattern in cSLE correlates with disease damage but not with clinical SSc features during follow-up period.References:[1]S. Pavlov-Dolijanovic et al. Is there a difference in systemic lupus erythematosus with and without Raynaud’s phenomenon? Rheum Int 2013;33: 859–865[2]D. Schonenberg-Meinema et al. Nailfold capillary abnormalities in childhood-onset systemic lupus erythematosus. Revised manuscript after review re-submitted to Lupus in January 2021[3]V. Smith et al. Fast track algorithm. Autoimm Rev 2019 Nov;18(11): 102394Table 1.Clinical characteristics of cSLE-patients (n=9/53) with a nailfold capillary scleroderma patternButterfly rashPhotosensitive rashLupus nephritisAutoimmune cytopeniaPositive CoombsLow C3/C4SerositisDamageType of auto-antibodiesFollow-up in years1++-+++-+ANA, Anti-ds-DNA, anti-Sm, anti-RNP, anti-Ro52, anti-SS-A52++-+++-+ANA, Anti-ds-DNA, anti-Sm, anti-RNP, anti-SS-A53-+++++++ANA, Anti-ds-DNA, anti-Sm, anti-RNP, anti-SS-A104-++-++++ANA, Anti-ds-DNA, anti-Sm, anti-RNP, anti-Ro52, anti-SS-A95-+--+-+-ANA1 (lost)6-++++++-ANA, Anti-ds-DNA, anti-c1q37---+----ANA, Anti-ds-DNA, anti-Sm, anti-RNP18++-+----ANA99-+++++++ANA, Anti-ds-DNA, anti-RNP, anti-SS-A8Figure 1.Occurrence of disease damage (with survival as ‘no damage’) in cSLE patients with microangiopathy (blue) and a capillary scleroderma pattern (red)Disclosure of Interests:None declared

Background Rituximab (RTX) is increasingly used in rheumatologic,1, 2 hematologic3 and renal diseases.4 The induced B cell depletion can lead to hypogammaglobulinemia and thus an increased risk of infection.5 B cell depletion is not always achieved, and this has a negative effect on therapeutic response.6 Anaphylaxis is a frequent side effect of RTX and has been associated with the occurrence of anti-drug antibodies (ADA) against RTX.7 Objectives To describe in different paediatric patient groups the pharmacodynamics of RTX in children by outcome variables, i.e. success of B-cell depletion and time of B cell repopulation, as well as the risk factors for severe infections and anaphylaxis. Methods Patient data of children who received RTX between 2008 and 2017 at our centre were retrospectively collected. Three patient subgroups were defined: autoimmune diseases (AID), immune dysregulation (ID) and renal diseases (RD). B cell repopulation was defined as a number above the cut-off value of B cell depletion (=0.050*10^6/l or Results B cell measurements were performed in 53/55 patients. B cell depletion was not achieved in 9 patients. In the 35 patients with B cell repopulation, median time until repopulation was 155 days (IQR 105–222): in the AID group (n=12) 129 days (IQR 77.5–243, p=0.363), in the ID group (n=5) 172 days (IQR 154–181, p=0.574) and in the RD group (n=18) 163 days (IQR 121–229, p=0.847). After RTX treatment, in 36 patients IgG levels were measured of which 14 (39%) had low IgG levels on at least one occasion (median 7 g/L [range 0.6–38.1 g/L]). Severe infections leading to hospitalisation occurred in 15 (27%) cases. An allergic reaction during or directly after RTX infusion was observed in 27 patients (49%). Anaphylaxis, defined as a systemic allergic reaction, characterised by impairment of airway, breathing, circulation or consciousness, occurred in 10 of these patients (18% of total cohort). Seven patients were tested for anti-RTX antibodies of whom 6 tested positive: 5 patients in the AID-group and one patient with renal disease. Allergic reactions occurred in all 6 while RTX failed to induce B cell depletion in 4 of these. Conclusions Time-to-B-cell-repopulation after RTX did not significantly differ between different paediatric patients groups. Severe infections were common (27%) in the cohorts studied. It is unclear from our data whether this is merely related to RTX treatment. Presence of ADA against RTX seems to predict failure of B-cell depletion and/or anaphylaxis after RTX treatment. References [1] de Lemos LL, et al. Rev Bras Reumatol2014;54(3):220–30. [2] Sanz I. Nat Rev Rheumatol2016;12(12):700–2. [3] Omri HE, et al. Clin Med Insights Blood Disord2015;8:1–7. [4] Fervenza FC, et al. Clin J Am Soc Nephrol2010;5(12):2188–98. [5] Lahiri M, et al. Best Pract Res Clin Rheumatol2015;29(2):290–305. [6] Thiel J, et al. Arthritis Res Ther2017;19(1):101. [7] Einarsson JT, et al. Clin Rheumatol2017; Dec;36(12):2743–2750. Disclosure of Interest None declared

