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Study Type: Exploratory biomarker analysis (serum and transcriptomic) of patients from a randomised withdrawal study.

Key Question: Can serum markers or whole-blood gene expression signatures predict successful versus unsuccessful canakinumab tapering in sJIA patients in remission?

Key Findings:

• Lower baseline serum sCD163, CXCL9, IL-1RA and IL-18 were associated with successful tapering (79 patients; 71 with gene expression data).
• RNA-Seq showed future non-responders had lower type I interferon-induced and higher erythropoiesis-related gene expression.
• A nine-gene NanoString composite score (including IL1B, TNFAIP3, FAS) discriminated outcomes with modest accuracy (AUC 0.71).

Clinical Relevance: If validated, such biomarkers could support individualised tapering of costly IL-1 blockade in sJIA/Still's disease, though they are not yet usable in routine NHS practice.

Limitations: Modest discrimination (AUC 0.71) with no reported external validation, and the gene panel was derived from the same cohort (risk of overfitting).

Study Type: Post hoc analysis of RCT data (PEXIVAS) with prognostic model derivation and internal validation.

Key Question: Can baseline and remission-point clinical variables estimate an individual's risk of first relapse within 2 years of remission in severe AAV?

Key Findings:

• Of 649 participants achieving remission, 100 relapsed within 2 years.
• Final model predictors: sex, induction agent (oral cyclophosphamide or rituximab), ANCA subtype, non-haemorrhagic respiratory or mucous membrane/eye involvement at presentation, and eGFR at remission.
• Discrimination was modest (optimism-corrected AUC 0.709, 95% CI 0.707-0.710); calibration slope 0.99 (95% CI 0.65-1.34).

Clinical Relevance: A validated tool could help individualise relapse monitoring and decisions on maintenance therapy duration, but it is not yet ready for UK clinical use.

Limitations: Internal validation only, in a trial population restricted to severe disease (eGFR <50 or diffuse alveolar haemorrhage), limiting generalisability; external validation is still required.

Study Type: Laboratory/translational study (primary human synovial fibroblasts and tissue; in vitro gene silencing, transcriptomic and epigenetic analysis).

Key Question: How does developmental positional identity, specifically 5' HOXD gene expression, shape joint-specific synovial fibroblast behaviour in adult tissue and arthritis?

Key Findings:

• HOXD10, HOXD11 and HOXD13 were expressed selectively in synovial fibroblasts from distal joints, with epigenetic mechanisms maintaining this anatomical restriction.
• Silencing 5' HOXDs produced transcriptional changes resembling joint-specific differences seen in RA; HOXD13 regulated primary cilia function, cell-cycle control, DNA damage response and genome stability.
• Joint-specific differences were also found in cilia morphology, cell-cycle regulation and DNA repair capacity. No effect sizes, sample sizes or p-values were provided in the abstract.

Clinical Relevance: Offers a mechanistic basis for why disease patterns and treatment responses differ between joints in RA, relevant to future stromal-targeted therapy where current NHS treatment remains immune-directed.

Limitations: Findings derive from in vitro silencing experiments in cultured fibroblasts, with no in vivo or clinical validation, so causal relevance to patient disease is unproven.

Study Type: Mechanistic interventional cohort study (single-arm perturbation design) with exploratory post-hoc analysis; cohort size not reported in abstract.

Key Question: How does dual BAFF/APRIL blockade with telitacicept remodel pathogenic antiphospholipid antibody (aPL) responses in triple-positive aPL patients?

Key Findings:

• Telitacicept caused broad B-lineage contraction, with consistent IgM and IgA aPL reductions but heterogeneous IgG aPL suppression.
• Peripheral B-cell and plasmablast turnover was extensive, whereas class-switched marrow plasma cells showed greater clonal continuity.
• In a post-hoc analysis, incomplete IgG aPL suppression was associated with persistence of pretreatment marrow IGHG⁺ clonotypes. Overall marrow IGHG⁺ plasma-cell abundance did not distinguish responders from non-responders.

Clinical Relevance: Suggests BAFF/APRIL blockade may be insufficient alone to suppress IgG aPL in triple-positive disease, which matters given the limited non-anticoagulant options in refractory APS; telitacicept is not NHS-available.

Limitations: Sample size and clinical outcomes (thrombosis, obstetric events) are not reported, and the key IgG-persistence finding derives from an exploratory post-hoc analysis, so it is hypothesis-generating only.

