Drug of choice for resistant macrophage activation syndrome

Macrophage activation syndrome (MAS) is a life-threatening complication of rheumatic diseases, requiring immediate and appropriate treatment. MAS is a disorder related to hemophagocytic lymphohistiocytosis (HLH), which is divided into primary and secondary HLH. The most common autoimmune diseases associated with MAS are systemic juvenile idiopathic ahritis (SJIA), followed by systemic lupus erythematosus (SLE), Kawasaki disease (KD), and juvenile dermatomyositis (JDM). The symptoms of MAS are quite similar to those of many active autoimmune diseases or severe sepsis; therefore, it is quite difficult to make a diagnosis. MAS is still underrecognized, and its treatment is usually delayed, which then leads to high morbidity and moality. The classical signs and symptoms of patients with MAS are a persistent high-grade fever, hepatosplenomegaly, lymph-adenopathy, and hemorrhagic manifestations. The mainstay of MAS treatment is glucocoicoid therapy. Most of the physicians sta with an intravenous methylprednisolone 30 mg/kg/dose (maximum 1 g) for 1-3 days. If the patients respond well to the high dose of methylprednisolone, this is decreased to 2-3 mg/kg/day in a divided dose. If the clinical status of the patients is stable, the physicians change the dosage to oral prednisolone, thus, preparing for a discharge, as well. For the nonresponders, an additional therapy with cyclosporin A 2-7 mg/kg/day is recommended.