Background In rheumatoid arthritis treatment, targeted treatment has shown to improve disease outcomes including the option of drug tapering and discontinuation. In non-systemic juvenile idiopathic arthritis (nsJIA) this has not been tried in a trial. Objectives To investigate which of three treatment strategies, targeting at drug-free inactive disease, is most effective and safe in recent onset DMARD-naive nsJIA. Methods We conducted a randomised, multicenter, treatment strategy study with 24 months of follow up. Patients, 2–16 years old with symptom duration Results 94 children (67% girls) with a median (InterQuartile Range) age of 9.1 (4.6–12.9) years were enrolled: 32 in arms 1 and 2, 30 in arm 3. Eleven had oligo-articular JIA, n=73 polyarticular JIA and n=8 juvenile psoriatic arthritis, 37% were ANA positive. At baseline VAS physician was median (IQR) 50 39–58 mm, VAS patient 54 37–70 mm, ESR 6 (2–14) mm/hr, active joints 8, 5–12 limited joints 2.5 (1–5), and CHAQ score 0.9 (0.6–1.5). After 24 months 61% (arm 1), 63% (arm 2) and 61% (arm 3) of patients had inactive disease and 45% (arm 1) 31% (arm 2) and 38% (arm 3) had stopped all DMARD(s). Time to inactive disease (median 9.0 (6.0–12.0) months) was not significantly different between arms, nor was time to flare (18.0 (15.0–21.0) months). Adapted ACRpedi-scores were comparably high between arms. Functional ability improved and remained almost normal. Toxicity reports showed mild events in similar rates across all arms. Results after 24 months by GEE. Conclusions Treatment to target drug free inactive disease is feasible in recent onset non-systemic JIA, resulting, regardless of initial treatment, in over 60% of patients in inactive disease and 38% drug free. Disclosure of Interest None declared

