Treatment of systemic juvenile idiopathic arthritis

bDMARD: biologic DMARD; CRP: C-reactive protein; csDMARD: conventional synthetic DMARD; DMARD: disease-modifying antirheumatic drug; ESR; erythrocyte sedimentation rate; IL: interleukin; JAK: janus kinase; MAS: macrophage activation syndrome; MTX: methotrexate; sJIA: systemic juvenile idiopathic arthritis; TNF: tumor necrosis factor.

* Suggestive features of MAS include unremitting fever and rash, hepatic dysfunction, and/or extremely high serum ferritin. Additional features in sJIA that may suggest evolving MAS include decreasing cell counts and ESR and/or increasing ferritin in the setting of persistent sJIA symptoms. For more information on the diagnosis of MAS, refer to UpToDate content on complications of sJIA.

¶ Moderate to severe symptoms or signs of systemic disease may include persistent fever, lymphadenopathy, hepatomegaly, splenomegaly, and/or serositis. For more information, refer to UpToDate content on clinical manifestations of sJIA.

Δ Examples of disabling arthritis include involvement of >5 joints and/or interference with daily activities.

◊ For the evaluation and diagnosis of MAS, refer to UpToDate content on complications of sJIA.

§ For choice of therapy, refer to UpToDate content on treatment of MAS in the setting of sJIA. Alternative therapy with MTX and systemic glucocorticoids may be preferred by some providers and/or patients and families, based on different adverse effect profiles among various immunosuppressive agents.

¥ Glucocorticoids generally should be avoided unless the possibility of malignancy, which may cause a similar presentation, has been excluded.

‡ The addition of intraarticular glucocorticoids may be beneficial for arthritis affecting a large- to medium-sized joint that is accessible for injection and which is causing significant functional impairment.

† Features suggestive of persistent disease include ongoing fever, rash, arthritis, serositis, and/or persistent or worsening CRP elevations.