Blood brain barrier permeability and astrocyte-derived extracellular vesicles in children with juvenile idiopathic arthritis: a cross-sectional study.

BACKGROUND: Juvenile idiopathic arthritis (JIA) is the most prevalent rheumatic disease in children, and the inflammatory process is widely studied, primarily characterized by its impact on joint health. Emerging evidence suggests that JIA may also affect the central nervous system (CNS). This study investigates the potential CNS involvement in JIA by analyzing the presence of astrocyte-derived extracellular vesicles (EVs) and the S100B protein in plasma, both of which are indicative of astrocyte activity and blood-brain barrier (BBB) integrity. METHODS: EDTA plasma from 90 children diagnosed with JIA and 10 healthy controls, matched by age and gender, was analyzed for extracellular vesicles by flow cytometric measurement. Astrocyte-derived EVs were identified using flow cytometry with markers for aquaporin 4 (AQP-4) and glial fibrillary acidic protein (GFAP). Levels of the S100B protein were measured using a commercial ELISA. Disease activity was assessed using the Juvenile Arthritis Disease Activity Score (JADAS27, 0-57), and pain levels were measured using a visual analogue scale (VAS, 0-10 cm). RESULTS: Our analyses revealed a significantly higher concentration of astrocyte-derived EVs in the plasma of children with JIA compared with healthy controls. Furthermore, children with JADAS27 scores of 1 or higher exhibited notably higher levels of these EVs. The S100B protein was detectable exclusively in the JIA group. CONCLUSION: The elevated levels of astrocyte-derived EVs and the presence of S100B in children with JIA provide evidence of BBB disruption and CNS involvement, particularly in those with higher disease activity. These findings underscore the importance of considering CNS health in the comprehensive management of JIA. Further research is required to elucidate the mechanisms behind CNS engagement in JIA and to develop treatments that address both joint and CNS manifestations of the disease.

Disease activity trajectories from childhood to adulthood in the population-based Nordic juvenile idiopathic arthritis cohort.

OBJECTIVES: To identify long-term disease activity trajectories from childhood to adulthood by using the clinical Juvenile Arthritis Disease Activity Score (cJADAS10) in juvenile idiopathic arthritis (JIA). Second, to evaluate the contribution of the cJADAS10 components and explore characteristics associated with active disease at the 18-year follow-up. METHODS: Patients with onset of JIA in 1997-2000 were followed for 18 years in the population-based Nordic JIA cohort. We used a discrete mixture model for longitudinal clustering of the cJADAS10 and its components. We assessed factors potentially associated with higher scores on the patient's global assessment of well-being (PaGA) by hierarchical clustering and correlation analysis. RESULTS: Four disease activity trajectories were identified based on the cJADAS10 components among 427 patients. In trajectory-group 2, the PaGA and the physician's global assessment of disease activity (PhGA) increased significantly during the course, but not the active joint count. The increase in the PaGA was significantly higher than the increases in the PhGA and the active joint count (p<0.0001). A similar pattern was found among all the patients with active disease in the total cohort. Patients with higher PaGA scores had unfavourable scores on several other patient-reported outcomes. CONCLUSIONS: We have identified groups of patients based on long-term disease activity trajectories. In our study the PaGA was the most important driver of disease activity into adulthood assessed by cJADAS10. We need to better understand how our patients interpret global well-being and implement strategies to achieve inactive disease perceived both by the patient and the physician.

Body mass index is associated with health-related quality of life and disease characteristics in young adults with juvenile idiopathic arthritis.

