Presentation of enthesitis-related arthritis and juvenile-onset spondyloarthritis: a cross-sectional study in a pediatric and adult clinic

Adv Rheumatol. 2024 May 8;64(1):39. doi: 10.1186/s42358-024-00378-8.

Abstract

Background: Juvenile idiopathic arthritis (JIA) comprises a whole spectrum of chronic arthritis starting before 16 years of age. The study aims to explore the clinical and demographic descriptors, treatment, and disease progression of enthesitis-related arthritis (ERA) in comparison with juvenile-onset spondyloarthritis (SpA).

Methods: Cross-sectional analysis of consecutive patients in two dedicated clinics, with a single visit and retrospective case-notes review. Arthritis, enthesitis and sacroiliitis were evaluated by scoring disease activity and damage. Continuous variables were reported by median, interquartile range; categorical variables were reported by the frequency comparison of the two groups.

Results: Thirty-three cases were included, being 23 (69.7%) with ERA. The median age at diagnosis was 12.5 y (SpA) vs. 9 y (ERA) (p < 0.01); the time from symptom onset to diagnosis was 5.5 y (SpA) vs. 1.5 y (ERA) (p < 0.03). In both groups, the predominant presentation was a single joint or < 5 lower limb joints and asymmetric involvement, with a high frequency of enthesitis. There was a higher frequency of mid-tarsal and ankle synovitis in the ERA group and hip involvement in those with SpA. The comparison of the frequency of spine symptoms at presentation, 30% SpA vs. 21.7% ERA (p = 0.7), was not significant, and radiographic progression to spinal involvement occurred in 43.5% of ERA patients. The median time for spinal progression and age at onset was 2.2 and 12 y for ERA, and 4 and 16.5 y for SpA, respectively. Activity and damage scores were not significantly different between the groups. Treatment comparison resulted in 91.3% of ERA and 100% SpA being treated, predominantly with NSAIDs in both groups, followed by DMARDs and biologics, with a higher frequency of biologics in SpA.

Conclusion: The main differences were the late diagnoses of SpA, and the hip and spine involvement, with higher frequency of biologic treatment in juvenile-onset SpA compared to ERA.

Keywords: Classification; Enthesitis-related arthritis; Juvenile idiopathic arthritis; Outcome; Spondyloarthritis; Spondyloarthropathy.

MeSH terms

  • Adolescent
  • Adult
  • Age of Onset
  • Antirheumatic Agents* / therapeutic use
  • Arthritis, Juvenile* / complications
  • Arthritis, Juvenile* / diagnosis
  • Arthritis, Juvenile* / drug therapy
  • Child
  • Cross-Sectional Studies
  • Disease Progression*
  • Enthesopathy / diagnostic imaging
  • Enthesopathy / etiology
  • Female
  • Humans
  • Male
  • Retrospective Studies
  • Sacroiliitis / diagnostic imaging
  • Spondylarthritis* / complications
  • Spondylarthritis* / diagnosis
  • Spondylarthritis* / drug therapy

Substances

  • Antirheumatic Agents