Tocilizumab for uncontrollable systemic inflammatory response syndrome complicating adult-onset Still disease

Rationale: Adult-onset Still disease (AOSD) is a rare systemic inflammatory disease of unknown etiology characterized by evanescent salmon-pink rash, fever spikes, arthralgia, and lymphadenopathy. AOSD usually has a good prognosis, but it can sometimes be fatal, especially when it is complicated by systemic inflammatory response syndrome (SIRS) and multiple organ failure. Patient concerns: A previously healthy 26-year-old woman was referred to our hospital for persistent high fever and mild systemic edema. Five days later, the patient presented with dyspnea, hypotension, and anuria. Anasarca developed with massive pleural effusion, ascites, and systemic edema, resulting in an increase of 47 kg in body weight. Diagnoses: The patient was diagnosed as AOSD after infection, malignancy, hematologic disorders, and other autoimmune diseases were excluded. Interventions: We administered tocilizumab, an IL-6 receptor inhibitor, intravenously in addition to cyclosporine, prednisolone, plasma exchange, and continuous hemodiafiltration. Outcomes: The patient's systemic condition improved. After stabilization by all medications, the patient was managed and responded to tocilizumab alone. To the best of our knowledge, this was the first case of severe SIRS complicating AOSD that was successfully treated with an anti- IL-6 receptor antibody. Lessons: SIRS should not be overlooked in a patient with steroid-resistant AOSD and edema. Inhibitors of the IL-6 receptor can be used safely and effectively to control AOSD complicated with severe SIRS.