Predictors of disease course in systemic juvenile idiopathic arthritis.

PURPOSE: To identify potential predictors of the disease course of systemic juvenile idiopathic arthritis (sJIA) at the time of diagnosis.

METHODS: This retrospective observational study was conducted in patients diagnosed with sJIA in our hospital between April 2009 and October 2023. The relationship between the disease course of sJIA patients and demographic, clinical, laboratory findings and complications were analyzed.

RESULTS: Of the 51 patients diagnosed with sJIA, 26 (51%) patients had monocyclic, 7 (13.7%) polycyclic and 18 (35.2%) persistent disease course. 3 (5.8%) patients had a persistent disease course with persistent arthritis developed flares with systemic manifestations during follow-up. The presence of arthritis, polyarticular involvement, and hip involvement at the time of diagnosis were associated with persistent disease course (p=0.009, p=0.003, p=0.003). Serositis and higher white blood cell and neutrophil counts at the time of diagnosis were associated with a monocyclic disease course (p=0.034, p=0.002, p=0.008). However, no significant correlation was found between macrophage activation syndrome (MAS) and disease course (p=1).

CONCLUSIONS: Systemic JIA patients with polyarthritis and hip involvement at disease onset may develop a persistent course. Although MAS is an important complication of sJIA, its effect on the course of the disease was not found in this study.