BACKGROUND: There is a growing interest concerning the relationship between obesity and several medical conditions and inflammation. Nevertheless, there is a lack of studies regarding body mass index (BMI) among patients with juvenile idiopathic arthritis (JIA). Our aim was to investigate the impact of BMI on health-related quality of life (HRQoL) measured with a 36-Item Short Form Survey (SF-36), disease activity, and disability in young adults with JIA. METHODS: This study is a part of the population-based Nordic JIA cohort study. All newly diagnosed patients with JIA were recruited consecutively between 1997-2000 in specific regions in the Nordic countries. Patients in this sub-study were enrolled from 434 patients who attended their 18-year follow-up visit. Patients were classified according to the World Health Organization (WHO) into four groups based on their BMI. HRQoL, disease characteristics, disability, fatigue, sleep quality, physical activity, pain, comorbidities, and social status were assessed. RESULTS: Three hundred fifty-five patients from the original study cohort were enrolled in this study and 72% of them were female. Mean age was 23.9 (± SD 4.4) years. A significant relationship was found between the JIA categories and BMI groups (p = 0.014). A significant relationship was also found between BMI and disease activity scores (DAS28) (p = 0.028), disability (p < 0.001), pain (p = 0.013), fatigue (p = 0.035), and sleep quality (p = 0.044). Moreover, a significant relationship between BMI and HRQoL regarding bodily pain (p = 0.010) and general health (p = 0.048) was revealed when adjusted for sex, age, and JIA subtype. CONCLUSION: We discovered that BMI was significantly related to HRQoL, disease activity, and disability. BMI deserves more attention considering the treatment options and outcome of JIA in young adults.

A qualitative evaluation of the specific carbohydrate diet for juvenile idiopathic arthritis based on children's and parents' experiences.

BACKGROUND: Insights into the immunological role of the gastrointestinal tract in autoimmune conditions have led to the investigation of diet as a potential adjunctive treatment option for juvenile idiopathic arthritis (JIA). The specific carbohydrate diet (SCD) has shown promising results. However, studies on participants' experiences of dietary interventions in JIA are rare. In this study we investigated the experiences of children and parents' who had participated in a four-week intervention with SCD aiming to examine the potential anti-inflammatory effects. OBJECTIVES: To conduct a qualitative evaluation exploring children's and parents' experiences of the dietary intervention, how they navigated challenges, and their support requirements. METHODS: Semi-structured interviews were conducted with 12 children and 15 parents from 13 families, who were interviewed individually and together. The transcripts were analysed using systematic text condensation. RESULTS: Most participants interviewed found the intervention beneficial, with 12 out of 13 reporting positive effects, such as reduced pain and morning stiffness, and improved gastrointestinal function. Many participants reported being willing to repeat the intervention in the current form. Despite facing challenges, all children followed the diet for one to three months, with some continuing to follow a modified version. Facing the socio-emotional consequences of adhering to the diet was challenging for children. These were handled by focusing on the positive aspects and by relying on the supportive environment available. Parents struggled with practical issues since the diet required hard work, time, and money. Areas identified as requiring additional support include finding simple, quick, and child-friendly solutions, strengthening organizational food skills such as meal planning, and preparation prior to starting the intervention regarding socio-emotional aspects. CONCLUSION: Navigating the dietary treatment was considered challenging, practically for the parents and socio-emotionally for the children. Based on the reported challenges and participants' suggestions the intervention could be optimised by providing support and solutions in relation to the practical issues and better preparation regarding dealing with the socio-emotional consequences. Despite the difficulties, the participants reported overall positive experiences of, and attitudes towards, the current setup. Consequently, dietary interventions, such as the SCD, may be regarded as suitable targets for further research.

A novel serum calprotectin (MRP8/14) particle-enhanced immuno-turbidimetric assay (sCAL turbo) helps to differentiate systemic juvenile idiopathic arthritis from other diseases in routine clinical laboratory settings.

BACKGROUND: Differential diagnosis in children with signs of unprovoked inflammation can be challenging. In particular, differentiating systemic juvenile idiopathic arthritis (SJIA) from other diagnoses is difficult. We have recently validated the complex of myeloid-related proteins 8/14 (MRP8/14, also known as S100A8/A9 complex or serum calprotectin) as a helpful biomarker supporting the diagnosis of SJIA. The results were subsequently confirmed with a commercial ELISA. However, further optimization of the analytical technology is important to ensure its feasibility for large-scale use in routine laboratory settings. METHODS: To evaluate the accuracy in identifying children with SJIA, the performance of a particle-enhanced immuno-turbidimetric assay for serum calprotectin (sCAL turbo) on an automated laboratory instrument was analyzed. Samples from 615 children were available with the diagnoses SJIA (n = 99), non-systemic JIA (n = 169), infections (n = 51), other inflammatory diseases (n = 126), and acute lymphoblastic leukemia (ALL, n = 147). In addition, samples from 23 healthy controls were included. RESULTS: The sCAL turbo assay correlated well with the MRP8/14 ELISA used in previous validation studies (r = 0.99, p < 0.001). It could reliably differentiate SJIA from all other diagnoses with significant accuracy (cutoff at 10,500 ng/ml, sensitivity 84%, specificity 94%, ROC area under curve 0.960, p < 0.001). CONCLUSIONS: Serum calprotectin analyses are a helpful tool supporting the diagnosis of SJIA in children with prolonged fever or inflammatory disease. Here, we show that an immuno-turbidimetric assay for detection of serum calprotectin on an automated laboratory instrument can be implemented in clinical laboratory settings to facilitate its use as a diagnostic routine test in clinical practice.

