Clinical Characteristics of Adolescents With Juvenile Idiopathic Arthritis Transitioning to Adult Rheumatology Care in Canada: Results From the CAPRI Registry.

OBJECTIVE: Using Canadian Alliance of Pediatric Rheumatology Investigators (CAPRI) juvenile idiopathic arthritis (JIA) registry data, we describe (1) clinical characteristics of patients with JIA transitioning to adult care, (2) prevalence of disease-related damage and complications, and (3) changes in disease activity during the final year prior to transfer. METHODS: Registry participants who turned 17 years between February 2017 and November 2021 were included. Clinical characteristics and patient-reported outcomes (PROs) at the last recorded pediatric rheumatology visit, and changes observed in the year prior to that visit were analyzed. Physicians completed an additional questionnaire characterizing cumulative disease-related damage and adverse events by age 17 years. RESULTS: At their last visit, 88 of 131 participants (67%) had inactive and 42 (32%) had active disease. Overall, 96 (73%) were on medications and 41 (31%) were on biologic disease-modifying antirheumatic drugs. Among 80 participants for whom the additional questionnaire was completed, 26% had clinically detected joint damage, 31% had joint damage on imaging, 14% had uveitis, and 7.5% had experienced at least 1 serious adverse event. During the final year, 44.2% of patients were in remission, 28.4% attained inactive disease, and 27.4% became or remained active. Mean scores of PROs were stable overall during that last year, but a minority reported marked worsening. CONCLUSION: A substantial proportion of youth with JIA transitioning to adult care in Canada had a high disease burden, which was reflected by their degree of disease activity, joint damage, or ongoing medication use. These results will inform pediatric and adult providers of anticipated needs during transition of care.

Comparing Canadian paediatric rheumatology practice to the 2019 ACR Juvenile Idiopathic Arthritis guidelines: results from the CAPRI Registry.

OBJECTIVE: To identify differences between baseline Canadian JIA practices and the 2019 ACR guidelines for JIA. METHODS: Canadian paediatric rheumatologists were surveyed for their opinions on reasonable a priori target adherence rates for JIA guideline recommendations. Prospectively collected data for 266 newly diagnosed children from 2017 to 2019 were analysed to calculate observed adherence rates. Kaplan-Meier survival curves were used to estimate the cumulative incidence of starting synthetic or biologic DMARDs (sDMARD or bDMARD, respectively) for different patient groups. RESULTS: A total of 25/61 (41%) eligible physicians answered the survey. Most survey respondents (64%) felt that adherence targets should vary depending on the strength of the recommendation and quality of evidence, from a mean of 84% for strong recommendations with high-quality evidence to 29% for conditional recommendations with very low-quality evidence. Data showed 13/19 (68%) recommendations would have met proposed targets and 10/19 (53%) had ≥80% observed adherence. Exceptions were the use of subcutaneous vs oral MTX (53%) and infrequent treatment escalation from NSAIDs to bDMARDs in patients with sacroiliitis (31%) or enthesitis (0%). By 12 weeks, 95% of patients with polyarthritis received sDMARDs, 38% of patients with systemic JIA received bDMARDs and 22% of patients with sacroiliitis received bDMARDs. CONCLUSION: Canadian paediatric rheumatology practices were in line with many 2019 JIA guideline recommendations before their publication, except for frequent use of oral MTX and infrequent direct escalation from NSAIDs to bDMARDs in sacroiliitis and enthesitis.

Comprehensive and reliable sonographic assessment and scoring system for inflammatory lesions of the paediatric ankle.

