Macrophage activation syndrome is the most frequent life-threatening complication of adult-onset Still's disease. This is a nearly fatal case of a young patient, which has been refractory to corticoste- roids, anakinra, tocilizumab, cyclosporine A, and etoposide, but eventually responded miraculously to salvage therapy with ruxolitinib. We review recent pertinent data related to the therapeutic value of ruxolitinib for macrophage activation syndrome triggered by adult-onset Still's disease.