Application and performance of disease activity indices proposed for patients with systemic sclerosis in an international cohort of patients with juvenile systemic sclerosis.

Objectives: Juvenile systemic sclerosis is a rare childhood disease. Three disease activity indices have been published for adult patients with systemic sclerosis: the European Scleroderma Study Group Index, a modified version of the European Scleroderma Study Group Index and the revised European Scleroderma Trials and Research index. The objective of this study was to determine the feasibility and performance of the three disease activity indices in a prospectively followed cohort of patients with juvenile systemic sclerosis. Methods: The analysis cohort was selected from the prospective international inception cohort enrolling juvenile systemic sclerosis patients. The correlation of the disease activity indices with the physicians' and the patients' global assessment of disease activity was determined. The disease activity indices were compared between patients with active and inactive disease. Sensitivity to change between 6- and 12-month follow-up was investigated by mixed models. Results: Eighty percent of the 70 patients had a diffuse cutaneous subtype. The revised European Scleroderma Trials and Research index was highly correlated with the physician-reported global disease activity/parents-reported global disease activity (r = 0.74/0.64), followed by the European Scleroderma Study Group activity index (r = 0.61/0.55) and the modified version of the European Scleroderma Study Group activity index (r = 0.51/0.43). The disease activity indices significantly differed between active and inactive patients. The disease activity indices showed sensitivity to change between 6- and 12-month follow-up among patients who improved or worsened according to the physician-reported global disease activity and the parents-reported global disease activity. Conclusion: Overall, no disease activity score is superior to the other, and all three scores have limitations in the application in juvenile systemic sclerosis patients. Furthermore, research on the concept of disease activity and suitable scores to measure disease activity in patients with juvenile systemic sclerosis is necessary in future.

An explorative study on proteomic analyses related to inflammation and pain in children with juvenile idiopathic arthritis.

BACKGROUND: Our aim was attempting to find proteins involved in the pain process and correlating with pain but not degree of inflammation in children with juvenile idiopathic arthritis (JIA), using a proteomics panel. METHODS: A total of 87 plasma samples were collected from 51 children with JIA (51 at diagnosis in a higher disease activity state, 18 at follow-up in a lower disease activity state) and 18 healthy controls. Relative levels of 92 proteins related to a wide range of biological processes in inflammation were obtained using a proximity extension assay panel. Comparisons between children with and without JIA, in different disease categories, by juvenile disease activity score (JADAS27) and degree of pain on a visual analogue scale (VAS), were performed using parametric and non-parametric statistical methods. RESULTS: Nineteen proteins involved in arthritic inflammation, such as interleukin 6 (IL-6) and S100 protein A12, were higher in patients with JIA than controls, seven decreased significantly during treatment, and 18 correlated significantly with JADAS27. Three proteins correlated with pain VAS scores in unadjusted analyses: the glial cell line-derived neurotrophic factor (GDNF), transforming growth factor beta, and IL-18R1. Levels of GDNF correlated significantly with pain VAS scores but not with JADAS27. CONCLUSIONS: Plasma levels of 18 of 92 tested proteins correlated with degree of disease activity. Levels of three proteins correlated with pain, and levels of one, GDNF, originating from neural cells, correlated with pain without correlating with inflammatory degree, suggesting that it may play a role in pain in JIA. Further studies in larger cohorts are warranted.

Gender differences in juvenile systemic sclerosis patients: Results from the international juvenile scleroderma inception cohort.