Background Juvenile idiopathic arthritis (JIA) is the most prevalent paediatric rheumatic disease.1 Long term complications include physical disability and a decreased quality of life.2,3 Since the introduction of anti-TNF drugs for JIA, its prognosis has improved significantly.1 Personalised medicine is the next step to improve treatment in JIA. Anti-TNF trough levels and demonstration of the presence of anti-drug antibodies (ADA) could help individualise treatment decisions in JIA patients, but evidence supporting this is missing. Objectives To describe cross-sectional data of anti-TNF trough levels and ADA, combined with decision effects, in children with JIA. Methods Patients‘ records in children with JIA using etanercept, adalimumab or infliximab were retrospectively checked for measurements of anti-TNF trough levels and ADA. Anti-TNF trough concentrations and ADA were measured using an enzyme-linked immunosorbent assay (ELISA) and antigen-binding test. Data on age, sex, JIA subtype, reason for testing and the decision effect of trough level or presence of ADA on the current therapy were collected. Results Eighty-one anti-TNF trough levels were measured in 45 children with JIA. A wide variety of anti-TNF trough levels was found. Therapeutic drug concentrations, according to adult ranges in RA and IBD,4,5,6 were found in 11 (58%) patients on etanercept (n=19), 2 (14%) on adalimumab (n=14) and 8 (17%) on infliximab (n=48). Four patients on adalimumab and one patient on infliximab showed ADA. All of these five patients had non-detectable drug trough levels. Reasons for testing trough level and/or presence of ADA were loss of response (20%), partial or no response (40%), measurement after dosage increase (2%), remission (17%), uveitis flare (9%) and allergic reaction (11%). Treatment decisions were influenced by trough levels in 70/81 (86.4%) of measurements and in 5/5 (100%) of patients with ADA. Conclusions Measuring anti-TNF trough levels and ADA was a valuable tool in making personalised treatment decisions in JIA. Treatment changes included dose/frequency increase, or stopping and switching treatment in the presence of ADA combined with undetectable drug levels. More data are needed to access optimal therapeutic drug levels in anti-TNF treatment in JIA and to implement this strategy more widely. References [1] Blazina S, et al. Paediatr Drugs2016;18(6):397–412. [2] Tambralli A, et al. J Rheumatol2013;40(10):1749–55. [3] Haverman L, et al. Rheumatology (Oxford)2012;51(2):368–74. [4] Kneepkens EL, et al. Ann Rheum Dis2015;74(10):1825–9. [5] Pouw MF, et al. Ann Rheum Dis2015;74(3):513–8. [6] Singh N, Dubinsky DC. Gastroenterol Hepatol (NY)2015;11(1): 48–55. Disclosure of Interest None declared

Combination therapy with prednisone or etanercept may induce earlier and/or more improvement in disease activity in Disease Modifying Anti Rheumatic Drug (DMARD) naive non-systemic Juvenile Idiopathic Arthritis (JIA) patients. Here we present three months clinical outcome of initial treatments of the BeSt-for-Kids study. Included patients were randomized to either: 1. initial DMARD-monotherapy (sulfasalazine (SSZ) or methotrexate (MTX)), 2. Initial MTX / prednisolone-bridging, 3. Initial combination MTX/etanercept. Percentage inactive disease, adjusted (a) ACR Pedi30, 50 and 70 and JADAS after 6 and 12 weeks of treatment (intention to treat analysis) and side effects are reported. 94 patients (67% girls, 32 (arm 1), 32 (arm 2) and 30 (arm 3) with median (InterQuartileRange) age of 9.1 (4.7-12.9) years were included. 38% were ANA positive, 10 had oligo-articular disease, 68 polyarticular JIA and 16 psoriatic arthritis. Baseline median (IQR) ACRpedi-scores: VAS physician 49 (40-58) mm, VAS patient 54 (37-70) mm, ESR 6.5 (2-14.8)mm/hr, active joint count 8 (5-12), limited joint count 3 (1-5), CHAQ score 0.88 (0.63-1.5). In arm 1, 17 started with MTX, 15 with SSZ. After 3 months, aACR Pedi 50 was reached by 10/32 (31%), 12/32(38%) and 16/30 (53%) (p = 0.19) and aACR Pedi 70 was reached by 8/32 (25%), 6/32(19%) and 14/30(47%) in arms 1-3 (p = 0.04). Toxicity was similar. Few serious adverse events were reported. After 3 months of treatment in a randomized trial, patients with recent-onset JIA achieved significantly more clinical improvement (aACRPedi70) on initial combination therapy with MTX / etanercept than on initial MTX or SSZ monotherapy. NTR1574 . Registered 3 December 2008.

