[A case of macrophage activation syndrome developed with systemic juvenile rheumatoid arthritis].

We reported a child of macrophage activation syndrome (MAS) associated with the course of systemic juvenile rheumatoid arthritis (sJRA). The clinical and laboratory findings in our case was ascribed to the overproduced inflammatory cytokines especially TNF-alpha by activated macrophages. Moreover, macrophage-colony stimulating factor (M-CSF) was also elevated in the active phase of the disease, and decreased in the convalescent phase, indicating that M-CSF can be the most potent stimulator of macrophages to produce inflammatory cytokines. Cyclosporine A along with plasmaexchange and corticosteroid, instead of VP16 or other immunosuppresive agents, was effecting in the management of this severe, life-threatening MAS.