Objective: To compare organ involvement and disease severity between male and female patients with juvenile onset systemic sclerosis. Methods: Demographics, organ involvement, laboratory evaluation, patient-reported outcomes and physician assessment variables were compared between male and female juvenile onset systemic sclerosis patients enrolled in the prospective international juvenile systemic sclerosis cohort at their baseline visit and after 12 months. Results: One hundred and seventy-five juvenile onset systemic sclerosis patients were evaluated, 142 females and 33 males. Race, age of onset, disease duration, and disease subtypes (70% diffuse cutaneous) were similar between males and females. Active digital ulceration, very low body mass index, and tendon friction rubs were significantly more frequent in males. Physician global assessment of disease severity and digital ulcer activity was significantly higher in males. Composite pulmonary involvement was also more frequent in males, though not statistically significantly. After 12 months, they are the pattern of differences changed female patients had significantly more frequent pulmonary involvement. Conclusion: In this cohort, juvenile onset systemic sclerosis had a more severe course in males at baseline and but the pattern changed after 12 months. Some differences from adult findings persisted, there is no increased signal of pulmonary arterial hypertension or heart failure in male pediatric patients. While monitoring protocols of organ involvement in juvenile onset systemic sclerosis need to be identical for males and females.

Inflammatory Biomarkers Can Differentiate Acute Lymphoblastic Leukemia with Arthropathy from Juvenile Idiopathic Arthritis Better Than Standard Blood Tests.

OBJECTIVE: To evaluate the predictive value of biomarkers of inflammation like phagocyte-related S100 proteins and a panel of inflammatory cytokines in order to differentiate the child with acute lymphoblastic leukemia (ALL) from juvenile idiopathic arthritis (JIA). STUDY DESIGN: In this cross-sectional study, we measured S100A9, S100A12, and 14 cytokines in serum from children with ALL (n = 150, including 27 with arthropathy) and JIA (n = 236). We constructed predictive models computing areas under the curve (AUC) as well as predicted probabilities in order to differentiate ALL from JIA. Logistic regression was used for predictions of ALL risk, considering the markers as the respective exposures. We performed internal validation using repeated 10-fold cross-validation and recalibration, adjusted for age. RESULTS: In ALL, the levels of S100A9, S100A12, interleukin (IL)-1 beta, IL-4, IL-13, IL-17, matrix metalloproteinase-3, and myeloperoxidase were low compared with JIA (P < .001). IL-13 had an AUC of 100% (95% CI 100%-100%) due to no overlap between the serum levels in the 2 groups. Further, IL-4 and S100A9 had high predictive performance with AUCs of 99% (95% CI 97%-100%) and 98% (95% CI 94%-99%), respectively, exceeding both hemoglobin, platelets, C-reactive protein, and erythrocyte sedimentation rate. CONCLUSIONS: The biomarkers S100A9, IL-4, and IL-13 might be valuable markers to differentiate ALL from JIA.

Severe Raynaud's phenomenon from ethosuximide raised concern over possible onset of systemic vasculitis: a case report.

BACKGROUND: Ethosuximide and other anti-epileptic drugs have been reported to cause idiosyncratic reactions such as lupus-like syndromes, with elevated antinuclear antibody (ANA) levels. Herein, we present a case of a girl who developed a very severe Raynaud's phenomenon reaction and anti-Scl-70 antibodies related to treatment with ethosuximide, due to juvenile absence epilepsy (JAE). CASE PRESENTATION: A 12-year-old girl was diagnosed with JAE and treatment with ethosuximide was initiated. Two and a half months later her fingers, digits II-V bilaterally, began to ache and were discolored, alternatingly white, blue, or normal-colored. Two weeks later, her fingers were bluish-black, aching severely, almost continuously. The family sought medical advice. Ethosuximide was halted and due to the severe symptoms, treatment with both prednisolone and intravenous iloprost was commenced. Laboratory tests revealed high ANA levels with anti-Scl-70 pattern and confirmed anti-Scl-70 antibodies. After a few weeks, she started to improve and the symptoms slowly decreased over five months. Anti-Scl-70 was still detectable four months after onset of symptoms, though she was much improved. After eleven months, repeated ANA analyses were completely negative. CONCLUSION: Although extremely rare, it is important to recognize that severe Raynaud's phenomenon, threatening peripheral digital circulation, may occur as an idiosyncratic reaction to ethosuximide, raising concern over possible onset of vasculitis.