OBJECTIVE: The clinical decision-making process in paediatric arthritis lacks an objective, reliable bedside imaging tool. The aim of this study was to develop a US scanning protocol and assess the reliability of B-mode and Doppler scoring systems for inflammatory lesions of the paediatric ankle. METHODS: As part of the Childhood Arthritis and Rheumatology Research Alliance (CARRA) US group, 19 paediatric rheumatologists through a comprehensive literature review developed a set of standardized views and scoring systems to assess inflammatory lesions of the synovial recesses as well as tendons of the paediatric ankle. Three rounds of scoring of still images were followed by one practical exercise. Agreement among raters was assessed using two-way single score intraclass correlation coefficients (ICC). RESULTS: Of the 37 initially identified views to assess the presence of ankle synovitis and tenosynovitis, nine views were chosen for each B-mode and Doppler mode semi-quantitative evaluation. Several scoring exercises and iterative modifications resulted in a final highly reliable scoring system: anterior tibiotalar joint ICC: 0.93 (95% CI 0.92, 0.94), talonavicular joint ICC: 0.86 (95% CI 0.81, 0.90), subtalar joint ICC: 0.91 (95% CI 0.88, 0.93) and tendons ICC: 0.96 (95% CI 0.95, 0.97). CONCLUSION: A comprehensive and reliable paediatric ankle US scanning protocol and scoring system for the assessment of synovitis and tenosynovitis were successfully developed. Further validation of this scoring system may allow its use as an outcome measure for both clinical and research applications.

Reliability of the Pediatric Specific Musculoskeletal Ultrasound Scoring Systems for the Elbow, Wrist, and Finger Joints.

OBJECTIVE: Musculoskeletal ultrasound (MSUS) is increasingly being used in the evaluation of pediatric musculoskeletal diseases. In order to provide objective assessments of arthritis, reliable MSUS scoring systems are needed. Recently, joint-specific scoring systems for arthritis of the pediatric elbow, wrist, and finger joints were proposed by the Childhood Arthritis and Rheumatology Research Alliance (CARRA) MSUS workgroup. This study aimed to assess the reliability of these scoring systems when used by sonographers with different levels of expertise. METHODS: Members of the CARRA MSUS workgroup attended training sessions for scoring the elbow, wrist, and finger. Subsequently, scoring exercises of B mode and power Doppler (PD) mode still images for each joint were performed. Interreader reliability was determined using 2-way single-score intraclass correlation coefficients (ICCs) for synovitis and Cohen [Formula: see text] for tenosynovitis. RESULTS: Seventeen pediatric rheumatologists with different levels of MSUS expertise (1-15 yrs) completed a 2-hour training session and calibration exercise for each joint. Excellent reliability (ICC > 0.75) was found after the first scoring exercise for all the finger and elbow views evaluated on B mode and PD mode, and for all of the wrist views on B mode. After a second training session and a scoring exercise, the wrist PD mode views reached excellent reliability as well. CONCLUSION: The preliminary CARRA MSUS scoring systems for assessing arthritis of the pediatric elbow, wrist, and finger joints demonstrate excellent reliability among pediatric MSUS sonographers with different levels of expertise. With further validation, this reliable joint-specific scoring system could serve as a clinical tool and scientific outcome measure.

Paediatric inflammatory multisystem syndrome in Canada: population-based surveillance and role of SARS-CoV-2 linkage.

BACKGROUND: Paediatric inflammatory multisystem syndrome (PIMS) is a rare condition temporally associated with SARS-CoV-2 infection. Using national surveillance data, we compare presenting features and outcomes among children hospitalized with PIMS by SARS-CoV-2 linkage, and identify risk factors for intensive care (ICU). METHODS: Cases were reported to the Canadian Paediatric Surveillance Program by a network of >2800 pediatricians between March 2020 and May 2021. Patients with positive versus negative SARS-CoV-2 linkages were compared, with positive linkage defined as any positive molecular or serologic test or close contact with confirmed COVID-19. ICU risk factors were identified with multivariable modified Poisson regression. RESULTS: We identified 406 children hospitalized with PIMS, including 49.8% with positive SARS-CoV-2 linkages, 26.1% with negative linkages, and 24.1% with unknown linkages. The median age was 5.4 years (IQR 2.5-9.8), 60% were male, and 83% had no comorbidities. Compared to cases with negative linkages, children with positive linkages experienced more cardiac involvement (58.8% vs. 37.4%; p < 0.001), gastrointestinal symptoms (88.6% vs. 63.2%; p < 0.001), and shock (60.9% vs. 16.0%; p < 0.001). Children aged ≥6 years and those with positive linkages were more likely to require ICU. CONCLUSIONS: Although rare, 30% of PIMS hospitalizations required ICU or respiratory/hemodynamic support, particularly those with positive SARS-CoV-2 linkages. IMPACT: We describe 406 children hospitalized with paediatric inflammatory multisystem syndrome (PIMS) using nationwide surveillance data, the largest study of PIMS in Canada to date. Our surveillance case definition of PIMS did not require a history of SARS-CoV-2 exposure, and we therefore describe associations of SARS-CoV-2 linkages on clinical features and outcomes of children with PIMS. Children with positive SARS-CoV-2 linkages were older, had more gastrointestinal and cardiac involvement, and hyperinflammatory laboratory picture. Although PIMS is rare, one-third required admission to intensive care, with the greatest risk amongst those aged ≥6 years and those with a SARS-CoV-2 linkage.

