Evaluation and Treatment of Childhood Enthesitis-Related Arthritis.

Abstract

Enthesitis-related arthritis (ERA) is phenotypically distinct from the other categories of juvenile idiopathic arthritis (JIA). Therefore, patients with ERA warrant distinct pharmacological treatments tailored to their disease process. The advent of biologic disease-modifying agents (biologics) has revolutionized the treatment of ERA. Biologics are drugs that are genetically engineered from a living organism (such as a virus, gene, or protein) to modify signaling along the inflammatory pathway and thereby modulate the immune system. There has been movement over the last decade to categorize and treat patients with spondyloarthritis on the basis of axial disease since axial involvement warrants treatment with a biologic, in particular, a tumor necrosis factor alpha (TNF-α) blocker. To help identify ERA patients correctly for research purposes, the use of ultrasound with Doppler (USD) and/or whole-body magnetic resonance imaging (MRI) is being increasingly used; their role in clinical practice, however, is still undetermined. We strongly recommend that MRI of the pelvis be performed for any ERA patient in whom axial disease is suspected as its presence may influence the medication regimen, specifically initiation of a biologic. The recent development of a spondyloarthritis (including ERA)-specific disease activity tool called the Juvenile Spondyloarthritis Disease Activity Score (JSpADA) will hopefully allow pediatric rheumatologists to better monitor disease activity over time. Over the last decade, there has been a plethora of research to help advance our understanding of the etiopathogenesis of spondyloarthritis. Future promising treatments for ERA are evidenced by research implicating the role of the IL-12/23 and IL-17 axis in spondyloarthritis. Investigations examining the microbiome will further elucidate the interactions between genetics and the environment that lead to the development of ERA. With more randomized therapeutic trials and more microbiome and genetics-related research, we will likely see the development of targeted therapies for the treatment of ERA in the near future.