Portal de Periódicos da CAPES

Macrophage Activation Syndrome

2016; Elsevier BV; Linguagem: Inglês

10.1016/b978-0-444-63596-9.00004-9

1571-5078

A. Ravelli, Francesca Minoia, Sergio Davì, Alberto Martini,

Kawasaki Disease and Coronary Complications

Macrophage activation syndrome (MAS) is a serious, potentially life-threatening complication of rheumatic disorders, which is seen most commonly in systemic juvenile idiopathic arthritis (sJIA). It is characterized clinically by unremitting high fever, pancytopenia, hepatosplenomegaly, hepatic dysfunction, encephalopathy, coagulation abnormalities, and sharply increased levels of ferritin. A characteristic feature of the syndrome is seen on bone marrow examination, which frequently, though not always, reveals numerous morphologically benign macrophages exhibiting hemophagocytic activity. MAS is overt in 10% of children with sJIA but may occur subclinically in another 30–40%. Because MAS can pursue a rapidly fatal course, prompt recognition of its clinical and laboratory features and immediate therapeutic intervention are essential. However, it is difficult to distinguish sJIA disease flare, infectious complications, or medication side effects from MAS. Although the pathogenesis of MAS is unclear, the hallmark of the syndrome is an uncontrolled activation and proliferation of T lymphocytes and macrophages, leading to massive hypersecretion of proinflammatory cytokines. The first-line therapy of MAS complicating sJIA is based on the parenteral administration of high doses of corticosteroids, with or without cyclosporine. There is increasing evidence that biologic therapies, particularly IL-1 inhibitors, represent a valuable adjunct to corticosteroids and cyclosporine in treating MAS in the setting of sJIA.