Haptoglobin in Juvenile Idiopathic Arthritis.

BACKGROUND: Haptoglobin (Hp), a liver derived acute phase inflammatory protein (APP), has scarcely been studied in juvenile idiopathic arthritis (JIA). Hp can occur in blood as two isoforms (Hp1 and Hp2) in precursor and mature forms. Routine clinical chemistry immunoturbidimetry does not discern these forms. It is unknown how different forms relate to disease activity in JIA. Our aims were to determine allele frequency and plasma concentrations of different Hp forms at higher versus lower JIA disease activity and compare to other APPs. METHODS: Plasma from JIA (n = 77) and healthy (n = 42) children were analyzed for apparent Hp allelic frequency and densitometric concentrations of alpha forms by Western blot (WB). Polymerase chain reaction (PCR) (buffy coat) was performed in a subset to estimate conformity with genetics. At higher versus lower juvenile arthritis disease activity score (JADAS27) (which includes erythrocyte sedimentation rate (ESR)), total mature Hp concentration from WB was compared and correlated against immunoturbidimetry and total protein, albumin, serum amyloid A (SAA) and C-reactive protein (CRP). RESULTS: At 300-fold dilution needed to study mature forms in Western blot, precursors were undetectable. Hp2 contributed most signal in most samples. Hp allele frequency was similar in JIA and controls. Both mature forms, taken separately or by sum, declined following treatment, but remained above concentrations of healthy controls, even in a remission subset that achieved JADAS27 < 1. Densitometry correlated with immunoturbidimetry. Hp concentrations correlated with JADAS27, albumin (negatively), CRP and SAA with immunoturbidimetric method correlating strongest to JADAS27 (Spearman R ~ 0.6, p < 0.0001). CONCLUSION: Hp allele frequency in JIA is similar to the general population, indicating that children with JIA should have the same possibility as in healthy children to produce preHp2 (zonulin), thought to increase intestinal permeability. Circulating Hp concentrations largely parallel other APPs and ESR; none of these measures correlate very strongly to JADAS27 score but Hp can be measured from capillary sampling which is impossible with ESR.

Transitioning patients with juvenile idiopathic arthritis to adult care: the Nordic experience.

BACKGROUND: With juvenile idiopathic arthritis (JIA), there are several protocols and practices used worldwide for the transition from paediatric to adult care. In this study, we examined the transferral rates and disease activity after transition, as well as the disease- and health-related outcomes. We also introduce the transition practices employed in the Nordic countries. METHODS: The study population comprised 408 participants with a disease onset from 1997 to 2000 who attended an 18-year follow-up visit in this population-based Nordic JIA cohort study. The patients were retrospectively divided into three subgroups: Patients transferred directly from paediatric care to adult rheumatology care, patients referred there later, and patients never transferred during the 18-year follow-up period. RESULTS: One hundred and sixty-three (40%) JIA patients had been directly transferred to an adult clinic. The cumulative transition rate was 52%, but there were significant differences between the participating centres. Fifty patients had later been referred to an adult clinic. Among the 195 patients who had never been transferred, 39% were found to have disease activity at the study visit. CONCLUSION: This study highlights the need to reconsider transition practices to avoid our undesirable finding of patients with disease activity in JIA, but no appropriate health care follow-up.

A Pilot Study Investigating Faecal Microbiota After Two Dietary Interventions in Children with Juvenile Idiopathic Arthritis.

There is evidence for an impact of the gut microbiota on the immune system, which has consequences for inflammatory diseases. Exclusive enteral nutrition (EEN) and the specific carbohydrate diet (SCD) have been demonstrated as effective anti-inflammatory treatments for children with Crohn's disease. We have previously shown an anti-inflammatory effect from these nutritional treatments in children with juvenile idiopathic arthritis (JIA). The aim of this study was to investigate if improved clinical symptoms after EEN or SCD treatment in children with JIA could be linked to changes in faecal microbiota. We included sixteen patients with JIA (age 7-17 years), six for treatment with EEN and ten with SCD. EEN was given for 3-5 weeks and SCD for 4-5 weeks, with clinical and laboratory status assessed before and after treatment. Faecal samples were analysed for microbiota diversity and composition using 16S rRNA gene sequencing. Analyses of the faecal microbiota showed an effect on the overall composition with both interventions; the most striking result was a decreased relative abundance of the genus Faecalibacterium from EEN and of Bifidobacterium from SCD. The α-diversity decreased significantly from SCD (P = 0.04), but not from EEN (P = 0.22). Despite the study cohorts being small, both EEN and SCD were shown to impact the faecal microbiota. Future larger studies with a focus on metagenomics or metabolomics could possibly reveal a link and clarify the clinical effects of those nutritional regimens.