Objective Children with juvenile idiopathic arthritis (JIA) experience functional impairment due to joint manifestations of the disease. The aim of our present study was to assess health-related quality of life (HRQOL) and its predictors in a group of children and adolescents with JIA. Methods The study sample includes all JIA patients (ages 6–18 years) who consulted a pediatric rheumatologist in Amsterdam, The Netherlands, between February 2009 and March 2010. HRQOL was measured using the Paediatric Quality of Life Inventory 4.0 (ages 6–18 years). Functional ability was measured using the Childhood Health Assessment Questionnaire, and medical and sociodemographic parameters were assessed. The study sample was compared to a Dutch youth norm population including children with other chronic health conditions. The proportion of children with JIA with an impaired HRQOL (

Artemis deficiency is known to result in classical T-B- severe combined immunodeficiency (SCID) in case of Artemis null mutations, or Omenn's syndrome in case of hypomorphic mutations in the Artemis gene. We describe two unrelated patients with a relatively mild clinical T-B- SCID phenotype, caused by different homozygous Artemis splice-site mutations. The splice-site mutations concern either dysfunction of a 5' splice-site or an intronic point mutation creating a novel 3' splice-site, resulting in mutated Artemis protein with residual activity or low levels of wild type (WT) Artemis transcripts. During the first 10 years of life, the patients suffered from recurrent infections necessitating antibiotic prophylaxis and intravenous immunoglobulins. Both mutations resulted in increased ionizing radiation sensitivity and insufficient variable, diversity and joining (V(D)J) recombination, causing B-lymphopenia and exhaustion of the naive T-cell compartment. The patient with the novel 30 splice-site had progressive granulomatous skin lesions, which disappeared after stem cell transplantation (SCT). We showed that an alternative approach to SCT can, in principle, be used in this case; an antisense oligonucleotide (AON) covering the intronic mutation restored WT Artemis transcript levels and non-homologous end-joining pathway activity in the patient fibroblasts. Genes and Immunity (2011) 12, 434-444; doi:10.1038/gene.2011.16; published online 10 March 2011

Background Siblings with cystic fibrosis (CF) share many genetic and environmental factors but may present different phenotypes. Younger sibs are mostly earlier diagnosed with CF than their older sibs, but might be at risk for an earlier colonization with Pseudomonas aeruginosa (PA) than their older counterparts due to cross-infection within families. Aims To analyze the effects of birth order and age at diagnosis on lung function, PA colonization, nutritional status, and survival during the first two decades of life in siblings with CF. Methods A retrospective cohort study of 52 sibling pairs was performed in two Dutch CF centers. Data were analyzed both cross-sectionally and longitudinally using Kaplan–Meier curves and modified log-rank tests. Results Median age at diagnosis was significantly higher in the older sib compared with the younger sib (3.0 and 0.2 years, respectively, P

Item does not contain fulltext OBJECTIVE: The aim of this study was to determine the genetic and immunological defects underlying familial manifestations of an autoimmune disorder. METHODS: Whole-exome sequencing was performed on the index patient with various manifestations of autoimmunity, including hypothyroidism, vitiligo and alopecia. Peripheral blood mononuclear cells and DNA of family members were used for functional and genetic testing of the candidate variants obtained by Sanger sequencing. RESULTS: Exome sequencing identified 233 rare, coding and nonsynonymous variants in the index patient; five were highly conserved and affect genes that have a possible role in autoimmunity. Only a heterozygous missense mutation in the suppressor of cytokine signalling 4 gene (SOCS4) cosegregated with the autoimmune disorder in the family. SOCS4 is a known inhibitor of epidermal growth factor (EGF) receptor signalling, and functional studies demonstrated specific upregulation of EGF-dependent immune stimulation in affected family members. CONCLUSION: We present a family with an autoimmune disorder, probably resulting from dysregulated immune responses due to mutations in SOCS4.

Contains fulltext : 153727.pdf (Publisher’s version ) (Closed access) PURPOSE: To analyze the data of the national registry of all Dutch primary immune deficiency (PID) patients, according to the European Society for Immunodeficiencies (ESID) definitions. RESULTS: In the Netherlands, 745 patients had been registered between 2009 and 2012. An overall prevalence of 4.0 per 100,000 inhabitants was calculated. The most prevalent PID was 'predominantly antibody disorder (PAD)' (60.4%). In total, 118 transplantations were reported, mostly hematopoietic stem cell transplantations (HSCT). Almost 10% of the PID patients suffered from a malignancy, in particular 'lymphoma' and 'skin cancer'. Compared to the general Dutch population, the relative risk of developing any malignancy was 2.3-fold increased, with a >10-fold increase for some solid tumors (thymus, endocrine organs) and hematological disease (lymphoma, leukemia), varying per disease category. CONCLUSIONS: The incidence rate and characteristics of PID in the Netherlands are similar to those in other European countries. Compared to the general population, PID patients carry an increased risk to develop a malignancy.