Development and validation of the Kids Disability Screen for children with juvenile idiopathic arthritis: results from the CAPRI Registry.

OBJECTIVE: The aim of this study was to develop and validate a brief disability screen for children with JIA, the Kids Disability Screen (KDS). METHODS: A total of 216 children enrolled in the Canadian Alliance of Pediatric Rheumatology Investigators (CAPRI) Registry in 2017-2018 formed a development cohort, and 220 children enrolled in 2019-2020 formed a validation cohort. At every clinic visit, parents answered two questions derived from the Childhood Health Assessment Questionnaire (CHAQ): 'Is it hard for your child to run and play BECAUSE OF ARTHRITIS?' ('Hard' 0-10), and 'Does your child usually need help from you or another person BECAUSE OF ARTHRITIS?' ('Help', 0-10). We used 36-fold cross-validation and tested nine different mathematical methods to combine the answers and optimize psychometric properties. The results were confirmed in the validation cohort. RESULTS: Expressed as the mean of the two answers, KDS best balanced ease of use and psychometric properties, while a LASSO regression model combining the two answers with other patient characteristics [estimated CHAQ [eCHAQ]) had the highest responsiveness. In the validation cohort, 22.7%, 25.9% and 28.6% of patients had a score of 0 at enrolment for the KDS, eCHAQ and CHAQ, respectively. Responsiveness was 0.67, 0.74 and 0.62, respectively. Sensitivity to detect a CHAQ > 0 was 0.90 and specificity 0.56, KDS detecting some disability in 44% of children with a CHAQ = 0. CONCLUSION: This simple KDS has psychometric properties comparable with those of a full CHAQ and may be used at every clinic visit to identify those children who need a full disability assessment.

Impact of the COVID-19 pandemic on juvenile idiopathic arthritis presentation and research recruitment: results from the CAPRI registry.

OBJECTIVE: The COVID-19 pandemic has disrupted healthcare delivery and clinical research worldwide, with data from areas most affected demonstrating an impact on rheumatology care. This study aimed to characterize the impact of the pandemic on the initial presentation of JIA and JIA-related research in Canada. METHODS: Data collected from the Canadian Alliance of Pediatric Rheumatology Investigators JIA Registry from the year pre-pandemic (11 March 2019 to 10 March 2020) was compared with data collected during the first year of the pandemic (11 March 2020 to 10 March 2021). Outcomes included time from symptom onset to first assessment, disease severity at presentation and registry recruitment. Proportions and medians were used to describe categorical and continuous variables, respectively. RESULTS: The median time from symptom onset to first assessment was 138 (IQR 64-365) days pre-pandemic vs 146 (IQR 83-359) days during the pandemic. The JIA category frequencies remained overall stable (44% oligoarticular JIA pre-pandemic, 46.8% pandemic), except for systemic JIA (12 cases pre-pandemic, 1 pandemic). Clinical features, disease activity (cJADAS10), disability (CHAQ) and quality of life (JAQQ) scores were similar between the two cohorts. Pre-pandemic, 225 patients were enrolled, compared with 111 in the pandemic year, with the greatest decrease from March to June 2020. CONCLUSIONS: We did not observe the anticipated delay in time to presentation or increased severity at presentation, suggesting that, within Canada, care adapted well to provide support to new patient consults without negative impacts. The COVID-19 pandemic was associated with an initial 50% decrease in registry enrolment but has since improved.

Recent developments in lanthanide-doped mid-infrared fluoride fiber lasers [Invited].