Study Type: Two-stage case-control epigenetic study (discovery and independent validation cohorts)

Key Question: Can peripheral-blood DNA methylation signatures distinguish gout from asymptomatic hyperuricaemia and normouricaemia?

Key Findings:

• Differentially methylated regions across all three group comparisons mapped to 84 genes overlapping gout/urate risk loci (including HLA-DRB1, TAP2, GNAS); 113 methylation sites were validated in an independent cohort.
• A methylation-only classifier outperformed clinical variables for gout vs non-gout controls (AUC 0.91 vs 0.78; P = 0.032).
• For gout vs asymptomatic hyperuricaemia, combining methylation with clinical variables raised AUC from 0.67 to 0.87 (P = 0.018).

Clinical Relevance: Methylation profiling could eventually identify which hyperuricaemic patients are at risk of progressing to gout, informing urate-lowering therapy decisions, though this is not yet applicable to NHS practice.

Limitations: Small, cross-sectional case-control design without prospective validation, so predictive value for progression to gout is untested.

Study Type: Descriptive 10-year follow-up of a randomised controlled trial (CRESPA), single cohort analysis; not a randomised comparison at this timepoint.

Key Question: What proportion of patients with early peripheral SpA (symptom duration ≤12 weeks), treated initially with golimumab or placebo, achieve clinical and drug-free remission at 10 years, and what predicts this?

Key Findings:

• 49/60 patients reassessed (mean 10.5 years): 81.6% (40/49) in clinical remission; 30.6% (15/49) in sustained drug-free remission.
• Absence of baseline psoriasis predicted drug-free remission (OR 9.1; 95% CI 1.8–50); 48.1% (13/27) of non-psoriatic pSpA were drug-free. Sex, age, HLA-B27 and initial treatment allocation did not predict remission.
• Quality of life and physical function were significantly better in those in remission.

Clinical Relevance: Supports the concept of a window of opportunity in early pSpA, particularly non-psoriatic disease, and may inform discussions on treatment withdrawal.

Limitations: Small sample with 18% loss to follow-up, wide confidence intervals, and no long-term comparator, so the effect of early golimumab cannot be separated from natural history.

Study Type: International cross-sectional web-based survey of physicians (descriptive; expert-panel designed, October-December 2023)

Key Question: How is macrophage activation syndrome (MAS) treated in real-life practice across different underlying diseases, regions, subspecialties and drug-access settings?

Key Findings:

• 287 physicians from 64 countries responded (mostly paediatric rheumatologists with >5 years' experience). Glucocorticoids, particularly IV methylprednisolone, were first-line across all MAS subtypes, and 44% used them as monotherapy.
• Anakinra, ciclosporin and IVIG were the most commonly added agents; anakinra was preferentially used in Still's disease-associated MAS, with marked variation by disease and region.
• Limited availability of anakinra and emapalumab was associated with greater reliance on steroid monotherapy.

Clinical Relevance: Highlights substantial global variation in MAS management and the absence of consensus beyond steroids, reinforcing the case for standardised pathways and equitable access to targeted agents in the UK and elsewhere.

Limitations: Self-reported survey with no patient-level outcome data, and a respondent pool dominated by paediatric rheumatologists, limiting generalisability (including to adult-onset MAS) and the ability to link treatment choices to outcomes.

Study Type: Preclinical experimental study (murine models: pharmacological AHR activation and Ahr knockout), with a small human case series (n=4, glycogen storage disease).

Key Question: Does the Aryl Hydrocarbon Receptor (AHR), a mediator of environmental pollutant toxicity, regulate renal uric acid excretion, and by what mechanism?

Key Findings:

• Dioxin-like AHR agonists reduced renal uric acid excretion in mice; Ahr deletion increased it.
• AHR did not alter renal uric acid transporters. Instead, it modified hepatic gluconeogenesis and lactate metabolism, with raised lactate competing with urate for exchange in the proximal tubule.
• Four patients with glycogen storage disease supported gluconeogenesis as a determinant of uric acid homeostasis (no effect sizes or confidence intervals reported in the abstract).

Clinical Relevance: Offers a plausible mechanism linking environmental pollutants to hyperuricaemia and gout, and implicates AHR and hepatic gluconeogenesis as potential novel therapeutic targets beyond current urate-lowering therapy; no immediate change to UK practice.

Limitations: Findings rest primarily on mouse models with only four human participants, so translation to gout in the general population remains unproven.