In juvenile idiopathic arthritis (JIA) patients there is a lack of markers that predict severe disease. Although anticitrullinated protein antibodies (ACPA) have contributed substantially to the understanding of rheumatoid arthritis (RA),1 their detection in JIA has not been equally useful as incidence rates in JIA patients are low2 and merely confined to the polyarticular immunoglobulin (Ig)M-rheumatoid factor (RF)-positive category resembling RA. Recently, anticarbamylated protein (anti-CarP) antibodies were detected in 45% of RA patients and importantly also in 16%–20% ACPA-negative patients.3–5 Within the ACPA-negative patients, anti-CarP antibodies were associated with more severe radiographic progression.3 Since most JIA patients are ACPA-negative we investigated whether anti-CarP antibodies are present in the sera of JIA patients and how they are related to ACPA and IgM-RF. JIA patients from three Dutch sources were included: the BeSt for Kids trial (NTR 1574, a treatment strategy study) (n=33), a previously described cohort6 (n=48) and the Arthritis and Biologicals in Children (ABC) register7 (n=153). Healthy controls (n=107) (mean age/range 11/(2–20)) are stem-cell graft …

SummaryPlatelet-activating factor (PAF) is a proinflammatory agent in infectious and inflammatory diseases, partly due to the activation of infiltrating phagocytes. PAF exerts its actions after binding to a monospecific PAF receptor (PAFR). The potent bioactivity is reflected by its ability to activate neutrophils at picomolar concentrations, as defined by changes in levels of intracellular Ca2+ ([Ca2+]i), and induction of chemotaxis and actin polymerization at nanomolar concentration. The role of PAF in neutrophil survival is, however, less well appreciated.In this study, the inhibitory effects of synthetic PAFR-antagonists on various neutrophil functions were compared with the effect of recombinant human plasma-derived PAF-acetylhydrolase (rPAF-AH), as an important enzyme for PAF degradation in blood and extracellular fluids. We found that endogenously produced PAF (–like) substances were involved in the spontaneous apoptosis of neutrophils. At concentrations of 8 µg/ml or higher than normal plasma levels, rPAF-AH prevented spontaneous neutrophil apoptosis (21 ± 4% of surviving cells (mean ± SD; control) versus 62 ± 12% of surviving cells (mean ± SD; rPAF-AH 20 µg/ml); P In conclusion, the efficient and stable enzymatic activity of rPAF-AH over so many hours of coculture with neutrophils demonstrates the potential for its use in the many inflammatory processes in which PAF (–like) substances are believed to be involved.

Treatment of juvenile idiopathic arthritis (JIA) has changed dramatically since the introduction of biologics in 1999. Because of more insight in the cytokines involved in JIA the number of available biologic agents increased. Together with the introduction of these new drugs, new insights in the optimal treatment of JIA indicate that earlier and more aggressive therapy is associated with better outcomes. Whether these developments with regard to biologic treatment have resulted in better patients' outcomes in daily practice is not yet reported.

Churg-Strauss syndrome (CSS) is a rare systemic vasculitis of the small- and medium-size vessels. It is mostly seen in elderly patients presenting as de novo asthma, eosinophilia, and vasculitic organ involvement. In childhood, CSS is extremely rare. The course of pediatric CSS is usually severe and often lethal. We present a case of a 13-year-old girl with a short history of asthma, marked eosinophilia, and multiorgan involvement. The extremely high level of blood eosinophilic granulocytes (51.6 × 10(9)/L) prompted a workup for eosinophilic leukemia before the diagnosis CSS could be made. Subsequently, the disease was successfully treated. This case report shows a classical case of childhood CSS, remarkable because of the presence of extreme hypereosinophilia. It underlines the importance of CSS as a life-threatening cause of hypereosinophilia in children.