Mid-infrared fiber sources, emitting between 2.5 µm and 5.0 µm, are interesting for their great potential in several application fields such as material processing, biomedicine, remote sensing and infrared countermeasures due to their high-power, their diffraction-limited beam quality as well as their robust monolithic architecture. In this review, we will focus on the recent progress in continuous wave and pulsed mid-infrared fiber lasers and the components that bring these laser sources closer to a field deployment as well as in industrial systems. Accordingly, we will briefly illustrate the potential of such mid-infrared fiber lasers through a few selected applications.

A new Canadian inception cohort for juvenile idiopathic arthritis: The Canadian Alliance of Pediatric Rheumatology Investigators Registry.

OBJECTIVES: The aim was to describe the design, methods and initial findings of a new Canadian inception cohort of children with JIA, The Canadian Alliance of Pediatric Rheumatology Investigators (CAPRI) JIA Registry. METHODS: The CAPRI JIA Registry was started in 2017 to collect information prospectively on children enrolled within 3 months of JIA diagnosis across Canada. The registry has a non-traditional modular design, with no artificially set times for registry visits to occur, streamlined multi-method data collection that requires 2-4 min per visit, and reports cumulative incidence of treatments, outcomes and adverse events calculated by Kaplan-Meier survival methods. RESULTS: A total of 166 patients, enrolled a median of 6 weeks after JIA diagnosis at 10 centres, were included. The median age at diagnosis was 9 years [interquartile range (IQR) 3, 13], 61% were female and 51% had oligoarticular JIA. The median three-variable clinical Juvenile Arthritis Disease Activity Score was 6.5 (IQR 4, 10) at enrolment, and the median time to first attainment of clinically inactive disease (CID) was 24 weeks (by 1 year, 81%). Within 1 year of diagnosis, 70% of patients had started a DMARD and 35% a biologic agent. The rates of adverse events and serious adverse events were 60 and 5.8 per 100 patient-years, respectively. CONCLUSION: This streamlined and flexible registry minimizes the burden of data collection and interference with clinic operations. Initial findings suggest that treatments for newly diagnosed patients with JIA in Canada have intensified, and now 81% of patients attain CID within 1 year of diagnosis.

Long period fiber gratings for the mitigation of parasitic laser effects in mid-infrared fiber amplifiers.

A concept to mitigate parasitic lasing in mid-IR fiber amplifiers using a single long period fiber grating is shown. Using tightly confined ultrashort laser pulses at 800 nm, a grating was directly inscribed into the core of an erbium doped fluoride glass fiber showing a strong attenuation down to -27 dB at desired wavelength. The concept reveals great potential to improve the average output power and attainable spectral range of low repetition rate in-amplifier supercontinuum generation.

20 W splice-free erbium-doped all-fiber laser operating at 1610 nm.

We report on a splice-free erbium-doped all-fiber laser emitting over 20 W at a wavelength of 1610 nm, with a slope efficiency of 19.6 % and an overall efficiency of 18.3% with respect to the launched pump power at 976 nm. The simple cavity design takes advantage of fiber Bragg gratings written directly in the gain fiber through the polymer coating and clad-pumping from a single commercial pump diode to largely simplify the assembling process, making this cavity ideal for large-scale commercial deployment. Two single-mode and singly erbium-doped silica fibers were fabricated in-house: the first to assess the effects of a high erbium concentration (0.36 mol.% Er2O3), yielding a low efficiency of 2.5 % with respect to launched pump power, and the second to achieve the improved result mentioned above (0.03 mol.% Er2O3). Numerical simulations show the link between the performance of each cavity and ion pair-induced quenching.

Genetic control of contagious asexuality in the pea aphid.

