Juvenile vs. Adult-Onset Spondyloarthritis: Uncovering Similarities and Differences

The primary objective of this investigation is to systematically assess the resemblances and distinctions between enthesitisrelated arthritis (ERA), which serves as a pediatric analog to ankylosing spondylitis (AS), and AS.

A cross-sectional analysis was conducted within a pediatric rheumatology facility and an adult rheumatology institution. Demographic and clinical attributes were juxtaposed between individuals diagnosed with AS and those with ERA.

A cumulative total of 200 subjects (101 minors, 99 adults) were scrutinized. The prevalence of peripheral arthritis was significantly elevated in ERA (54.5%) compared to AS (21.2%, P < .001), whereas sacroiliitis, axial involvement, and morning stiffness were more prevalent in AS. Nonsteroidal anti-inflammatory drugs constituted the predominant initial therapeutic approach (99% vs. 91.9%, P = .01). Patients with ERA exhibited a higher utilization of corticosteroids (35.6% vs. 11.1%, P < .001) and diseasemodifying antirheumatic drugs (DMARDs) (87.1% vs. 60.6%, P < .001), with no notable variance in the application of biological agents. At the final follow-up assessment, 24.8% of ERA patients were free from medication, whereas no AS patients achieved a medication-free status.

An increased volume of scientific evidence is requisite concerning the attributes of ERA, which is presently regarded predominantly within the framework of juvenile spondyloarthritis, distinguishing it from its adult counterpart; this study serves as an observational cohort investigation that underscores this imperative. Despite the observable differences and similarities between ERA and AS, further extensive studies incorporating inflammatory biomarkers are essential to ascertain whether these conditions represent discrete diseases or exist within a broader disease continuum. Cite this article as: Unan MK, Özaslan Z, Dilek G, Şahin N, Sönmez HE, Nas K. Juvenile vs. adult-onset spondyloarthritis: Uncovering similarities and differences. Arch Rheumatol. 2026;41(2):90-99.