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Type d'Item : Item , Successful corticosteroid-free management of anti-HMG–CoA reductase immune-mediated necrotizing myopathy with subcutaneous immunoglobulins monotherapy: a case report(2026-06-16) Wilk, Nikola; Cowan, Juthaporn; Booth, Ronald A.; Warman-Chardon, Jodi; Maltez, Nancy; Ivory, CatherineAbstract Background Given the high rate of cardiovascular comorbidities in anti-HMG–CoA reductase (HMGCR)–immune-mediated necrotizing myopathy (IMNM), a glucocorticosteroids (GC)-free treatment approach remains an appealing strategy. While intravenous immunoglobulins (IVIg) represents an effective therapy in most subgroups of idiopathic inflammatory myositis (IIM), there remains limited evidence supporting the use subcutaneous immunoglobulins (SCIg), a potentially safer, more convenient and cost-effective alternative. Case presentation We present a case of a 68-year-old male of European descent with a 2-year history of progressive proximal bilateral lower extremity weakness. He had been treated for his dyslipidemia with atorvastatin for 2 years, then with rosuvastatin for 2 additional years until discontinued a year before our assessment. His other comorbidities included hypertension and diabetes mellitus type II. Physical examination demonstrated proximal weakness of his bilateral hip flexors and deltoids, and no rash. His creatine kinase (CK) was elevated at 1644 IU/L. Electromyography revealed a generalized myopathic disorder with proximal predominance and muscle biopsy of the right quadriceps showed typical findings of an IMNM. Serum HMG–CoA reductase antibody was positive. Due to accumulating evidence supporting the effectiveness of IVIg in anti-HMGCR–IMNM, even without concomitant GC or other immunosuppressive agent, we opted for a GC-free approach through shared-decision making in light of patient’s preference regarding potential GC side effects with his comorbidities. As he lived a considerable distance from any center, where IVIg infusions could be offered, and given the patient was unable to drive himself due to his symptoms we opted for SCIg (0.5 g/kg/week). Within 1 month, his CK decreased and weakness resolved. SCIg monotherapy was tapered over 3 years and this patient remains in remission 7 years after SCIg initiation. The patient did not have any adverse effects related to SCIg use. Conclusions To our knowledge, this is the first case report describing a successful corticosteroid-free management of anti-HMGCR immune-mediated necrotizing myopathy using SCIg as monotherapy. This case highlights the potential for steroids-free induction and maintenance strategies in IMNM. Larger studies are required to confirm the effectiveness and safety of SCIg in IMNM and other subtypes of IIM, and to provide guidelines for dosing recommendations.Type d'Item : Item , The diagnostic accuracy of left ventricular ejection fraction assessment between visual and artificial intelligence-based algorithms on bedside ultrasound(2026-08-31) Kolobaric, Nikola; Beauregard, Nickolas; Barbour, William; Prosperi-Porta, Graeme; Parlow, Simon; Di Santo, Pietro; Abdel-Razek, Omar; Jung, Richard; Bradford, William B.; Tsang, Miranda; Pacifici, Stefano; Ramirez, F. D.; Huggins, Gordon S.; Bugeja, Ann; Simard, Trevor; Mathew, Rebecca; Hibbert, Benjamin; Motazedian, Pouya; Marbach, Jeffrey A.Abstract Background Focused cardiac ultrasound (FoCUS) has become the standard of care for bedside assessments of cardiac function. With the integration of artificial intelligence (AI), there is limited evidence comparing it to bedside visual assessments by experienced users. Methods In our prospective study conducted at Tufts Medical Center in Boston, Massachusetts from December 2020 to March 2022, patients ≥ 18 years requiring a TTE were recruited by convenience sampling. They each underwent FoCUS LVEF classification by AI and bedside visual assessment, with TTE as reference. LVEF was calculated by Simpson’s biplane method of disks in AI-FoCUS and TTE, and visual global assessment by the bedside sonographer. Data analysis was completed in October 2025. Results Our 215 participants had a median age of 63 (IQR 49–73) years with 83 (38.6%) being female. AI-FoCUS assessments showed good agreement with TTE (intraclass correlation coefficient 0.84, 95% CI: 0.80–0.88), while visual assessments had stronger concordance (intraclass correlation coefficient 0.97, 95% CI: 0.96–0.98). Categorization of LV dysfunction severity showed excellent agreement with TTE for both AI-FoCUS (kappa 0.89, 95% CI: 0.84–0.94) and visual estimate (kappa 0.96, 95% CI: 0.92–0.99). For AI-FoCUS, the area under the curve (AUC) for identifying an abnormal LVEF (< 50%) was 0.9779 (95% CI: 0.9591–0.9967) with sensitivity 90.9% (95% CI: 88.1–100), specificity 95.6% (95% CI: 92.6–98.6), positive predictive value (PPV) 0.79 (95% CI: 0.66–0.92) and negative predictive value (NPV) 0.98 (95% CI: 0.96–1.00). For visual estimate, the AUC was 0.9961 (95% CI: 0.9915–1.000) with sensitivity 90.9% (95% CI: 88.1–100), specificity 97.8% (95% CI: 95.7–99.9), PPV 0.88 (95% CI: 0.77–0.99) and NPV 0.98 (95% CI: 0.96–1.00). Conclusion