Hypochlorous (HOCl) and hypobromous (HOBr) acids are strong oxidants derived from myeloperoxidase and eosinophil peroxidase, the major antimicrobial enzymes of neutrophils and eosinophils, respectively. These oxidants are highly reactive with a wide range of biomolecules. At physiological pH, both HOCl and HOBr react readily with amines to form haloamines and with the unsaturated bonds of fatty acids to form halohydrins. We have investigated which of these reactions occur with phosphatidylethanolamine (PE), the predominant phospholipid of Escherichia coli. The formation of haloamines was determined by TLC and colorimetrically and the formation of halohydrins was determined by TLC and GC-MS. With HOCl, chloramines were much the preferred product and chlorohydrins were formed in substantial amounts only when HOCl was in excess of the amount required to convert the amine to the dichloramine. With HOBr at all concentrations, bromamines and bromohydrins were formed concurrently, indicating a greater relative reactivity with unsaturated fatty acids than with HOCl. The bromamine derivatives of PE, and other primary amines, were found to be more reactive than the equivalent chloramines, and were able to brominate the unsaturated bonds of fatty acids. Bromohydrins (formed directly or through the action of bromamines) may, therefore, be suitable biomarkers for the production of HOBr in vivo.

Neutrophils and monocytes produce the highly cytotoxic hypochlorous acid (HOCl) via the myeloperoxidase (MPO)-catalyzed reaction of H2O2 with Cl-. We have investigated the reaction of reagent and MPO-derived HOCl with cholesterol in a purified liposome system, as well as progressively more complex biological systems. The products were identified by thin-layer chromatography (TLC) and characterized by mass spectrometry (MS). TLC of the HOCl-treated samples gave four major cholesterol products with color development typical of oxysterols. Two of the products coeluted with authentic alpha- and beta-chlorohydrin standards. As was the case with the standards, they were readily converted into their respective epoxides during analysis by MS. Gas chromatography-mass spectrometry analysis of the other major product (band 3) gave peaks consistent with epoxides as well as a lateeluting peak with a distinct mass spectrum. Electrospray MS of this product confirmed its identity as a chlorohydrin based on the presence of the predicted molecular ion and 3:1 Cl isotope ratios. Lipids extracted from red cells and isolated red cell membranes were exposed to HOCl and gave identical products to the purified cholesterol liposome system as determined by TLC and MS. Higher concentrations of HOCl were required due to competition by other unsaturated lipids and protein molecules. When intact red cells, neutrophils, and MCF7 mammary carcinoma cells were exposed to HOCl, cholesterol chlorohydrins were formed, as detected by TLC. The formation of cholesterol chlorohydrins could be potentially disruptive to cell membranes and result in cell lysis and death. They could also be potential biomarkers for oxidative damage associated with neutrophil/monocyte activation.

Results 262 previously biologic-naive JIA-patients initiated etanercept; 71% female, 18% systemic-onset subtype. Median age at onset 6.9 (IQR 3.6-11.1) years, median followup 35.6 (IQR 17.4-53.6) months. In the long-term, the overall majority responded to etanercept and up to 40% reached inactive disease. Excellent response after 15 months (85 patients, 32%) was associated with low baseline disability (OR 0.49/point increase, 95%CI 0.33-0.74), fewer DMARDs used before etanercept (OR 0.64/ DMARD used, 95%CI 0.43-0.95) and younger age at onset (OR 0.92/year, 95%CI 0.84-0.99); poor response (88 patients, 34%) was associated with female gender (OR 2.12, 95%CI 1.11-4.08) and systemic-onset subtype (OR 3.24, 95%CI 1.39-7.56). However, 24% of systemiconset patients reached excellent response. Reasons for discontinuation: ineffectiveness in 78, adverse events (AEs) in 25, remission in 39 patients. Etanercept was well tolerated. Patients who developed AEs could not be identified at baseline.

