Canadian Rheumatology Today

Interstitial Lung Disease for the Rheumatologist: Pearls and Insights

Laurence Poirier-Blanchette — 2025-12-19

Interstitial lung disease (ILD) is a potentially life-threatening complication of systemic autoimmune rheumatic diseases (SARDs). Its prevalence varies according to the underlying SARD, being highest in anti-synthetase and anti‑melanoma-differentiation-associated protein 5 (MDA5) syndromes, but affecting the greatest number of individuals in rheumatoid arthritis due to its higher overall frequency. Because ILD onset may precede, coincide with, or follow SARD diagnosis, rheumatologists may uncover an undiagnosed SARD during ILD evaluation or, conversely, detect ILD through screening of patients with established SARD. The spectrum of SARD-ILD is broad: some patients have mild, stable disease, others experience slowly progressive disease, and some deteriorate rapidly despite treatment, leading to oxygen dependence, lung transplantation, or death. Drug therapies, including immunosuppressive and anti‑fibrotic agents, can slow the progression of SARD-ILD.

This article addresses three key clinical questions pertinent to rheumatologists. First, we explore clinical, serological, and morphological features that can aid in diagnosing SARD in patients with ILD, offering practical pearls. Second, we examine screening—covering who to screen, when, how, and at what frequency. Finally, we outline our approach to SARD-ILD management.

Latest Developments in Imaging for Axial Disease in Psoriatic Arthritis

Walter P. Maksymowych — 2025-12-19

Axial disease in psoriatic arthritis (axPsA), affecting the sacroiliac joints (SIJ) and spine, is recognized as one of the domains in the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) treatment recommendations for psoriatic arthritis (PsA). Accurate recognition of this manifestation is crucial for comprehensive management of this disease. It is defined according to both clinical and imaging features. Clinically, inflammatory back pain (IBP) is a key feature; however, findings from a recent Canadian inception cohort study—Screening for Axial Spondyloarthritis in Psoriasis, Iritis, or Colitis Cohorts 1 and 2 (SASPIC1 and 2)—which included patients with psoriasis and undiagnosed back pain, showed no differences in the frequency of IBP or non-steroidal anti-inflammatory drug (NSAID) responsiveness between those diagnosed with axPsA and individuals with other causes of chronic back pain. Similarly, data from the global Axial Involvement in Psoriatic Arthritis (AXIS) cohort revealed only minor numerical differences in NSAID responsiveness or frequency of IBP, according to the ASAS criteria, between participants with and without axial involvement when evaluated by central reviewers. Recent post-hoc studies of clinical trials in PsA have attempted to identify axPsA according to a Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) threshold of ≥4. However, MRI-based assessment of axPsA in a large European cohort of 581 PsA patients, recruited across 17 European registries within the EuroSpA network, indicated that a BASDAI ≥4 did not discriminate PsA patients with axial disease from those without. Moreover, only 25–45% of patients with radiographic features of axPsA have been reported to have IBP, with some patients being clinically perceived as asymptomatic. Additionally, axSpA-based IBP criteria have demonstrated limited specificity for axPsA. Studies using MRI have reported poor correlation between sacroiliitis on imaging and both the presence and type of back pain.

Management of Adult Patients with Lupus Nephritis: Therapeutic Algorithm Based on the Current Treatment Guidelines

Konstantinos Tselios — 2025-12-19

Lupus nephritis (LN) is one of the most significant manifestations of systemic lupus erythematosus (SLE) affecting approximately 35–40% of patients in large cohort studies. It is usually diagnosed in the early phases of the disease; among those with LN, approximately 80% are diagnosed at or shortly after disease onset. LN is characterized by histological and clinical heterogeneity and substantially affects survival. A meta-analysis of 18,309 LN patients reported a 10-year risk for the development of end-stage kidney disease (ESKD) of nearly 17% overall and 33% among those with LN class IV (diffuse proliferative form). Early detection and timely management are essential for optimizing outcomes. Given that LN patients are often asymptomatic, it is recommended that all lupus patients, particularly early in the disease course, undergo routine screening every 3–6 months. This includes assessment of proteinuria with urinary protein‑ or albumin‑to‑creatinine ratio (and 24 hour urine protein if indicated), urinary sediment and serum creatinine, regardless of disease activity. If abnormal findings that cannot be explained by alternative causes are detected (proteinuria ≥500 mg/day, active urinary sediment with acanthocytes ≥5% or red blood cell casts or white blood cell casts, increased serum creatinine) a renal biopsy should be performed, as it remains the gold standard for confirming the diagnosis, management planning, and informing the prognosis.

Herein, we present a step-by step approach to the current management of adult LN as recommended by the 2024 American College of Rheumatology (ACR), the 2025 updated European Alliance of Associations for Rheumatology (EULAR), as well as the 2024 KDIGO (Kidney Disease: Improving Global Outcomes) guidelines. New treatment options that will be available in the near future are also discussed briefly.

Should emphasize that the focus is on adult LN approach. The ACR guidelines also discuss children, so I think it should be acknowledged that the focus here is for adults.

If the author is not going to talk about the KDIGO guidelines (which are more recent than the EULAR guidelines), they should be at least acknowledged early on and perhaps just mention some of the differences between ACR/KDIGO as readers it’s been a point of debate and discussion at multiple lupus meetings.