Changing Patterns in Treatment, Remission Status, and Categories in a Long-Term Nordic Cohort Study of Juvenile Idiopathic Arthritis.

OBJECTIVE: To explore sustainability of achieved remission off medication and defined International League of Associations for Rheumatology (ILAR) categories in juvenile idiopathic arthritis (JIA) and describe the trajectory of disease course over time by comparing treatment, disease activity, and ILAR categories from baseline, 8 years, and 18 years after disease onset. METHODS: A total of 373 of the 510 included patients were initially recruited consecutive cases of JIA from the prospective, longitudinal, population-based Nordic JIA cohort with disease onset during 1997-2000 from Denmark, Norway, Sweden, and Finland in an 18-year follow-up study. Clinical data were collected consecutively at baseline, 8 years, and 18 years after disease onset and were evaluated regarding treatment, disease activity, and ILAR category. RESULTS: Significantly more patients (70%) were off medication after 18 years of follow-up compared to after 8 years (59.7%); nevertheless, the number of patients in remission had not increased (52% off medication versus 51% on medication). Twelve percent of patients changed ILAR category between 8 years and 18 years after disease onset. Almost half of the changes were due to updated information about heredity in a first-degree relative. In the same period, the psoriatic arthritis group increased significantly in number (P < 0.001), in contrast to the oligoarticular category, which decreased (P = 0.02). The undifferentiated group increased 24% from 8 to 18 years of follow-up; however, this increase was not significant (P = 0.06). CONCLUSION: In this Nordic JIA cohort study, the remission rate did not increase even though significantly more patients were off medication at the 18-year follow-up compared to at the 8-year follow-up after disease onset. The distribution of patients in the ILAR categories continued to change significantly throughout the 18-year study period.

Population-based study of multisystem inflammatory syndrome associated with COVID-19 found that 36% of children had persistent symptoms.

AIM: Our aim was to describe the outcomes of multisystem inflammatory syndrome in children (MIS-C) associated with COVID-19. METHODS: This national, population-based, longitudinal, multicentre study used Swedish data that were prospectively collected between 1 December 2020 and 31 May 2021. All patients met the World Health Organization criteria for MIS-C. The outcomes 2 and 8 weeks after diagnosis are presented, and follow-up protocols are suggested. RESULTS: We identified 152 cases, and 133 (87%) participated. When followed up 2 weeks after MIS-C was diagnosed, 43% of the 119 patients had abnormal results, including complete blood cell counts, platelet counts, albumin levels, electrocardiograms and echocardiograms. After 8 weeks, 36% of 89 had an abnormal patient history, but clinical findings were uncommon. Echocardiogram results were abnormal in 5% of 67, and the most common complaint was fatigue. Older children and those who received intensive care were more likely to report symptoms and have abnormal cardiac results. CONCLUSION: More than a third (36%) of the patients had persistent symptoms 8 weeks after MIS-C, and 5% had abnormal echocardiograms. Older age and higher levels of initial care appeared to be risk factors. Structured follow-up visits are important after MIS-C.

M-ficolin: a valuable biomarker to identify leukaemia from juvenile idiopathic arthritis.

