Successful remission induced by plasma exchange combined with leukocytapheresis against refractory systemic juvenile idiopathic arthritis.

Systemic juvenile idiopathic arthritis (sJIA) is an inflammatory cytokine-related disorder associated with overproduction of interleukin (IL)-6, IL-1β, and IL-18. Macrophage activation syndrome (MAS) is a critical and lethal complication of sJIA. Therefore, prompt induction of remission in the active phase of sJIA is important for prevention of MAS. However, treatment of corticosteroid-resistant sJIA is still challenging. We propose a new strategy to induce remission in the active phase of sJIA. A 7-year-old boy with new-onset sJIA was treated with oral prednisolone, methylprednisolone pulse therapy, and parenteral cyclosporine, but he continuously showed remittent high fever, arthralgia, skin rash, and elevation of inflammatory markers, including hyperferritinemia. Because of impending MAS, plasma exchange was started, but he was resistant to plasma exchange. Therefore, we combined leukocytapheresis with PE. After five PE and two leukocytapheresis sessions, he finally achieved remission in accordance with a reduction in inflammatory cytokines. Elevated serum tumor necrosis factor-α, interferon-γ, and IL-12 levels returned to normal 10 days after initiating plasma exchange combined with leukocytapheresis, with a reduction in white blood cell count. In conclusion, plasma exchange combined with leukocytapheresis is a new alternative option to induce remission for patients with methylprednisolone pulse therapy- or cyclosporine-refractory sJIA.