Annals of the Rheumatic Diseases (ARD)EULAR/PReS Recommendations for the Diagnosis and Management of Still’s Disease, Comprising Systemic Juvenile Idiopathic Arthritis and Adult-Onset Still’s Disease

✅ Guideline Update

A joint EULAR/PReS task force issued 14 consensus recommendations declaring systemic JIA and adult-onset Still’s disease the same condition. The guideline establishes diagnostic operational definitions not requiring arthritis, defines clinically inactive disease and remission targets, and prioritizes early biologic therapy over glucocorticoids.

Clinical Considerations

• Arthritis is not required for diagnosis; fever, transient salmon-pink rash, and elevated inflammatory markers (CRP, ferritin, neutrophilic leukocytosis) are the key operational features
• IL-1 or IL-6 inhibitors should be initiated as early as possible, ideally within 3 months of symptom onset, to limit glucocorticoid exposure and reduce risk of chronic persistent disease
• Macrophage activation syndrome (MAS) occurs in 15-20% of patients and can develop at any disease stage, including during otherwise well-controlled treatment; daily ferritin monitoring is advised when MAS is suspected
• Still’s disease-related lung disease, an emerging severe complication linked to younger age, Down syndrome, and recurrent MAS, should not prompt discontinuation of IL-1/IL-6 inhibitors despite a proposed hypersensitivity mechanism

Practice Applications

• Recognize that arthritis may appear weeks after fever onset and should not delay diagnosis or treatment
• Consider early IL-1 or IL-6 inhibitor initiation rather than prolonged glucocorticoid-first strategies
• Monitor ferritin trends, liver function, and cytopenias closely in patients with persistent fever or clinical deterioration
• Avoid withdrawing IL-1 or IL-6 inhibitors solely due to emerging lung disease without expert center consultation