How is adult onset Stills disease treated?
• Mild disease: occurs in 25% cases with fever, rash, and arthralgias. In these patients, NSAIDs (naprosyn 500 mg BID) alone can adequately control AOSD. If symptoms are not controlled in 2 weeks, they are switched to low-dose prednisone (0.5 mg/kg/day).
• Moderate disease: patients who present with high fever, disabling arthritis, and mild internal organ involvement are started on high-dose prednisone (1.0 mg/kg/day) immediately. If prednisone cannot be tapered to a low dose without disease recurrence, methotrexate is added for patients with predominant articular symptoms. There is little experience using any of the other disease-modifying antirheumatic drugs (DMARDs) (antimalarials, azathioprine, mycophenolate mofetil, leflunomide, cyclosporine). Sulfasalazine should probably be avoided owing to a high rate of side effects.
• Severe disease: patients who present with life-threatening organ manifestations (liver necrosis, cardiac tamponade, MAS/RHL, DIC) are treated with pulsed methylprednisolone followed by high-dose prednisone and early use of biologic therapy.
• Resistant disease: patients who have life-threatening presentations or patients who continue to require high-dose corticosteroids (>20 mg/day) in spite of 2 months of therapy with methotrexate or another DMARD may benefit from therapy with one of the biologics. Patients with AOSD have high serum levels of TNFα, IL-1, IL-6, and IL-18. Consequently, therapy that blocks one of these cytokines including anti-TNF therapy, IL-1 inhibitors (anakinra, canakinumab, rilonacept), and IL-6 inhibitors (tocilizumab) have induced remission in 70%–80% of AOSD patients. IL-1 inhibitors and tocilizumab are more effective than TNF inhibitors especially for systemic manifestations. Patients with chronic articular disease and few systemic manifestations benefit most from TNF inhibitors (infliximab) and methotrexate. Rituximab, abatacept, intravenous immunoglobulin (IVIG), and stem cell transplant have been used for resistant cases. An IL-18-binding protein (tadekinig alpha) is currently in clinical trials.