OBJECTIVE: Distinction on clinical grounds between acute lymphoblastic leukaemia presenting with arthropathy (ALLarthropathy) and juvenile idiopathic arthritis (JIA) is difficult, as the clinical and paraclinical signs of leukaemia may be vague. The primary aim was to examine the use of lectin complement pathway proteins as markers to differentiate ALLarthropathy from JIA. The secondary aims were to compare the protein levels at baseline and follow-up in a paired number of children with ALL and to examine the correlation with haematology counts, erythrocyte sedimentation reaction (ESR), C-reactive protein (CRP), blasts, relapse and death. STUDY DESIGN: In this observational study, we measured M-ficolin, CL-K1 and MASP-3 in serum from children with ALL (n=151) and JIA (n=238) by time-resolved immunofluorometric assays. Logistic regression was used for predictions of ALL risk, considering the markers as the respective exposures. We performed internal validation using repeated '10-fold cross-validation' with 100 repetitions computing the area under the curve (AUC) as well as positive and negative predictive values in order to evaluate the predictive performance. RESULTS: The level of M-ficolin was higher in JIA than ALLtotal and the ALLarthropathy subgroup. The M-ficolin level normalised after remission of ALL. M-ficolin could differentiate ALL from JIA with an AUC of 94% and positive predictive value (PPV) of 95%, exceeding CRP and haemoglobin. In a dichotomised predictive model with optimal cut-offs for M-ficolin, platelets and haemoglobin, AUC was 99% and PPV 98% in detecting ALL from JIA. CONCLUSION: M-ficolin is a valuable marker to differentiate the child with ALL from JIA.

Differences Sustained Between Diffuse and Limited Forms of Juvenile Systemic Sclerosis in an Expanded International Cohort.

OBJECTIVE: To evaluate the baseline clinical characteristics of juvenile systemic sclerosis (SSc) patients in the international juvenile SSc inception cohort, and to compare these characteristics between the classically defined juvenile diffuse cutaneous SSc (dcSSc) and limited cutaneous SSc (lcSSc) subtypes and among those with overlap features. METHODS: A cross-sectional study was performed using baseline visit data. Information on demographic characteristics, organ system evaluation, treatment, and patient- and physician-reported outcomes was extracted and summary statistics applied. Comparisons between juvenile dcSSc and lcSSc subtypes and patients with and without overlap features were performed using chi-square and Mann-Whitney U tests. RESULTS: At data extraction, 150 juvenile SSc patients were enrolled across 42 centers; 83% were White, 80% were female, juvenile dcSSc predominated (72%), and 17% of the cohort had overlap features. Significant differences were found between juvenile dcSSc and juvenile lcSSc regarding modified Rodnan skin thickness score, the presence of Gottron's papules, digital tip ulceration, results of the 6-minute walk test, and composite pulmonary and cardiac involvement. All of these were more frequent in dcSSc except for cardiac involvement. Juvenile dcSSc patients had significantly worse scores for physician-rated disease activity and damage. A significantly higher occurrence of Gottron's papules and musculoskeletal and composite pulmonary involvement, and a significantly lower frequency of Raynaud's phenomenon, were seen in those with overlap features. CONCLUSION: Results from a large international juvenile SSc cohort demonstrate significant differences between juvenile dcSSc and juvenile lcSSc patients, including more globally severe disease and increased frequency of interstitial lung disease in juvenile dcSSc patients, while those with lcSSc have more frequent cardiac involvement. Those with overlap features had an unexpected higher frequency of interstitial lung disease.

Underdetection of Interstitial Lung Disease in Juvenile Systemic Sclerosis.

OBJECTIVE: Utilizing data obtained from a prospective, international, juvenile systemic sclerosis (SSc) cohort, the present study was undertaken to determine if pulmonary screening with forced vital capacity (FVC) and diffusing capacity for carbon monoxide (DLco) is sufficient to assess the presence of interstitial lung disease (ILD) in comparison to high-resolution computed tomography (HRCT) in juvenile SSc. METHODS: The juvenile SSc cohort database was queried for patients enrolled from January 2008 to January 2020 with recorded pulmonary function tests (PFTs) parameters and HRCT to determine the discriminatory properties of PFT parameters, FVC, and DLco in detecting ILD. RESULTS: Eighty-six juvenile SSc patients had both computed tomography imaging and FVC values for direct comparison. Using findings on HRCT as the standard measure of ILD presence, the sensitivity of FVC in detecting ILD in juvenile SSc was only 40%, the specificity was 77%, and area under the curve (AUC) was 0.58. Fifty-eight juvenile SSc patients had both CT imaging and DLco values for comparison. The sensitivity of DLco in detecting ILD was 76%, the specificity was 70%, and AUC was 0.73. CONCLUSION: The performance of PFTs in juvenile SSc to detect underlying ILD was quite limited. Specifically, the FVC, which is one of the main clinical parameters in adult SSc to detect and monitor ILD, would miss ~60% of children who had ILD changes on their accompanying HRCT. The DLco was more sensitive in detecting potential abnormalities on HRCT, but with less specificity than the FVC. These results support the use of HRCT in tandem with PFTs for the screening of ILD in juvenile SSc.