Although evolutionary transitions from sexual to asexual reproduction are frequent in eukaryotes, the genetic bases of such shifts toward asexuality remain largely unknown. We addressed this issue in an aphid species where both sexual and obligate asexual lineages coexist in natural populations. These sexual and asexual lineages may occasionally interbreed because some asexual lineages maintain a residual production of males potentially able to mate with the females produced by sexual lineages. Hence, this species is an ideal model to study the genetic basis of the loss of sexual reproduction with quantitative genetic and population genomic approaches. Our analysis of the co-segregation of ∼ 300 molecular markers and reproductive phenotype in experimental crosses pinpointed an X-linked region controlling obligate asexuality, this state of character being recessive. A population genetic analysis (>400-marker genome scan) on wild sexual and asexual genotypes from geographically distant populations under divergent selection for reproductive strategies detected a strong signature of divergent selection in the genomic region identified by the experimental crosses. These population genetic data confirm the implication of the candidate region in the control of reproductive mode in wild populations originating from 700 km apart. Patterns of genetic differentiation along chromosomes suggest bidirectional gene flow between populations with distinct reproductive modes, supporting contagious asexuality as a prevailing route to permanent parthenogenesis in pea aphids. This genetic system provides new insights into the mechanisms of coexistence of sexual and asexual aphid lineages.

Mid-IR supercontinuum from 2.4 to 5.4 µm in a low-loss fluoroindate fiber.

A mid-infrared supercontinuum extending up to 5.4 µm is generated in a low-loss fluoroindate fiber. It is pumped with an erbium-doped fluoride fiber amplifier seeded with 400 ps pulses at 2.75 µm. Both fibers are fusion spliced to increase the robustness and long-term stability of the system. With more than 82% of the total power beyond 3 µm, this approach is promising for efficient mid-IR light generation.

Watt-level fiber-based femtosecond laser source tunable from 2.8 to 3.6 µm.

The development of compact and reliable ultrafast sources operating in the mid-infrared region could lead to major advances in both fundamental and applied sciences. In this Letter, we report on a simple and efficient laser system based entirely on erbium-doped fluoride glass fibers that generates high-energy Raman soliton pulses tunable from 2.8 to 3.6 µm at a high average output power. Stable 160 fs pulses at 3.4 µm with a maximum energy of 37 nJ, a corresponding average output power above 2 W, and an estimated peak power above 200 kW are demonstrated. This tunable source promises direct applications in laser processing of polymers and biological materials.

Compact 3-8 µm supercontinuum generation in a low-loss As2Se3 step-index fiber.

A mid-infrared supercontinuum source spanning from 3 to 8 µm is demonstrated using a low-loss As2Se3 commercial step-index fiber. A maximum average output power of 1.5 mW is obtained at a low repetition rate of 2 kHz. Thanks to the low NA step-index fiber, the output is single mode for wavelengths above ∼5 µm. The pump source consists of an erbium-doped ZrF4-based in-amplifier supercontinuum source spanning from 3 to 4.2 µm. The effects of both the pump power and As2Se3 fiber length on the output characteristics are studied. To the best of our knowledge, this is the first compact supercontinuum source ever reported to reach 8 µm in a standard step-index fiber.

In-amplifier mid-infrared supercontinuum generation.

Mid-infrared supercontinuum (SC) generation from 2.6 to 4.1 µm is demonstrated in a single-mode erbium-doped fluoride glass fiber amplifier pumped at 976 nm and seeded by an optical parametric generation (OPG) source emitting 400 ps pulses at 2.75 µm. Up to 82% of the SC power is generated beyond 3 µm. This novel and simple in-amplifier SC generation approach is promising for the development of compact and efficient sources operating in the mid-infrared, especially in the 3-5 µm band.

Relationship of Fatigue, Pain Interference, and Physical Disability in Children Newly Diagnosed With Juvenile Idiopathic Arthritis.

OBJECTIVE: Our objectives were to quantify the relationships among fatigue, pain interference, and physical disability in children with juvenile idiopathic arthritis (JIA) and to test whether fatigue mediates the relationship between pain interference and physical disability in JIA. METHODS: Patients enrolled within three months of JIA diagnosis in the Canadian Alliance of Pediatric Rheumatology Investigators (CAPRI) Registry between February 2017 and May 2023 were included. Their parents completed the Patient-Reported Outcomes Measurement Information System fatigue and pain interference short proxy questionnaires and the Childhood Health Assessment Questionnaire disability index at registry enrollment. Associations were assessed using Pearson correlations and multiple linear regression. Structural equation modeling (SEM) was used to test if fatigue mediates the relationship between pain interference and physical disability. RESULTS: Among 855 patients (61.4% female, 44.1% with oligoarthritis), most reported fatigue and pain interference scores similar to those in the reference population, but 15.6% reported severe fatigue and 7.3% reported severe pain interference, with wide variation across JIA categories. Fatigue was strongly correlated with pain interference (r = 0.72, P < 0.001) and with physical disability (r = 0.60, P < 0.001). Pain interference (ß = 0.027, P < 0.001) and fatigue (ß = 0.013, P < 0.001) were both associated with physical disability after controlling for each other and potential confounders. SEM supported our hypothesis that fatigue partially mediates the relationship between pain interference and physical disability. CONCLUSION: Our findings suggest both fatigue and pain interference are independently associated with physical disability in children newly diagnosed with JIA, and the effect of pain interference may be partly mediated by fatigue.