AI-assisted FoCUS LVEF assessments provide accurate estimates for the presence and severity of LV dysfunction but are outperformed in the latter by experienced bedside users. Graphical AbstractType d'Item : Item , Elucidating the Molecular Mechanisms of Host Susceptibility to Salmonella Typhimurium Infection by IFN-I Signaling(Université d'Ottawa / University of Ottawa, 2026-08-31) Chehab El Din El Hamra, Rayan; Sad, Subash; Blais, AlexandreSalmonella enterica serovar Typhimurium (ST) is considered a non-typhoidal strain of Salmonella, which causes progressive diseases in susceptible mice, resembling typhoid-like fever. Salmonella infection occurs due to the ingestion of contaminated food and water supplies and is a major public health concern. In immunocompromised individuals, this strain can be fatal, with reports of an estimated 2 million deaths each year. This makes understanding the molecular mechanisms behind ST infection of vital importance. Type I interferons (IFN-I) are crucial in the immune response, but their role against bacterial infections remains elusive. While IFN-I signaling is critical for antiviral immunity, we show that IFN-I signaling promotes susceptibility to ST infection. Despite reduced innate immune pathways such as TLR and IFNγ signaling, Ifnar1⁻ᐟ⁻ BMDMs exhibit enhanced resistance against ST, indicating the involvement of non-canonical protective mechanisms. We find that the induction of interferon-stimulated genes by IFN-I signaling suppresses protein synthesis, which limits antimicrobial activity during ST infection. In contrast, Ifnar1⁻ᐟ⁻ BMDMs display increased protein synthesis and metabolic activity, supporting improved intracellular control of ST. Notably, Irf9⁻ᐟ⁻ BMDMs display increased and sustained STAT1 signaling while maintaining this metabolically active state, resulting in enhanced survival and resistance compared to Ifnar1⁻ᐟ⁻ mice. Together, these findings demonstrate that IFN-I signaling drives translational repression to restrict immunometabolic responses necessary for controlling ST infection.Type d'Item : Item , Food Screeners for Adolescents: A Hybrid Review Focused on Their Psychometric Properties(Université d'Ottawa / University of Ottawa, 2026-08-31) Roe, Emma; Tugault-Lafleur, Claire N.Food screeners are a low-cost, low-burden option for nutrition surveillance, but their number and variability complicate tool selection for adolescents. This review aimed to describe food screeners used among adolescents in high-income countries and evaluate their validity and reliability. A hybrid approach was used: a scoping review to identify existing screeners and a systematic review to assess psychometric quality. Screeners with ≤30 items targeting healthy adolescents aged 10-17 years were eligible. Forty-seven screeners were identified through both searches. Instruments averaged 16 items with 22 including portion size questions, and 26 assessing alignment to dietary guidelines. Twenty-six screeners had psychometric evidence, and 18 met quality criteria. Construct (convergent) validity was most frequently examined, with most estimates falling in the poor-moderate range, whereas reliability was generally stronger, with most instruments demonstrating acceptable test-retest performance. Findings highlight substantial variability and key gaps in adolescent food screener evaluation.Type d'Item : Item , Income-tested and in-kind: The material wellbeing effects of the Canadian Dental Care Plan(2026-08) Notten, GerandaRich countries increasingly rely on income-testing and their income-tax system to deliver both cash and in-kind transfers to recipients. This research measures the material wellbeing effects of the in 2023 introduced Canadian Dental Care Plan (CDCP). Using four measures of material deprivation, it reveals material wellbeing effects that are either missed entirely or are misestimated by income (poverty) measures. It further demonstrates three new Cost-Effectiveness Ratios (CER) that further contribute to filling current evidence gaps. The CDCP is income-tested and covers dental care costs of households with an income below $90,000 who do not have a dental plan. Using microdata from 2023 and 2025, the research uses the staggered introduction of the CDCP and the doubly robust difference-in-difference estimator to estimate the impact of the CDCP on seniors. The research estimates that the CDCP reduced the incidence of dental care deprivation among seniors by 8.7 percentage points, which amounts to a 62 percent decline compared to the 2023 baseline. Further estimates indicate, among others, that the CDCP averted close to 700 thousand cases of dental care deprivation at a cost of about 50 million dollar per percentage point reduction in dental care deprivation. This suggests that the CDCP made a substantive contribution toward addressing the specific barrier it was designed to reduce. More broadly, this research shows that outcome-based measures of material wellbeing, such as dental care deprivation, provide unique insights on the material wellbeing effects of social and health programs and thereby also offer novel opportunities for assessing their cost-effectiveness.