-Case Reports-

Clinical Course and Cytokine Profile of Systemic Juvenile Idiopathic Arthritis in a Patient with Trisomy 21

Yujiro Tanabe¹, Haruka Ota¹, Shuya Kaneko², Kanae Tsuno¹, Makoto Watanabe¹, Shingo Yamanishi¹, Hidehiko Narazaki¹, Ryuji Fukazawa¹, Masaki Shimizu² and Yasuhiko Itoh¹

¹Department of Pediatrics, Nippon Medical School, Tokyo, Japan
²Department of Child Health and Development, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan

Trisomy 21 (Down syndrome) is sometimes complicated by congenital heart disease; however, comorbid type I diabetes mellitus and diseases involving autoantibodies, such as Hashimoto disease and Graves disease, are not uncommon. Autoinflammatory diseases such as Kawasaki disease and systemic juvenile idiopathic arthritis are rare. We report a rare case of trisomy 21 with systemic juvenile idiopathic arthritis that responded well to the initial course of methylprednisolone pulse therapy but flared up and was complicated by macrophage activation syndrome (MAS). Subsequent methylprednisolone pulse therapy and cyclosporine resolved this condition. Cytokines were analyzed at several time points during the clinical course and revealed that interleukin-18, interleukin-6, and chemokine ligand 9 levels were elevated at MAS onset in the present patient, even though clinical symptoms had abated. Thus, early analysis of cytokine profiles should be performed to assess MAS risk and determine treatment intensity, even in T21 patients.

J Nippon Med Sch 2023; 90: 419-424

Keywords
cytokine, interleukin-18, macrophage activation syndrome, systemic juvenile idiopathic arthritis, trisomy 21

Correspondence to
Hidehiko Narazaki, MD PhD, Department of Pediatrics, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan
nara@nms.ac.jp

Received, July 11, 2022
Accepted, August 24, 2022