Met lit. opg

Met lit. opg

Lit.opg., bijl.

Met lit. opg

To provide a detailed description of the time course and the site specificity of hydroperoxide-induced oxidative stress in red blood cells (RBCs), we have characterized the action of a membrane-soluble (cumene hydroperoxide [cumOHH]) and a water-soluble (hydrogen peroxide [H 2 O 2 ]) oxidant. The fluorescent polyunsaturated fatty acid (PUFA) parinaric acid (PnA) was used to probe peroxidation processes in the membrane, and oxidation of hemoglobin (Hb) was measured spectrophotometrically as an indicator of cytosolic oxidative stress. The observed degradation patterns of PnA and Hb were clearly distinct for each oxidant. At comparable oxidant concentrations, the cumulative oxidative stress on the RBC membrane was always much higher with cumOOH, whereas much more Hb oxidation was measured with H 2 O 2 . The kinetics of Hb oxidation as well as the nature of the products formed were different for each oxidant. The main Hb oxidation product generated gradually by cumOOH was metHb, whereas H 2 O 2 caused the rapid formation of ferrylHb. ComOOH caused more oxidation of endogenous PUFAs and of vitamin E, while the degradation pattern of vitamin E closely resembled that of PnA. At high oxidant concentrations, extensive cell lysis was observed after prolonged incubation. Butylated hydroxytoluene (BHT) completely prevented oxidation of endogenous PUFAs but did not completely prevent hemolysis, indicating that factors other than lipid peroxidation are also important in causing lysis of RBCs. The action of cumOOH is characterized by a gradual reaction with Hb, generating radicals that produce an oxidative stress primarily directed at the membrane, which increases in time to a maximum and then gradually decreases. In contrast, H 2 O 2 crosses the RBC membrane and reacts rapidly with Hb, generating a very reactive radical species that has Hb, not the membrane, as a prime target. H 2 O 2 -induced oxidative stress is at a maximum immediately after addition of this oxidant and decreases rapidly to zero in a short time. These findings provide further insight into the mode of action of hydrperoxides and the mechanism of compartmentalization of RBC oxidative damage.

Lit.opg., bijl.

Lit.opg., bijl.

Met lit. opg

Met lit. opg

Lit.opg., bijl.

Met lit. opg

Met lit. opg

Lit.opg., bijl.

In view of a possible relationship between fish oil, lipid peroxidation, and atherosclerosis, the in vitro lipid peroxidation susceptibility of red blood cells (RBCs) from rabbits on conventional (-FO) and fish oil-enriched diets (+FO) was investigated. The diet caused substantial increases in the RBC concentrations of n-3 polyunsaturated fatty acids (PUFAs), in combination with decreases in the concentration of oleic acid (18:1) and linoleic acid (18:2). Cumene hydroperoxide-induced oxidative stress led to increased overall fatty acid peroxidation in +FO RBCs compared with with -FO RBCs, as quantitated by GLC fatty acid analysis. However, the increased overall susceptibility to lipid peroxidation of +FO RBCs was not reflected in increased peroxidation of every individual fatty acid. This was observed for endogenous arachidonic acid (20:4) as well as, in separate experiments, for exogenously added parinaric acid (PnA). The increased cumene hydroperoxide-induced PUFA oxidation in +FO RBCs was accompanied by a lesser extent of hemolysis. To account for these observations, it is proposed that the increased n-3 PUFA content of +FO RBCs serves as an oxidizable buffer. The present data suggest that oxidation of fatty acids can occur until a critically low level of intact phospholipid in the RBC membrane is reached, after which the membrane destabilizes and hemolysis occurs. At the same time, the PUFA buffer in +FO RBCs could also prevent oxidative damage to specific membrane proteins, which could also help prevent cell lysis.