A cross-sectional cohort study of the activity and turnover of neutrophil granulocytes in juvenile idiopathic arthritis.

BACKGROUND: The inflammatory process in juvenile idiopathic arthritis (JIA) involves both the innate and the adaptive immune system. The turnover and activity of neutrophil granulocytes may be reflected by proteins secreted from primary or secondary granules and from the cytoplasm of sequestered cells. Our primary aim was to compare the levels of the secondary neutrophil granule protein human neutrophil lipocalin (HNL), in JIA patients and controls, and to explore a possible priming of neutrophils through parallel analyses in plasma and serum. A secondary aim was to relate the levels of HNL to two other well-studied leukocyte proteins, S100A8/A9 and myeloperoxidase (MPO), as well as to clinical aspects of JIA. METHODS: The concentrations of the three biomarkers in serum, two of them also in plasma, were measured using enzyme-linked immunosorbent assay in 37 children with JIA without medical treatment, in high disease activity based on juvenile arthritis disease activity score 27 (JADAS27), 32 children on medical treatment, mainly in lower disease activity, and 16 healthy children. We assessed for differences between two groups using the Mann-Whitney U test, and used the Kruskal-Wallis test for multiple group comparisons. Spearman rank correlation, linear and multiple regression analyses were used for evaluation of associations between biomarker concentrations and clinical scores. RESULTS: The concentrations of HNL and MPO in serum were significantly increased in children with JIA (p < 0.001, p = 0.002) compared with healthy children, but we found no difference in the plasma levels of HNL and MPO between children with JIA and controls. The serum concentrations of MPO and HNL were unaffected by medical treatment, but S100A8/A9 was reduced by medical treatment and correlated with JADAS27 in both univariate (r = 0.58, p < 0.001) and multivariate (r = 0.59, p < 0.001) analyses. CONCLUSIONS: Neutrophil granulocytes in children with JIA are primed to release primary and secondary granule proteins, without relation to medical treatment, whereas signs of increased turnover and sequestration of neutrophil granulocytes are reduced by treatment. Levels of neutrophil-originating proteins in serum most likely reflect underlying disease activities of JIA.

A pilot study of possible anti-inflammatory effects of the specific carbohydrate diet in children with juvenile idiopathic arthritis.

BACKGROUND: To explore possible anti-inflammatory effects of the specific carbohydrate diet in children with juvenile idiopathic arthritis. This diet has shown anti-inflammatory effect in children with inflammatory bowel disease. METHODS: Twenty-two patients with juvenile idiopathic arthritis (age 6.3-17.3 years), with ≤2 inflamed joints and an erythrocyte sedimentation rate < 30 mm/h, were included in this explorative study. Fifteen children completing four weeks on the diet were evaluated. A dietician introduced parents and children to the diet, and two follow-ups were performed during the intervention. Conventional laboratory tests and multiplex analyses of 92 inflammatory proteins were used. Short-chain fatty acids in faecal samples were examined. RESULTS: The diet significantly decreased morning stiffness (p = 0.003) and pain (p = 0.048). Physical function, assessed through the child health assessment questionnaire, improved (p = 0.022). Arthritis improved in five of the seven children with arthritis; in those seven, multiplex analyses showed a significant decrease in nine inflammatory proteins, including TNF-alpha (p = 0.028), after four weeks. Faecal butyrate, analysed in all 15 participants, increased significantly (p = 0.020). CONCLUSION: The specific carbohydrate diet may have significant positive effects on arthritis in children with juvenile idiopathic arthritis, but further studies are needed. CLINICAL TRIALS IDENTIFIER: NCT04205500 , 2019/12/17, retrospectively registered. URL: https://register.clinicaltrials.gov.