RESUMO
Adult onset Still's disease (AOSD) is a systemic autoinflammatory disorder that presents with recurrent fever, extreme fatigue, and joint pain. Pulmonary involvement is not uncommon and, although rare, severe pneumonitis can progress to respiratory failure. Still's disease-associated pneumonitis is generally treated with immunosuppressive agents, but improvement in our understanding of systemic inflammatory processes led us to explore alternative agents. Anakinra is an interleukin-1 receptor antagonist used to treat autoinflammatory disorders resistant to immunosuppressive therapy. Several case reports have demonstrated efficacy of anakinra in treating AOSD, but its relevance in cases complicated with severe pneumonitis has not been examined. Our patient's disease activity was not controlled with systemic steroids and cyclophosphamide. Treatment with anakinra led to a dramatic clinical response. This is the first reported case of AOSD with severe pneumonitis refractory to conventional therapy successfully treated with anakinra.