Resource use and disease severity of children hospitalized for COVID-19 versus multisystem inflammatory syndrome in children (MIS-C) in Canada.

Background: Direct comparisons of paediatric hospitalizations for acute coronavirus disease 2019 (COVID-19) and multisystem inflammatory syndrome in children (MIS-C) can inform health system planning. We describe the absolute and relative hospital burden of acute paediatric COVID-19 and MIS-C in Canada. Methods: This national prospective study was conducted via the Canadian Paediatric Surveillance Program from March 2020-May 2021. Children younger than 18 years old and hospitalized for acute COVID-19 or MIS-C were included in the analysis. Outcomes included supplemental oxygen (low-flow oxygen or high-flow nasal cannula), ventilation (non-invasive or conventional mechanical), vasopressors, paediatric intensive care unit (PICU) admission, or death. Adjusted risk differences (aRD) and 95% confidence intervals (CI) were calculated to identify factors associated with each diagnosis. Results: Overall, we identified 330 children hospitalized for acute COVID-19 (including five deaths) and 208 hospitalized for MIS-C (including zero deaths); PICU admission was required for 49.5% of MIS-C hospitalizations versus 18.2% of acute COVID-19 hospitalizations (aRD 20.3; 95% CI, 9.9-30.8). Resource use differed by age, with children younger than one year hospitalized more often for acute COVID-19 (aRD 43.4% versus MIS-C; 95% CI, 37.7-49.1) and more children 5-11 years hospitalized for MIS-C (aRD 38.9% vs. acute COVID-19; 95% CI, 31.0-46.9). Conclusion: While there were more hospitalizations and deaths from acute paediatric COVID-19, MIS-C cases were more severe, requiring more intensive care and vasopressor support. Our findings suggest that both acute COVID-19 and MIS-C should be considered when assessing the overall burden of severe acute respiratory syndrome coronavirus 2 in hospitalized children.

Evolutionary study of duplications of the miRNA machinery in aphids associated with striking rate acceleration and changes in expression profiles.

BACKGROUND: The sequencing of the genome of the pea aphid Acyrthosiphon pisum revealed an unusual expansion of the miRNA machinery, with two argonaute-1, two dicer-1 and four pasha gene copies. In this report, we have undertaken a deeper evolutionary analysis of the phylogenetic timing of these gene duplications and of the associated selective pressures by sequencing the two copies of ago-1 and dcr-1 in different aphid species of the subfamily Aphidinae. We have also carried out an analysis of the expression of both copies of ago-1 and dcr-1 by semi-quantitative PCR in different morphs of the pea aphid life cycle. RESULTS: The analysis has shown that the duplication of ago-1 occurred in an ancestor of the subfamily Aphidinae while the duplication of dcr-1 appears to be more recent. Besides, it has confirmed a pattern of one conserved copy and one accelerated copy for both genes, and has revealed the action of positive selection on several regions of the fast-evolving ago-1b. On the other hand, the semi-quantitative PCR experiments have revealed a differential expression of these genes between the morphs of the parthenogenetic and the sexual phases of Acyrthosiphon pisum. CONCLUSIONS: The discovery of these gene duplications in the miRNA machinery of aphids opens new perspectives of research about the regulation of gene expression in these insects. Accelerated evolution, positive selection and differential expression affecting some of the copies of these genes suggests the possibility of a neofunctionalization of these duplicates, which might play a role in the display of the striking phenotypic plasticity of aphids.