Current approaches to diagnosing and treating macrophage activation syndrome in children with rheumatic diseases

Macrophage activation syndrome (MAS) is a severe life-threatening complication presenting with hemophagocytosis, pancytopenia, coagulopathy, and liver and CNS dysfunctions. The disease belongs to a group of histiocytic disorders. The common triggers for MAS are rheumatic diseases, particularly systemic juvenile idiopathic arthritis (SJIA), infectious diseases, immunodeficiency, and medication. The paper describes the main stages of the pathogenesis of MAS and the role of hypercytokinemia. It presents the clinical picture of MAS and hemophagocytic lymphohistiocytoses. The evolution of diagnostic approaches to diagnosing MAS and related conditions, such as hereditary and secondary hemophagocytic lymphohistiocytosis, is considered. It is shown that it is important to elaborate diagnostic criteria for patients with SJIA. Main current approaches to therapy for MAS are outlined.