A case of adult-onset Still disease complicated by macrophage activation syndrome and toxic epidermal necrolysis.

A 56-year-old woman with 1-year recurrent fever, rash, joint swelling (acute exacerbation) was diagnosed with adult-onset Still disease (AOSD) per 1992 Yamaguchi criteria. She initially improved with methylprednisolone, tocilizumab, methotrexate, and iguratimod but relapsed after discontinuing methylprednisolone. Twenty-four hours after first Re Du Ning injection, she developed progressive rash (extensive polymorphic erythema, bullae, and >30% body surface epidermal detachment), high fever, organ impairment, and coagulopathy and was diagnosed with AOSD complicated by macrophage activation syndrome (2004 haemophagocytic lymphohistiocytosis guidelines), toxic epidermal necrolysis, myocardial injury, hepatic impairment, and disseminated intravascular coagulation. Treatment included dexamethasone, methylprednisolone, plasma exchange, cyclosporine, anakinra, ganciclovir, voriconazole, intravenous immunoglobulin, and supportive care, leading to marked improvement in lesions. This case highlights rare AOSD complications and anakinra's efficacy.